CA1055005A - Single double backseat - Google Patents
Single double backseatInfo
- Publication number
- CA1055005A CA1055005A CA236,870A CA236870A CA1055005A CA 1055005 A CA1055005 A CA 1055005A CA 236870 A CA236870 A CA 236870A CA 1055005 A CA1055005 A CA 1055005A
- Authority
- CA
- Canada
- Prior art keywords
- metal
- seal ring
- closure
- open
- chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K41/00—Spindle sealings
- F16K41/02—Spindle sealings with stuffing-box ; Sealing rings
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
- F16K3/30—Details
- F16K3/36—Features relating to lubrication
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Sliding Valves (AREA)
- Lift Valve (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
HIGH PRESSURE VALVE
ABSTRACT
A valve comprising a housing with an inlet and out-let and a chamber in between, a reciprocating gate mounted in a gate seat disposed within the chamber for opening and closing the valve, an upper bonnet for closing the chamber at one end and a lower bonnet for closing the cham-ber at the other end, the gate being disposed between upper and lower stems which extend into the upper and lower bon-nets respectively. Metal-to-metal seals are provided at all junctures between the above members in the lower gate position with back-up seals at the junctures of all mov-ing members.
A double edged seal ring integral with the upper stem self-contained within the upper bonnet provides a metal-to-metal seal with the upper bonnet in the upper and lower gate positions of the valve.
A metal gasket arrangement is provided between the upper bonnet and valve body whereby the assemblage of all points of contact between the gasket and body form an annular ring.
A combination seal ring of metal and plastic is dis-posed between the gate seat and valve body at the outlet whereby the metal prevents the plastic from extruding be-tween the seat and body and into the outlet.
A removable backseat may be used to simultaneously seal the upper bonnet and upper stem upon moving the valve to one of its positions.
ABSTRACT
A valve comprising a housing with an inlet and out-let and a chamber in between, a reciprocating gate mounted in a gate seat disposed within the chamber for opening and closing the valve, an upper bonnet for closing the chamber at one end and a lower bonnet for closing the cham-ber at the other end, the gate being disposed between upper and lower stems which extend into the upper and lower bon-nets respectively. Metal-to-metal seals are provided at all junctures between the above members in the lower gate position with back-up seals at the junctures of all mov-ing members.
A double edged seal ring integral with the upper stem self-contained within the upper bonnet provides a metal-to-metal seal with the upper bonnet in the upper and lower gate positions of the valve.
A metal gasket arrangement is provided between the upper bonnet and valve body whereby the assemblage of all points of contact between the gasket and body form an annular ring.
A combination seal ring of metal and plastic is dis-posed between the gate seat and valve body at the outlet whereby the metal prevents the plastic from extruding be-tween the seat and body and into the outlet.
A removable backseat may be used to simultaneously seal the upper bonnet and upper stem upon moving the valve to one of its positions.
Description
lOS5005 This invention pertains to valves and especially to gate valves suitable for high pressure service. The invention is par~icularly directed to improvements in the seals and sealing arrangement for a through-conduit, rising stem high pressure gate valveO
Gate valves have been commonly used for many years and have been employed in a variety of services such as in the oil and/or gas services of the petroleum industryO However, such valves have been designed for service in-volving pressures of only several thousand pounds per square inch. Today dueto the depleted energy supply it has become necessary to explore and produce oil and gas under very high pressures of the range 30,000 psi (pounds per square inch) or more. Such high pressures have required greater sealing capacity and better safety features in such valves.
Prior art gate valves generally consist of a valve body having inlet and outlet conduits with a chamber therebetween. A gate having an opening therethrough is disposed in a gate seat mounted within the chamber and the gate is mounted on a stem. The chamber is closed by a bonnet affixed to the valve housing. The stem reciprocates within the bonnet and is attached to a reciprocating apparatus for moving the gate between a closed position in which flow is blocked through the conduits and an open position in which flow is allowed through the conduits and the gate opening. Such a valve is illustrated is U.S. Patent Nos. 3,538,938 issued November 10, 1970 to Volpin and 3,696,831 issued October 10, 1972 to Fowler.
A gasket seal is provided to seal between the bonnet and the valve housing. A ring gasket has been used as shown in UOS. Patent No. 2,433,638 issued December 30, 1947 to Volpin; 2,842,336 issued July 8, 1958 t,o Johnson;
and 3,696,831 referred to above or an o-ring seal as shown in U.S. Patent Nos.
3,095,004 issued June 25, 1963 to Jackson, Jr. et al, and 3,135,285 issued June 2, 1964 to Volpin. It is well known to use a standard metal joint gasket received in grooves at the flange faces of two wellhead members as shown in -' ,' U.S. Patcnt Nos. 2,830,665 issued April 15, 1958 to Burns et al and 3,007,719 issued November 7, 1961 to Sherman et al. Such gaskets may have a diamond shaped cross-section or a T-shaped cross-section as advertised by Gray Tool Company on pages 2217-2272 in the 1970-71 Composite Catalog of Oil Field Equipment and Services, 29th Revision, Volume 2, published by World Oil. A
resilient steel ring with o-rings for sealing between a valve housing and a bonnet of a gate valve is shown in U.S. Patent No. 2,780,233 issued February 5, 1957 to Volpin.
It is well known to seal between the gate seat and the valve housing by using an o-ring as shown in U.S. Patent Nos. 2,957,492 issued October 25, 1960 to Volpin and 3,348,567 issued October 24, 1967 to Volpin. Further in automatic pressure sealed gate valves shown in U.S. Patent Nos. 3,095,004 referred to above; 3,538,938 issued November 10, 1970 to Volpin; and 3,696,831 issued October 10, 1972 to Fowler, fluent sealant rings are disposed around the gate seats to provide sealing between the valve housing and gate seats in response to line pressure on fluent sealant reservoirs in communication with the fluent sealant rings, and o-rings are installed on each side of the fluent sealant rings to isolate the fluent sealant in the fluent sealant rings from contamination by line fluids. This same principle is used for seals in well-heads as shown in U.S. Patent No. 2,952,47Y issued September 13, 1960 to Rhodes et al. It is also known to locate an o-ring seal on the end of the gate seat as shown in U.S. Patent No. 3,696,831 referred to earlier. U.S. Patent Nos.
3,057,630 issued October 9, 1962 to Sneed and 3,758,072 issued September 11, 1973 to Herd teach combining an elastomeric O-ring and a polyfluoroethylene polymer such as the brand "Teflon" or "nylon" or other low-friction plastic ring to make a seal ring. "Teflon" is a trade mark for a high molecular weight polymer of tetrafluOroethylene. Further U.S. Patent No. 3,103,366 issued September 10, 1963 to Dunn teaches a deformable metal ring, as for example of aluminum, with an inner ~eformable plastic ring of polytetra-~.
` 1055005 fluoroct}lyletle whcrc~y thc metal ring can adapt itself to slightly varying recess clearances and prevent the plastic ring from extruding through the clearances under pressurc.
Generally the stem is sealed with the bonnet`by means of a seal such as an o-ring, compressed sealant, or shevron packing as are shown in UOS.
Patent Nos. 2,657,898 issued November 3, 1953 to Volpin; 2,780,233 issued February 5, 1957 to Volpin; 2,842,336 issued July 8, 1958 to Johnson;
Gate valves have been commonly used for many years and have been employed in a variety of services such as in the oil and/or gas services of the petroleum industryO However, such valves have been designed for service in-volving pressures of only several thousand pounds per square inch. Today dueto the depleted energy supply it has become necessary to explore and produce oil and gas under very high pressures of the range 30,000 psi (pounds per square inch) or more. Such high pressures have required greater sealing capacity and better safety features in such valves.
Prior art gate valves generally consist of a valve body having inlet and outlet conduits with a chamber therebetween. A gate having an opening therethrough is disposed in a gate seat mounted within the chamber and the gate is mounted on a stem. The chamber is closed by a bonnet affixed to the valve housing. The stem reciprocates within the bonnet and is attached to a reciprocating apparatus for moving the gate between a closed position in which flow is blocked through the conduits and an open position in which flow is allowed through the conduits and the gate opening. Such a valve is illustrated is U.S. Patent Nos. 3,538,938 issued November 10, 1970 to Volpin and 3,696,831 issued October 10, 1972 to Fowler.
A gasket seal is provided to seal between the bonnet and the valve housing. A ring gasket has been used as shown in UOS. Patent No. 2,433,638 issued December 30, 1947 to Volpin; 2,842,336 issued July 8, 1958 t,o Johnson;
and 3,696,831 referred to above or an o-ring seal as shown in U.S. Patent Nos.
3,095,004 issued June 25, 1963 to Jackson, Jr. et al, and 3,135,285 issued June 2, 1964 to Volpin. It is well known to use a standard metal joint gasket received in grooves at the flange faces of two wellhead members as shown in -' ,' U.S. Patcnt Nos. 2,830,665 issued April 15, 1958 to Burns et al and 3,007,719 issued November 7, 1961 to Sherman et al. Such gaskets may have a diamond shaped cross-section or a T-shaped cross-section as advertised by Gray Tool Company on pages 2217-2272 in the 1970-71 Composite Catalog of Oil Field Equipment and Services, 29th Revision, Volume 2, published by World Oil. A
resilient steel ring with o-rings for sealing between a valve housing and a bonnet of a gate valve is shown in U.S. Patent No. 2,780,233 issued February 5, 1957 to Volpin.
It is well known to seal between the gate seat and the valve housing by using an o-ring as shown in U.S. Patent Nos. 2,957,492 issued October 25, 1960 to Volpin and 3,348,567 issued October 24, 1967 to Volpin. Further in automatic pressure sealed gate valves shown in U.S. Patent Nos. 3,095,004 referred to above; 3,538,938 issued November 10, 1970 to Volpin; and 3,696,831 issued October 10, 1972 to Fowler, fluent sealant rings are disposed around the gate seats to provide sealing between the valve housing and gate seats in response to line pressure on fluent sealant reservoirs in communication with the fluent sealant rings, and o-rings are installed on each side of the fluent sealant rings to isolate the fluent sealant in the fluent sealant rings from contamination by line fluids. This same principle is used for seals in well-heads as shown in U.S. Patent No. 2,952,47Y issued September 13, 1960 to Rhodes et al. It is also known to locate an o-ring seal on the end of the gate seat as shown in U.S. Patent No. 3,696,831 referred to earlier. U.S. Patent Nos.
3,057,630 issued October 9, 1962 to Sneed and 3,758,072 issued September 11, 1973 to Herd teach combining an elastomeric O-ring and a polyfluoroethylene polymer such as the brand "Teflon" or "nylon" or other low-friction plastic ring to make a seal ring. "Teflon" is a trade mark for a high molecular weight polymer of tetrafluOroethylene. Further U.S. Patent No. 3,103,366 issued September 10, 1963 to Dunn teaches a deformable metal ring, as for example of aluminum, with an inner ~eformable plastic ring of polytetra-~.
` 1055005 fluoroct}lyletle whcrc~y thc metal ring can adapt itself to slightly varying recess clearances and prevent the plastic ring from extruding through the clearances under pressurc.
Generally the stem is sealed with the bonnet`by means of a seal such as an o-ring, compressed sealant, or shevron packing as are shown in UOS.
Patent Nos. 2,657,898 issued November 3, 1953 to Volpin; 2,780,233 issued February 5, 1957 to Volpin; 2,842,336 issued July 8, 1958 to Johnson;
2,957,492 issued October 25, 1960 to Volpin; 3,095,004 issued June 25, 1963 to Jackson, Jr. et al; 3,181,552 issued May 4, 1965 to Jackson, Jr. and 3,696,831 issued October 10, 1972 to FowlerO Various valves such as are disclosed in U.S. Patent Nos. 2,657,721; 2,780,233; 2,842,336; and 3,348,567 all referred to previously show back seats which are actuated to provide a metal-to-metal seal between the stem and the bonnet and/or valve housing when it is necessary to replace the packing around the stem. U.S. Patent No. 3,013,769 issued December 10, 1961 to Volpin discloses two separate seat rings mounted on the stem one of which will sealingly engage the bonnet either in the open position or in the closed position of the valve. UOS. Patent No. 3,538,938 refcrred to earlier illustrates upper and lower stem sections with annular packing between the upper stem section and bonnet and between the lower stem section and valve housing, and fur-.. ~ ~ , 10550(~5 ther discloses upper and lower enlargements mounted on the upper and lowerstem sections respectively.
The sealing systems and arrangements of the prior art gate valves were designed for working pressures in the range of several thousand pounds psi and are not able to service working pressures in the range of 30,000 psi.
The prior art valves do not provide back-up seals if the stem seals blow out under high pressure and the stem seals are elastomeric seals and not metal-to-metal seals. Such sealing systems may permit the leakage of poisonous hydrogen sulfide gas under high pressure. Further gate seat seals will extrude and roll out of the seal grooves under high pressures.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a valve comprising: a valve body having an inlet and an outlet with a chamber therebetween; closure means for preventing flow in the closed position and permitting flow in the open position; moving means for moving said closure means between the open and closed positions; first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members; and ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions; and single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions.
According to another aspect of the invention there is provided a sealing system for valve members of a high pressure valve including a valve body having upstream and downstream conduits, a bonnet mounted on the body, an upper stem and a lower stem mounted within the valve body and bonnet and having a gate disposed therebetween, a gate seat disposed within the body for housing the gate, and the valve having a normal position for the gate, the improvement comprising: metal-to-metal seals in the normal position between the bonnet and upper stem and the lower stem and body.
According to a further aspect of the invention there is provided _~_ 1alS50t~5 a high pressure valve including a valve body having inlet and outlet conduits and an upper aperture with a chamber therebetween and a bonnet covering the upper aperture, an upper stem and a lower stem mounted within the valve body and having a gate disposed therebetween, a gate seat disposed within the chamber and housing the gate, an open position where the gate permits flow through the conduits and a closed position where the gate blocks flow through the conduits, and moving means for moving the gate between the open and closed positions, the improvement comprising: first seal means disposed on the upper stem for sealing engagement with the valve body bonnet upon movement of the gate into one of the positions by the moving means; and second seal means disposed on the lower stem for sealing engagement with the valve body upon line pressure activation, said second seal means including means for permitting said second seal means to be actuated prior to the sealing engagement of said first seal means.
The invention also provides a valve, comprising: a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween; closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber; moving means for moving said closure means between the open and closed positions; seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions.
In another aspect the invention provides in a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber therebetween, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through sa-d upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
- 5a -D
1055(~05 closing means on said stems movable, upon movement of said closure member toone of said open and closed positions, to a position closing both of said upper and lower apertures; said closing means on said stems including a metal seal member on each of the upper and lower stems; and a metal seat surround-ing each of the upper and lower apertures, each engageable by one of said seal members.
The inventivn also provides in a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid f~ow is permitted between saidinlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap cover-ing the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises: closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower aper-tures; and at least one of the closing means including holding means responsive to line pressure for maintaining said closing means in said position closing said lower aperture.
~ 50 ~ 5 The present application is one of three related applications in one of which the entire sealing system and arrangement are claimed, in another the sealing assembly is claimed, and in another the double edged backseat is claimed.
Other objects and advanta9e5 of the invention will appear from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed description of a preferred embodiment of the invention, reference will now be made to the accompanying drawings wherein: : .
Figure 1 is an elevation view in section of a valve accord-ing to a preferred embodiment of the invention showing the valve in the closed position;
. Figure 2 is an enlargement of the upper and lower portions of the view of the valve shown in Figure l;
Figure 3 is an enlargement of a portion of one of the gate--sea~-s--and-va~e housi~g---showni n-Figure l;
Figure 4A is an axial section view of the gate seat seal : shown in Figure 3 prior tD installation of the gate seat in the valve housing as shown in Figure 3;
Figure 4B is an axial section view of the gate seat seal shown in Figure 3 after installation of the gate seat in the valve housing as shown in Figure 3;
Figure 5A is an axial section view of the initial mating 25 of the bonnet gasket between the bonnet and valve housing ill- -ustrated in Figure l;
Figure 5B is an axial section view of the bonnet gasket installed in the bonnet and ready for installation llD55~05 1 in the valve housing;
Figure 6A is an axial section view of an alterna~
tive embodiment of the gate seat seal prior to installa-tion in the valvc housing;
Figure 6B is an axial section view of the embodi-ment of the gate seat seal shown in Figure 6A installed in the valve housing; and Figure 7 is an axial section view of an alternative embodiment illustrating a removable backseat disposed on the upper stem.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The valve~ in accordance with the preferred embodi-ment illustrated in Figures 1-5, inclusive, is of the through-conduit, rising stem, gate type, comprising a valve housing or body 10 having opposed flow ports 12, 14 either of which may be the inlet or outlet depending upon the orientation of the valve in the line in which the valve is mounted, forming the flowway 16 which is inter-sected interiorly of the housing 10 by a cylindrical clo-sure or gate chamber 18 whose axis is generally at right angles to the flow way. As illustrated, flow port 14 is the upstream portion or inlet of the valve and flow port 12 is the downstream or outlet of the valve. The fluent material flowing through the line and valve shall be termed line fluids. The inner ends of flow ports 14, 12 are provided with coaxial counterbores 20, 22 respectively, circum-scribing flow ports 12, 14 and forming inwardly facing annular shoulders 24, 26 and inwardly facing cylindrical walls 28, 30 respectively, the counterbore walls 28, 30 having a larger diameter than the diameter o~ flow ports 12, 14.
Closure chamber 18 and counterbores 20, 22 are adapted ~ O S 50 ~ 5 to receive a pair of gate seat members 32, 34 respectively.
As gate seat members 32 9 34 and their appurtenances are identical in construction and are arranged symetrically on opposite sides of closure chamber 18, the description of one will, it will be understood, be applicable to both.
The gate seat member 34 is elongate in form, having an inwar~ly facing surface shaped to cooperate in slid-ing engagement with the abutting face of gate 40, as will be described hereinafter, and an outwardly facing surface 42 shaped to be substantially complimentary to the shape of the portion of the wall 44 forming closure chamber 18 surrounding the flowports 12, 14 and extending longitudi-nally of the chamber 18. In the illustrative embodiment where gate 40 is of the flat-sided form, inner surface:
46 will likewise be flat. Fur.ther, gate seat member 34 includes a seat neck or hub 50 to be received by counter-bore 22. Gate seat r.ember 34 is provided with a trans-verse opening 52 coaxial and registering with flow port 12 and flowway 16 and generally of the same diameter to provide full open flow therethrough.
The upper end portion cf gate seat member 34 is bored from its outer end to provide a reservoir 54~ adapted for receiving a flowable or fluent sealant 56, such as is con-ventionally used in automatically sealing valves. A cylin-drical piston or barrier 57 is slidably mounted in reser-voir 54 for pressurizing the sealant as will be subsequently described. Referring now to Figure 3 the lower end of reservoir 54 communlcates through a longitudinal passage 58 with a passage 60 which extends transversely through the body of the gate seat member 34 tD the outer peripheral surface 62 of seat hub 50. The outer end of transverse :lOSS(~05 passage 60 communicates with an annular sealant groove 64 formed in outer surface 62 of gate seat member 34 en-circling opening 52. The lower end of reservoir 54 also communicates through a transverse passage'66 which com-municates with the exterior of inner face 46 of gate seat member 34 and is spaced from an annular sealing groove 68 formed in inner surface 46 encircling opening 52.
Referring to Figure 3 a threaded socket 234, shown generally. is formed in the side of body 10 and i~ adapted to receive a conventional pressure fitting for introduc-ing sealant material 56 into socket 234. With this ar-rangement. it will be seen that sealant 56 introduced through - the fitting will be forced via passage 236 through groove 64, thence via passage 60 and 58 into the interior of re-servoir 54 below barrier 57~
~e~-e~ing--ag~ n-*o~ ur~ ga~e-40i s~ sposed-in -closure chamber 18 for vertical reciprocation across the O, flowwaY 16 between the gate seats 32, 34. The gate 40 is constructed of a pair of mating generally rectangular gate segments, 70, 72 having flat outer faces adapted for slidable engagement with the inner end faces 45, 46 of the seat members 32, 34. The gate 40 is provided near its-lower end with a transverse flow port 74, defined by registered openings in ~ate segments 70, 72, and adapted 2~ to register with openings ~2, 53 in seat members 32, 34 when the gate 40 is in the raised or flowway-opening posi-tion. The upper portions of the gate segments 70, 72 form the closure section 76 which is adapted to cut off flow through flowway 16 when the gate is in the lower or flow- -way-closing posit~on as seen in Figures 1, 2, and 3. The upper portion of gate segment 72 is provided on its outer l oss oo s face with a jumper recess 78 shown in Figure 3 adapted - to communicate sealant groove 68 with the inner end of transverse passage 66 when gate 40 and gate segment 72 are in the flowway-closing position as shown in Figure
The sealing systems and arrangements of the prior art gate valves were designed for working pressures in the range of several thousand pounds psi and are not able to service working pressures in the range of 30,000 psi.
The prior art valves do not provide back-up seals if the stem seals blow out under high pressure and the stem seals are elastomeric seals and not metal-to-metal seals. Such sealing systems may permit the leakage of poisonous hydrogen sulfide gas under high pressure. Further gate seat seals will extrude and roll out of the seal grooves under high pressures.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a valve comprising: a valve body having an inlet and an outlet with a chamber therebetween; closure means for preventing flow in the closed position and permitting flow in the open position; moving means for moving said closure means between the open and closed positions; first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members; and ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions; and single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions.
According to another aspect of the invention there is provided a sealing system for valve members of a high pressure valve including a valve body having upstream and downstream conduits, a bonnet mounted on the body, an upper stem and a lower stem mounted within the valve body and bonnet and having a gate disposed therebetween, a gate seat disposed within the body for housing the gate, and the valve having a normal position for the gate, the improvement comprising: metal-to-metal seals in the normal position between the bonnet and upper stem and the lower stem and body.
According to a further aspect of the invention there is provided _~_ 1alS50t~5 a high pressure valve including a valve body having inlet and outlet conduits and an upper aperture with a chamber therebetween and a bonnet covering the upper aperture, an upper stem and a lower stem mounted within the valve body and having a gate disposed therebetween, a gate seat disposed within the chamber and housing the gate, an open position where the gate permits flow through the conduits and a closed position where the gate blocks flow through the conduits, and moving means for moving the gate between the open and closed positions, the improvement comprising: first seal means disposed on the upper stem for sealing engagement with the valve body bonnet upon movement of the gate into one of the positions by the moving means; and second seal means disposed on the lower stem for sealing engagement with the valve body upon line pressure activation, said second seal means including means for permitting said second seal means to be actuated prior to the sealing engagement of said first seal means.
The invention also provides a valve, comprising: a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween; closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber; moving means for moving said closure means between the open and closed positions; seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions.
In another aspect the invention provides in a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber therebetween, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through sa-d upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
- 5a -D
1055(~05 closing means on said stems movable, upon movement of said closure member toone of said open and closed positions, to a position closing both of said upper and lower apertures; said closing means on said stems including a metal seal member on each of the upper and lower stems; and a metal seat surround-ing each of the upper and lower apertures, each engageable by one of said seal members.
The inventivn also provides in a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid f~ow is permitted between saidinlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap cover-ing the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises: closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower aper-tures; and at least one of the closing means including holding means responsive to line pressure for maintaining said closing means in said position closing said lower aperture.
~ 50 ~ 5 The present application is one of three related applications in one of which the entire sealing system and arrangement are claimed, in another the sealing assembly is claimed, and in another the double edged backseat is claimed.
Other objects and advanta9e5 of the invention will appear from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed description of a preferred embodiment of the invention, reference will now be made to the accompanying drawings wherein: : .
Figure 1 is an elevation view in section of a valve accord-ing to a preferred embodiment of the invention showing the valve in the closed position;
. Figure 2 is an enlargement of the upper and lower portions of the view of the valve shown in Figure l;
Figure 3 is an enlargement of a portion of one of the gate--sea~-s--and-va~e housi~g---showni n-Figure l;
Figure 4A is an axial section view of the gate seat seal : shown in Figure 3 prior tD installation of the gate seat in the valve housing as shown in Figure 3;
Figure 4B is an axial section view of the gate seat seal shown in Figure 3 after installation of the gate seat in the valve housing as shown in Figure 3;
Figure 5A is an axial section view of the initial mating 25 of the bonnet gasket between the bonnet and valve housing ill- -ustrated in Figure l;
Figure 5B is an axial section view of the bonnet gasket installed in the bonnet and ready for installation llD55~05 1 in the valve housing;
Figure 6A is an axial section view of an alterna~
tive embodiment of the gate seat seal prior to installa-tion in the valvc housing;
Figure 6B is an axial section view of the embodi-ment of the gate seat seal shown in Figure 6A installed in the valve housing; and Figure 7 is an axial section view of an alternative embodiment illustrating a removable backseat disposed on the upper stem.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The valve~ in accordance with the preferred embodi-ment illustrated in Figures 1-5, inclusive, is of the through-conduit, rising stem, gate type, comprising a valve housing or body 10 having opposed flow ports 12, 14 either of which may be the inlet or outlet depending upon the orientation of the valve in the line in which the valve is mounted, forming the flowway 16 which is inter-sected interiorly of the housing 10 by a cylindrical clo-sure or gate chamber 18 whose axis is generally at right angles to the flow way. As illustrated, flow port 14 is the upstream portion or inlet of the valve and flow port 12 is the downstream or outlet of the valve. The fluent material flowing through the line and valve shall be termed line fluids. The inner ends of flow ports 14, 12 are provided with coaxial counterbores 20, 22 respectively, circum-scribing flow ports 12, 14 and forming inwardly facing annular shoulders 24, 26 and inwardly facing cylindrical walls 28, 30 respectively, the counterbore walls 28, 30 having a larger diameter than the diameter o~ flow ports 12, 14.
Closure chamber 18 and counterbores 20, 22 are adapted ~ O S 50 ~ 5 to receive a pair of gate seat members 32, 34 respectively.
As gate seat members 32 9 34 and their appurtenances are identical in construction and are arranged symetrically on opposite sides of closure chamber 18, the description of one will, it will be understood, be applicable to both.
The gate seat member 34 is elongate in form, having an inwar~ly facing surface shaped to cooperate in slid-ing engagement with the abutting face of gate 40, as will be described hereinafter, and an outwardly facing surface 42 shaped to be substantially complimentary to the shape of the portion of the wall 44 forming closure chamber 18 surrounding the flowports 12, 14 and extending longitudi-nally of the chamber 18. In the illustrative embodiment where gate 40 is of the flat-sided form, inner surface:
46 will likewise be flat. Fur.ther, gate seat member 34 includes a seat neck or hub 50 to be received by counter-bore 22. Gate seat r.ember 34 is provided with a trans-verse opening 52 coaxial and registering with flow port 12 and flowway 16 and generally of the same diameter to provide full open flow therethrough.
The upper end portion cf gate seat member 34 is bored from its outer end to provide a reservoir 54~ adapted for receiving a flowable or fluent sealant 56, such as is con-ventionally used in automatically sealing valves. A cylin-drical piston or barrier 57 is slidably mounted in reser-voir 54 for pressurizing the sealant as will be subsequently described. Referring now to Figure 3 the lower end of reservoir 54 communlcates through a longitudinal passage 58 with a passage 60 which extends transversely through the body of the gate seat member 34 tD the outer peripheral surface 62 of seat hub 50. The outer end of transverse :lOSS(~05 passage 60 communicates with an annular sealant groove 64 formed in outer surface 62 of gate seat member 34 en-circling opening 52. The lower end of reservoir 54 also communicates through a transverse passage'66 which com-municates with the exterior of inner face 46 of gate seat member 34 and is spaced from an annular sealing groove 68 formed in inner surface 46 encircling opening 52.
Referring to Figure 3 a threaded socket 234, shown generally. is formed in the side of body 10 and i~ adapted to receive a conventional pressure fitting for introduc-ing sealant material 56 into socket 234. With this ar-rangement. it will be seen that sealant 56 introduced through - the fitting will be forced via passage 236 through groove 64, thence via passage 60 and 58 into the interior of re-servoir 54 below barrier 57~
~e~-e~ing--ag~ n-*o~ ur~ ga~e-40i s~ sposed-in -closure chamber 18 for vertical reciprocation across the O, flowwaY 16 between the gate seats 32, 34. The gate 40 is constructed of a pair of mating generally rectangular gate segments, 70, 72 having flat outer faces adapted for slidable engagement with the inner end faces 45, 46 of the seat members 32, 34. The gate 40 is provided near its-lower end with a transverse flow port 74, defined by registered openings in ~ate segments 70, 72, and adapted 2~ to register with openings ~2, 53 in seat members 32, 34 when the gate 40 is in the raised or flowway-opening posi-tion. The upper portions of the gate segments 70, 72 form the closure section 76 which is adapted to cut off flow through flowway 16 when the gate is in the lower or flow- -way-closing posit~on as seen in Figures 1, 2, and 3. The upper portion of gate segment 72 is provided on its outer l oss oo s face with a jumper recess 78 shown in Figure 3 adapted - to communicate sealant groove 68 with the inner end of transverse passage 66 when gate 40 and gate segment 72 are in the flowway-closing position as shown in Figure
3. It will be understood that when the gate 40 is moved upwardly to the flowway-opening position, the correspond-ing displacement of recess 7~ will serve to disconnect groove 68 from passage 66.
It should be understood that the valve shown in the figures is normal acting in that during service of the valve it is anticipated that the valve will generally be closed to fluid flow. However the valve could obviously be reverse acting whereby during service the valve would generally be in the open position. ~he normal acting valve 1~ shown can be made reverse acting by merely modifying gate segments 70, 72 whereby transverse flow port 74 will register ~i~h openings 52, 53 when the gate is in the lower position rather than in the upper position as previously described.
Note that regardless of whether ~he valve is normal acting or reverse acting, the normal position (i.e. the general position of the valve during operation) will occur when the gate 40 is in the lower position.
Referring now to Figures 3, 4A and 4B, seals 230,-240 are received in annular grooves 232, 242 which cir-cumscribe seat hub 50 for sealing with surface 30 of hous-ing 10 on opposite sides of the sealant groove 64. Seal 230 is an elastomeric or plastic o-ring seal while seal 240 is an integral plastic-metal seal ring. Seal 240 in-p ~ f7 4/~ 0 ro e ~/e~7c cludes an annular metal ring 244 and a~e~fuer~e~ e~
or polymer such as the brand "Teflon",~"nylon"~ or other low-friction plastic annular ring 246. Groove 242 is located 1055005 , ~_ at the outer peripheral corner of hub 50 whereby groove 242 is two-sided with the opposing surfaces of counter-bore 22 providing the other two sides. Ideally the thick-ness of seal 240 will be equal to the length of the groove 242 with the tolerance being on the side of seal 240 hav-ing a greater thickness. Preferably the volume of groove 242 will substantially equal the volume of seal 240. The metal ring 244 has a close fit around groove 242 and is preferably press ~itted onto groove 242. Upon assembly as shown in Figures 1 and 4B gate seat members 32, 34 are inserted into closure member 18 whereby opposing seat hubs 50, 51 are inserted into corresponding counterbores 20 . 22 respectively. The leading edges 21, 23 at the entrances of counterbores 20, 22 respectively are beveled to facili-tate the assembly of hubs S0, 51. Upon assembly the metal ring 244 engages the bottom of groove 242 and shoulder 26 of counterbore 22 with plastic ring 24~ sub~tantially filling the remainder of groove 242.
The surfaces between shoulder 26 of counterbore 22 and the end face 243 of hub 50 cannot be matingly machined to effect a proper seal thereby requiring seal 240. How-ever, such machining may be accomplished for a proper metal-to-metal sealing engagement between the outer wall 73 of gate segment 72 and the inner surface 46 o~ gate seat mem-ber 34. Further it should be noted that to effect an ade-quate seal w~th seal 240, the area of the radially extend-ing annular wall 243 of groove 242 facing towards shoulder 26 of counterbore 22 must be less than the area of gate segment 72 encircled by sealant groove 68 exposed to line pressure through port 12. If the pressure on wall 243 due to sealant 56 is greater than the pressure on gate seg-~.055005 - /~3~
ment 72 due to line pressure, wall 243 will tend to move , - away from shoulder 26 thereby disengaging seal 240.
Referring now to Figures 1 an~ 2 gate 4D is recipro~
cated by means of a pressure balanced stem having an upper stem member 80 an,d a lower stem member 82. Lower stem member 82 includes a head 84 at its upper end which is enclosed between gate segments 70, 72 within counterbores 86, 88 in the inner faces of the lower portions of seg-ments 70, 72. Counterbores 86, 88 have sufficient axial length to permit l;mited axial movement of head 84 with respect to gate 40. Upper stem member 80 includes a T-shaped lug member 90,threaded or welded onto the lower end of upper stem member 80. The T-shaped lug member 90 is also enclosed between gate segments 70, 72 within cor-responding T-shaped and semi-circular counterbores 92, 94. This structure is old and forms no part of the present invention, therefore a more detailed description has not been made.
The lower end of the valve housing 10 is provided with a bore 95 coaxial with chamber 18 and with a coun-terbore 96 opening from the outer end of housing 10 form-ing a stuffing box for receiving lower stem member 82 and adapted to receive an annular packing 98 under compres-sion by a compression ring 100 and a gland 102 protrud-2~ ing from a lower closure cap 104 secured to the housing 10 by cap screws 106 or possibly by bolts. The housing 10 and closure cap 104 have corresponding mating annular grooves 108. 110 for receiving a lower ring gasket 112 to provide a metal-to-metal seal therebetween. The lower closure cap 104 has a bore 114 for slidingly receiving the lower stem member 82. A transverse pass~ge 116 in 1055~05 ~4 closure cap 104 provides communication between bore 114 and bleeder valve 118 to relieve any build up of line fluids in bore 114. The lower stem member 82 reciprocates in response to reciprocal movement of the gate 40, and pack-ing 98 serves to slidably seal about the lower stem mem-ber 82.
There is provided on the upper portion of lower stem member 82 below head 84 a metal seat ring 120 definlng a downwardly facing annular shoulder 122 surrounding the lower end of seat ring 120. Shoulder 122 is arcuate and cooperates with a bevelled seat 124 located at the entrance of bore 95 at the bottom of chamber 18 forming a line contact and a metal-to-metal seal therewith as will be described subsequently.
Referring to Figure 2 the upper end 128 of chamber 18 is adapted to be closed by means of a ~ub~ r-ca~-or bonnet 130 having a closure f~ange 132 secured to the upper end 134 of housing 10 by means of studs 136 or possibly by bolts or capscrews. Bonnet 130 has an axial bore 13B for receiving upper stem member 80. Upper stem member 80 has a double seal or backseat 220 radially projecting from and integral (i.e. the backseat 220 and stem 80 are one piece) with upper stem 80 thereby preventing any leakage behind the backseat 220. Backseat 220 has upwardly fac-ing and downwardly facing rounded shoulders 222, 224 and stress relief grooves 226, 228 adjacent thereto on each side of backseat 220. Shoulders 222, 224 are pl aced ap-proximately back to back to limit the longitudinal dimen-sion of bonnet 130.
Axial bore 138 includes an enlarged portion 154 hav-ing a diameter greater than the diameter of backseat 220 1LO55005 - ~ ~
for receiving same- Enlarged portion 154 terminates in a lower counterbore 15~ which is adapted to receive clo-sure ring 160 having an axîal stem - receiving bore 184 coaxial with closure cham~er 18 and bonnet bore 138. In the assembly of the valve upper stem member 80 is inserted into bore 138 with enlarged portion 154 receiving back-seat 220. Closure ring 160 then slides around upper stem member 80 behind backseat 220 and is rece;ved by counter-bore 158. It is at this time that lug member 90 is threaded onto upper stem member 80 for attachment with gate 40 and gate 40 is inserted between gate seat members 32, 34.
Closure ring 160 when received within counterbore 158 makes enlarged portion 154 into a chamber for the re-ciprocation of backseat 220. Enlarged portion 154 forms an internal downwardly facing beveled shoulder or seat 156 and ring 160 includes an upwardly facing beveled coni-~
cal shoulder or seat 186 at the upper end of bore 184 op-posing shoulder 156 after assembly.
Backseat 220 and seat ring 120 are formed in spaced-apart relation on upper stem 80 and on lower stem 82 re-spectively whereby in the closed flowway position, back-seat 220 will sealingly engage shoulder 186 providing a metal-to-metal seal therebetween and seat ring 120 will sealingly engage shoulder 124 providing a seal therebe-2', tween as the line fluid pressure forces seat ring 120 down-wardly by means of the limited axial movement of head 84 within counterbores 86, 88. Backseat 220 is also spaced on upper stem 80 whereby in the open flowway position seat 220 will sealingly engage shoulder 156 providing a metal-to-metal seal therebetween.
The closure ring 160 and its appurtenances are iden-1055005 ~
tical in construction and are arranged symmetrically on both upper and lower sides to permit reversability, so the description of one will be applicable to both. Ring 160 includes an upper and lower ring gasket groove 162, 164 for receiving upper and lower metal ring gaskets 166, 168 for sealing between the bonnet 130 and ring 160 and ring 160 and housing 10. Ring gasket groove 164 includes a downwardly and inwardly facing frusto-conical seat or shoulder 188, a downwardly facing inner annular shoulder 190, a downwardly and outwardly facing beveled conical shoulder 192, and a downwardly facing outer annular shoul-der 194. Shoulders 188, 190, 192 and 194 having decreas-- ing diameters respectively. The bottom portion of coun-terbore 158 includes a ring gasket groove 196-having the 1~ same features and dimensions as groove 164. Further ring gasket grooves 108, 110 in lower housing 10 and cap 104 have the sa~e features, dimensions and arrangements as grooves 196, 162. At the mouth of closure chamber 18 there is an inwardly extending annular boss 198 bounded by upper zo and lower frusto-conical shoulders or seats 200, 202. Shoul-der 200 mates and opposes shoulder 188 on closure ring 160. However, there is no corresponding upwardly facing annular shoulder on boss 198 opposing shoulder 194 on clo-sure ring 160.
Ring gaskets 112, 166 and 168 are identical in dimen-sion for interchangeability and therefore a description of one will apply to all.
Referring now to Figures 5A and 5B, ring gasket 168 is an annular ring having a T-shaped cross section. The stem 169 of the T-shaped cross section lies in a horizon-tal plane perpendicular to the axis of the bore 173 of the gasket 168 and the head 171 of the T-shaped cross section lies in a vertical plane parallel to the axis of the bore 173 The outer,peripheral annular edges 204, 206 of the head 171 are beveled for engagement wit~, annular seats or shoulders 188, 200 respectively. Gasket 168 is made of metal, prefer-ably steel.
Figure 5A illustrates the initial assembly position of gasket 168, before the gasket is compressed. The dimension X between closure ring 160 and housing 10 is approximately twice the dimension Y between stem 169 and shoulder 194 whereby as studs 136 are tightened, bonnet 130 and closure ring 160 will move downwardly the distance Y until annular sho,ulder 194 contacts the upwardly facing surface of stem 169 of gasket 168. This position is illustrated in Figure 5B at which time the dimension'Z between closure ring 160 and housing 10 is approximately one-half the dimension X. Upon tightening studs 136, gasket 168 is engaged-at points 208, 210 by closure ring 160 and is forced against shoulder 200 until the connection is complete as shown in Figure 1 and 2. As shown in Figure 2, gasket 168 has surface-to-surface contact at 211 with shoulder 200 of housing 10. Upon completion of the assembly gasket 168 engages closure ring 160 at points, the assemblage or loci of which, forms two annular rings, and gasket 168 engages housing 10 at points, the assemblage or locus of which, forms a single annular ring. During the assembly beveled edges 204, 206 are deformed against shoulders 188, 200 thereby establishing a high pressure metal-to-metal seal. Such deformation occurs because the median diameters of corners 204, 206 are slightly larger than the median diameters of shoulders 18B, 200.
1~ _ ~L055~)05 Standard metal ring gasket seals, as illustrated in Figures 5A and 5B at 212, which is slightly different than that shown in Figure 1, may be used in grooves 162, 196, and 1~8, 110 since the ring grooves are symmetrical with opposing surfaces. However, such gaskets cannot be used between bonnet 130 an:d housing 10 because there is no upwardly facing annular shoulder on boss 198 corresponding to shoulder 194 on ring 160 as previously shown.
rhe lack of this shoulder causes a standard gasket ring to be unstable, to rock under load and to misalign on shoulder 200 during assembly thereby providing a bad seal. If gasket 168 attempts to cock,-stem 169 engages shoulder 208 which forces gasket 168 back into alignment. To place a shoulder on boss 198 would require a larger housing 10 and a larger bonnet 130 to provide clearance for the installation and removal of ga~te 40 and gate seat members 32, 34.
Referring now to Figure 1, upper stem member 80 is provided' with an externally threaded portion 170 at its upper end which extends through stuffing box 142 wherein packing 144 se,rves ~to slidably seal about the stem member 80. An internally threaded drive nut 172 extends into cap 152 and is internally threaded at 174 to threadingly engage threaded portion 170 whereby rotation of the nut 172 wlll serve to raise and lower the closure member, i.e. stem members 80, 82 and gate 40, in ~ accordance with the direction of the rotation of the nut 172, in order to move the gate 40 between flowway-opening and flow-way-closing positions. The lower end of the nut 172 has an annular flange 173 which supports upper antifricition bearings 176 against the top of eap 152 and bears against lower anti-friction bearings 178 which rest on gland 150. The up-~05S005 per portion of the nut 172 which projects above the cap152, is provided with conventional flats at 180 for mount-ing an operating wheel 182 or other conventional operator, by which the gate 40 is actuated.
A bleeder valve 223 communicating with bore 138 by means of passage 225 through bonnet 130 provides a means to relieve bore 138 of any build up of line fluids when packing 144 is to be replaced.
The metal-to-metal seals at 156, 222;186, 224; and 120, 124 isolate packing 144 and 98 from long exposure to line fluids thereby preserving packing 98, 144 from deterioration.
Further the packing 98, 144 and such metal-to-metal seals provide dual sealing as a safety feature so if one seal blows or ruptures, there is a back up seal. Such metal-to-metal seals also provide the capability to remove and replace packings 98, 144 while the valve is under pressure although packings 98 and 144 are designed to operate throughout the life of the valve.
In operation as the valve is closed by operator 182, upper stem 80, gate 40, and lower stem 82 move downwardly into the lower position. Seat 120 on lower stem 82 seals with shoulder 124. Seat 120 is not mechanically actuated into sealing engagement but the line pressure forces seat 120 into sealing engagement with shoulder 124. Such move-ment by seat 120 is allowed by the limited axial movement permitted between head 84 and gate 40 which may be consid-ered a lost motion connection. Backseat 220 then engages shoulder 186 forming a metal-to-metal seal. After seat 120 engages shoulder 124, futher movement downwardly by upper stem 80 drives backseat 220 onto shoulder 186. As the valve is opened by operator 182, backseat 220 travels upwardly until backseat 220 sealingly engages 1055~S ~ ~ c -1 shoulder 156 providing a metal-to-:netal seal.
In closing or opening the valve5 bleeder valve 118 should be open whereby the line pressure will prov;de a ; balanced pressure force on both the lower stem 82 and up-per stem 80. Without such a balanced pressurized stem, the pressure on the upper stem 80 would place such a load on stem 80 as to require a very high torque to be used on stem 80 to open and close the Yalve. Bleeder valve 118 is used to bleed out pressure below lower stem 82 so as to prevent any upward pressure on stem 82.
It will be seen that when the gate 40 is moved to the flowway-closing position, shown in Figure 1, the dif-ferential line pressure across the closed valve will act on the downstream reservoir 54, the differential line pres-sure being exerted against the barrier 57 urging it in-wardly of reservoir 54 and simultaneously forcing seal-ant 56 from reservoir 54 into sealant groove 64 to seal off between outer surface 62 of the hub 50 and the sur-rounding wall 30 of chamber 18, and through passage 66 and recess 78 into sealant groove 68 provided at the inner surface of the seat member 72 to seal about the opening between the seat member 34 and the related closure seg-ment 72. Thus, sealant seals will automatically be pro-vided between both surfaces 46, 62 of the seat member 34 and the related portions of the closure segment 72 and the wall 30 of chamber 1~. The sealing action will be simultaneous.
Seals 230, 240 will be effective to prevent loss of sealant 56 from sealant groove 64. This permits effective sealing of the exterior of seat hub 50 while assuring against loss of sealant 56 due to any gap between the hub 50 and loss ~os body 10 at counterbore 22.
As line pressure reaches 30,000 psi, the yield strength of ordinary sealing materials is approached under confined streSs- Even below yield stress" there is substantial movement so that ordinary o-rings will not hold. The differ-ential pressure between chamber 18 and sealant groove 64 is very low but the differential pressure between groove 64 and port 14 is very high placing much pressure on seal 240. However, as high pressure is placed on plastic ring 246, metal ring ~44 is forced into the corner of groove 242 closing any gap or clearance a* the downstream juncture of the hub 50 and housing 10 and preventing the plastic ring 246 from extruding through any downstrearn clearance between the end face 243 of hub 50 and shoulder 26. The metal ring 244 can adapt itself to varying clearances be-tween the hub 50 and ~ousing 10 so that t~lese are not criti-Ocal. Thus the high press~ure.helps the seal.
Figures 6A and 6B illustrate an alternative sealing system for sealant groove 64 by sealing between surface 62 of hub 50 and wall 30 of counterbore 22. As shown in the unassembled position in Figure 6A, a plastic seal ring 300 is received in annular groove 302 in hub 50 interiorly of sealant grooYe 64. On the outer end portion of hub 50 is a reduced diameter portion 304 having an annular channel 306 on the outer end of portion 304. A plastic seal ring 308 is slipped over the portion 304 against annu-lar shoulder 310 formed by the reduction in diameter of portion 304. Two annular wedge or cam rings 312, 314 hav-i-ng Opposing upwardly and downwardly facing bevel 5 are slipped o~er portion 304. Then a split backup ring 316 hav~ng two semi-circular serttons and an inwardly extend-ing annular projection 318 is installed by inserting annu-lar projection 318 into channel 306. Projection 318 has a shorter length than the depth of channel 306. For as-sembly purposes the outer peripheral corner of backup ring 316 is chamfered for ease of insertion of hub 50 by contacting bevel 23 of housing 10. Further bevel 23 ~orces plastic rings 300, 308 into co~pressiQn within grooves 302 and portion 304.
; Upon expansion of the annular channel formed between reduced portion 304 and wall 30 due to line pressure, as shown in Figure 6B, wedge ring 312 will tend to cam onto wedge ring 314 creating a metal-to-metal sealing engage-ment ~etween portion 304 and ~all 30. Further such seal-ing engagement will prevent the extrusion of plastic seal ring 308 as shown in Figure 6B. Such camming or wedging o~-ring~-~12~ 14-~ccu~s-f-rom-the-rad-ial-sup~rt--from-hous--ing 10 and hub 50. O
An alternatiYe embodiment to the integral double back-seat 220 is illustrated in Figure 7. The upper stem mem-. ber 400 includes a removable backseat seal 402 and an inte-gral single backseat seal 404. In this embodiment clo-sure ring 160 may or may not be used. Ring 160 is no longer necessary because without integral double backseat 220 on upper stem member 80, upper .ctem member 80 could be received into bore 406.
Bonnet 408 includes an inwardly radially extending boss 410 having an upwardly facing beYeled shoulder 412 for engage~ent with backseat 402 and d downwardly facing beveled shoulder 414 for engagement with backseat 404.
Backseat 404 is dlsposed on upper stem member 400 above lug member 416 and in spaced relation with the open-10SS~os ing of the gate whereby in the raised or open flowway pO5i, . tion backseat 404 sealingly engages shoulder 414 creat-ing a metal-to-metal seal.
The upper portion 418 of upper stem member 400 has a reduced diameter creating upwardly facing annular shoul-der 42Q. Removable backseat 402 is slipped over reduced portion 418 being of such a diameter as to engage shoul-der 420. Spaced above the backseat 402, a distance equal to the thickness of backseat 402, i5 d;sposed an annular groove 422 for reCeiYin9 split ring 424. A snap ring 426 is received in annular groove 428 in the outer periphery of split ring 424 to hold split ring 424 in position in groove 422.
- Bonnet 408 includes a counterbore 430 coaxial with and adjacent to bore 406. ;Counterbore 430 is a stuffing box receiving a low~r compression ring~432~r-estin~g~on the~~
upwardly faG.ins annular shoulder 434 created by counter-bore 430, a packing 436, and a-follower compression ring 438 for actuation by gland 440 as gland 440 is threadingly received within counterbore 430.
A bleeder valve 442 is provided for communication with bore 406 by means of passa~e 444 to bleed pressure in order to change packing 436.
Backseat 402 has a downwardly extending annular seal flange 446 which has a lip 44~ curYing radially inwardly toward the stem 400. Backseat 402 is made of metal as for example steel. Backseat 402 is disposed on upper stem member 400 in such spaced relation that upon movement of the gate (not shown) to the closed flowway position, back--seat 402 sealingly engages shoulder 412 by means of seal flange 446 and the engagement of flange 446 on shoulder 412 111)55005 cams lip 448 into sea1ingly engagement with upper stem 400 to effect a metal-to-metal seal. Thus backseat 402 simul-taneouslY seals at two points, shoulder 412 and stem 400.
Backseat 404 is disposed on upper stem member 400 above lug member 416 and in spaced relation with the opening of the gate whereby in the raised or open flowway position backseat 404 sealingly engages shoulder 414 creating a metal-to-metal seal.
The above are9 of course, merely exemplary of possible changes or variations.
Because many varying and different embodiments may be made within the scope of the inventiYe concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptiYe requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.
Wha-t is claimed as invention is:-O O
o~ Y ~
It should be understood that the valve shown in the figures is normal acting in that during service of the valve it is anticipated that the valve will generally be closed to fluid flow. However the valve could obviously be reverse acting whereby during service the valve would generally be in the open position. ~he normal acting valve 1~ shown can be made reverse acting by merely modifying gate segments 70, 72 whereby transverse flow port 74 will register ~i~h openings 52, 53 when the gate is in the lower position rather than in the upper position as previously described.
Note that regardless of whether ~he valve is normal acting or reverse acting, the normal position (i.e. the general position of the valve during operation) will occur when the gate 40 is in the lower position.
Referring now to Figures 3, 4A and 4B, seals 230,-240 are received in annular grooves 232, 242 which cir-cumscribe seat hub 50 for sealing with surface 30 of hous-ing 10 on opposite sides of the sealant groove 64. Seal 230 is an elastomeric or plastic o-ring seal while seal 240 is an integral plastic-metal seal ring. Seal 240 in-p ~ f7 4/~ 0 ro e ~/e~7c cludes an annular metal ring 244 and a~e~fuer~e~ e~
or polymer such as the brand "Teflon",~"nylon"~ or other low-friction plastic annular ring 246. Groove 242 is located 1055005 , ~_ at the outer peripheral corner of hub 50 whereby groove 242 is two-sided with the opposing surfaces of counter-bore 22 providing the other two sides. Ideally the thick-ness of seal 240 will be equal to the length of the groove 242 with the tolerance being on the side of seal 240 hav-ing a greater thickness. Preferably the volume of groove 242 will substantially equal the volume of seal 240. The metal ring 244 has a close fit around groove 242 and is preferably press ~itted onto groove 242. Upon assembly as shown in Figures 1 and 4B gate seat members 32, 34 are inserted into closure member 18 whereby opposing seat hubs 50, 51 are inserted into corresponding counterbores 20 . 22 respectively. The leading edges 21, 23 at the entrances of counterbores 20, 22 respectively are beveled to facili-tate the assembly of hubs S0, 51. Upon assembly the metal ring 244 engages the bottom of groove 242 and shoulder 26 of counterbore 22 with plastic ring 24~ sub~tantially filling the remainder of groove 242.
The surfaces between shoulder 26 of counterbore 22 and the end face 243 of hub 50 cannot be matingly machined to effect a proper seal thereby requiring seal 240. How-ever, such machining may be accomplished for a proper metal-to-metal sealing engagement between the outer wall 73 of gate segment 72 and the inner surface 46 o~ gate seat mem-ber 34. Further it should be noted that to effect an ade-quate seal w~th seal 240, the area of the radially extend-ing annular wall 243 of groove 242 facing towards shoulder 26 of counterbore 22 must be less than the area of gate segment 72 encircled by sealant groove 68 exposed to line pressure through port 12. If the pressure on wall 243 due to sealant 56 is greater than the pressure on gate seg-~.055005 - /~3~
ment 72 due to line pressure, wall 243 will tend to move , - away from shoulder 26 thereby disengaging seal 240.
Referring now to Figures 1 an~ 2 gate 4D is recipro~
cated by means of a pressure balanced stem having an upper stem member 80 an,d a lower stem member 82. Lower stem member 82 includes a head 84 at its upper end which is enclosed between gate segments 70, 72 within counterbores 86, 88 in the inner faces of the lower portions of seg-ments 70, 72. Counterbores 86, 88 have sufficient axial length to permit l;mited axial movement of head 84 with respect to gate 40. Upper stem member 80 includes a T-shaped lug member 90,threaded or welded onto the lower end of upper stem member 80. The T-shaped lug member 90 is also enclosed between gate segments 70, 72 within cor-responding T-shaped and semi-circular counterbores 92, 94. This structure is old and forms no part of the present invention, therefore a more detailed description has not been made.
The lower end of the valve housing 10 is provided with a bore 95 coaxial with chamber 18 and with a coun-terbore 96 opening from the outer end of housing 10 form-ing a stuffing box for receiving lower stem member 82 and adapted to receive an annular packing 98 under compres-sion by a compression ring 100 and a gland 102 protrud-2~ ing from a lower closure cap 104 secured to the housing 10 by cap screws 106 or possibly by bolts. The housing 10 and closure cap 104 have corresponding mating annular grooves 108. 110 for receiving a lower ring gasket 112 to provide a metal-to-metal seal therebetween. The lower closure cap 104 has a bore 114 for slidingly receiving the lower stem member 82. A transverse pass~ge 116 in 1055~05 ~4 closure cap 104 provides communication between bore 114 and bleeder valve 118 to relieve any build up of line fluids in bore 114. The lower stem member 82 reciprocates in response to reciprocal movement of the gate 40, and pack-ing 98 serves to slidably seal about the lower stem mem-ber 82.
There is provided on the upper portion of lower stem member 82 below head 84 a metal seat ring 120 definlng a downwardly facing annular shoulder 122 surrounding the lower end of seat ring 120. Shoulder 122 is arcuate and cooperates with a bevelled seat 124 located at the entrance of bore 95 at the bottom of chamber 18 forming a line contact and a metal-to-metal seal therewith as will be described subsequently.
Referring to Figure 2 the upper end 128 of chamber 18 is adapted to be closed by means of a ~ub~ r-ca~-or bonnet 130 having a closure f~ange 132 secured to the upper end 134 of housing 10 by means of studs 136 or possibly by bolts or capscrews. Bonnet 130 has an axial bore 13B for receiving upper stem member 80. Upper stem member 80 has a double seal or backseat 220 radially projecting from and integral (i.e. the backseat 220 and stem 80 are one piece) with upper stem 80 thereby preventing any leakage behind the backseat 220. Backseat 220 has upwardly fac-ing and downwardly facing rounded shoulders 222, 224 and stress relief grooves 226, 228 adjacent thereto on each side of backseat 220. Shoulders 222, 224 are pl aced ap-proximately back to back to limit the longitudinal dimen-sion of bonnet 130.
Axial bore 138 includes an enlarged portion 154 hav-ing a diameter greater than the diameter of backseat 220 1LO55005 - ~ ~
for receiving same- Enlarged portion 154 terminates in a lower counterbore 15~ which is adapted to receive clo-sure ring 160 having an axîal stem - receiving bore 184 coaxial with closure cham~er 18 and bonnet bore 138. In the assembly of the valve upper stem member 80 is inserted into bore 138 with enlarged portion 154 receiving back-seat 220. Closure ring 160 then slides around upper stem member 80 behind backseat 220 and is rece;ved by counter-bore 158. It is at this time that lug member 90 is threaded onto upper stem member 80 for attachment with gate 40 and gate 40 is inserted between gate seat members 32, 34.
Closure ring 160 when received within counterbore 158 makes enlarged portion 154 into a chamber for the re-ciprocation of backseat 220. Enlarged portion 154 forms an internal downwardly facing beveled shoulder or seat 156 and ring 160 includes an upwardly facing beveled coni-~
cal shoulder or seat 186 at the upper end of bore 184 op-posing shoulder 156 after assembly.
Backseat 220 and seat ring 120 are formed in spaced-apart relation on upper stem 80 and on lower stem 82 re-spectively whereby in the closed flowway position, back-seat 220 will sealingly engage shoulder 186 providing a metal-to-metal seal therebetween and seat ring 120 will sealingly engage shoulder 124 providing a seal therebe-2', tween as the line fluid pressure forces seat ring 120 down-wardly by means of the limited axial movement of head 84 within counterbores 86, 88. Backseat 220 is also spaced on upper stem 80 whereby in the open flowway position seat 220 will sealingly engage shoulder 156 providing a metal-to-metal seal therebetween.
The closure ring 160 and its appurtenances are iden-1055005 ~
tical in construction and are arranged symmetrically on both upper and lower sides to permit reversability, so the description of one will be applicable to both. Ring 160 includes an upper and lower ring gasket groove 162, 164 for receiving upper and lower metal ring gaskets 166, 168 for sealing between the bonnet 130 and ring 160 and ring 160 and housing 10. Ring gasket groove 164 includes a downwardly and inwardly facing frusto-conical seat or shoulder 188, a downwardly facing inner annular shoulder 190, a downwardly and outwardly facing beveled conical shoulder 192, and a downwardly facing outer annular shoul-der 194. Shoulders 188, 190, 192 and 194 having decreas-- ing diameters respectively. The bottom portion of coun-terbore 158 includes a ring gasket groove 196-having the 1~ same features and dimensions as groove 164. Further ring gasket grooves 108, 110 in lower housing 10 and cap 104 have the sa~e features, dimensions and arrangements as grooves 196, 162. At the mouth of closure chamber 18 there is an inwardly extending annular boss 198 bounded by upper zo and lower frusto-conical shoulders or seats 200, 202. Shoul-der 200 mates and opposes shoulder 188 on closure ring 160. However, there is no corresponding upwardly facing annular shoulder on boss 198 opposing shoulder 194 on clo-sure ring 160.
Ring gaskets 112, 166 and 168 are identical in dimen-sion for interchangeability and therefore a description of one will apply to all.
Referring now to Figures 5A and 5B, ring gasket 168 is an annular ring having a T-shaped cross section. The stem 169 of the T-shaped cross section lies in a horizon-tal plane perpendicular to the axis of the bore 173 of the gasket 168 and the head 171 of the T-shaped cross section lies in a vertical plane parallel to the axis of the bore 173 The outer,peripheral annular edges 204, 206 of the head 171 are beveled for engagement wit~, annular seats or shoulders 188, 200 respectively. Gasket 168 is made of metal, prefer-ably steel.
Figure 5A illustrates the initial assembly position of gasket 168, before the gasket is compressed. The dimension X between closure ring 160 and housing 10 is approximately twice the dimension Y between stem 169 and shoulder 194 whereby as studs 136 are tightened, bonnet 130 and closure ring 160 will move downwardly the distance Y until annular sho,ulder 194 contacts the upwardly facing surface of stem 169 of gasket 168. This position is illustrated in Figure 5B at which time the dimension'Z between closure ring 160 and housing 10 is approximately one-half the dimension X. Upon tightening studs 136, gasket 168 is engaged-at points 208, 210 by closure ring 160 and is forced against shoulder 200 until the connection is complete as shown in Figure 1 and 2. As shown in Figure 2, gasket 168 has surface-to-surface contact at 211 with shoulder 200 of housing 10. Upon completion of the assembly gasket 168 engages closure ring 160 at points, the assemblage or loci of which, forms two annular rings, and gasket 168 engages housing 10 at points, the assemblage or locus of which, forms a single annular ring. During the assembly beveled edges 204, 206 are deformed against shoulders 188, 200 thereby establishing a high pressure metal-to-metal seal. Such deformation occurs because the median diameters of corners 204, 206 are slightly larger than the median diameters of shoulders 18B, 200.
1~ _ ~L055~)05 Standard metal ring gasket seals, as illustrated in Figures 5A and 5B at 212, which is slightly different than that shown in Figure 1, may be used in grooves 162, 196, and 1~8, 110 since the ring grooves are symmetrical with opposing surfaces. However, such gaskets cannot be used between bonnet 130 an:d housing 10 because there is no upwardly facing annular shoulder on boss 198 corresponding to shoulder 194 on ring 160 as previously shown.
rhe lack of this shoulder causes a standard gasket ring to be unstable, to rock under load and to misalign on shoulder 200 during assembly thereby providing a bad seal. If gasket 168 attempts to cock,-stem 169 engages shoulder 208 which forces gasket 168 back into alignment. To place a shoulder on boss 198 would require a larger housing 10 and a larger bonnet 130 to provide clearance for the installation and removal of ga~te 40 and gate seat members 32, 34.
Referring now to Figure 1, upper stem member 80 is provided' with an externally threaded portion 170 at its upper end which extends through stuffing box 142 wherein packing 144 se,rves ~to slidably seal about the stem member 80. An internally threaded drive nut 172 extends into cap 152 and is internally threaded at 174 to threadingly engage threaded portion 170 whereby rotation of the nut 172 wlll serve to raise and lower the closure member, i.e. stem members 80, 82 and gate 40, in ~ accordance with the direction of the rotation of the nut 172, in order to move the gate 40 between flowway-opening and flow-way-closing positions. The lower end of the nut 172 has an annular flange 173 which supports upper antifricition bearings 176 against the top of eap 152 and bears against lower anti-friction bearings 178 which rest on gland 150. The up-~05S005 per portion of the nut 172 which projects above the cap152, is provided with conventional flats at 180 for mount-ing an operating wheel 182 or other conventional operator, by which the gate 40 is actuated.
A bleeder valve 223 communicating with bore 138 by means of passage 225 through bonnet 130 provides a means to relieve bore 138 of any build up of line fluids when packing 144 is to be replaced.
The metal-to-metal seals at 156, 222;186, 224; and 120, 124 isolate packing 144 and 98 from long exposure to line fluids thereby preserving packing 98, 144 from deterioration.
Further the packing 98, 144 and such metal-to-metal seals provide dual sealing as a safety feature so if one seal blows or ruptures, there is a back up seal. Such metal-to-metal seals also provide the capability to remove and replace packings 98, 144 while the valve is under pressure although packings 98 and 144 are designed to operate throughout the life of the valve.
In operation as the valve is closed by operator 182, upper stem 80, gate 40, and lower stem 82 move downwardly into the lower position. Seat 120 on lower stem 82 seals with shoulder 124. Seat 120 is not mechanically actuated into sealing engagement but the line pressure forces seat 120 into sealing engagement with shoulder 124. Such move-ment by seat 120 is allowed by the limited axial movement permitted between head 84 and gate 40 which may be consid-ered a lost motion connection. Backseat 220 then engages shoulder 186 forming a metal-to-metal seal. After seat 120 engages shoulder 124, futher movement downwardly by upper stem 80 drives backseat 220 onto shoulder 186. As the valve is opened by operator 182, backseat 220 travels upwardly until backseat 220 sealingly engages 1055~S ~ ~ c -1 shoulder 156 providing a metal-to-:netal seal.
In closing or opening the valve5 bleeder valve 118 should be open whereby the line pressure will prov;de a ; balanced pressure force on both the lower stem 82 and up-per stem 80. Without such a balanced pressurized stem, the pressure on the upper stem 80 would place such a load on stem 80 as to require a very high torque to be used on stem 80 to open and close the Yalve. Bleeder valve 118 is used to bleed out pressure below lower stem 82 so as to prevent any upward pressure on stem 82.
It will be seen that when the gate 40 is moved to the flowway-closing position, shown in Figure 1, the dif-ferential line pressure across the closed valve will act on the downstream reservoir 54, the differential line pres-sure being exerted against the barrier 57 urging it in-wardly of reservoir 54 and simultaneously forcing seal-ant 56 from reservoir 54 into sealant groove 64 to seal off between outer surface 62 of the hub 50 and the sur-rounding wall 30 of chamber 18, and through passage 66 and recess 78 into sealant groove 68 provided at the inner surface of the seat member 72 to seal about the opening between the seat member 34 and the related closure seg-ment 72. Thus, sealant seals will automatically be pro-vided between both surfaces 46, 62 of the seat member 34 and the related portions of the closure segment 72 and the wall 30 of chamber 1~. The sealing action will be simultaneous.
Seals 230, 240 will be effective to prevent loss of sealant 56 from sealant groove 64. This permits effective sealing of the exterior of seat hub 50 while assuring against loss of sealant 56 due to any gap between the hub 50 and loss ~os body 10 at counterbore 22.
As line pressure reaches 30,000 psi, the yield strength of ordinary sealing materials is approached under confined streSs- Even below yield stress" there is substantial movement so that ordinary o-rings will not hold. The differ-ential pressure between chamber 18 and sealant groove 64 is very low but the differential pressure between groove 64 and port 14 is very high placing much pressure on seal 240. However, as high pressure is placed on plastic ring 246, metal ring ~44 is forced into the corner of groove 242 closing any gap or clearance a* the downstream juncture of the hub 50 and housing 10 and preventing the plastic ring 246 from extruding through any downstrearn clearance between the end face 243 of hub 50 and shoulder 26. The metal ring 244 can adapt itself to varying clearances be-tween the hub 50 and ~ousing 10 so that t~lese are not criti-Ocal. Thus the high press~ure.helps the seal.
Figures 6A and 6B illustrate an alternative sealing system for sealant groove 64 by sealing between surface 62 of hub 50 and wall 30 of counterbore 22. As shown in the unassembled position in Figure 6A, a plastic seal ring 300 is received in annular groove 302 in hub 50 interiorly of sealant grooYe 64. On the outer end portion of hub 50 is a reduced diameter portion 304 having an annular channel 306 on the outer end of portion 304. A plastic seal ring 308 is slipped over the portion 304 against annu-lar shoulder 310 formed by the reduction in diameter of portion 304. Two annular wedge or cam rings 312, 314 hav-i-ng Opposing upwardly and downwardly facing bevel 5 are slipped o~er portion 304. Then a split backup ring 316 hav~ng two semi-circular serttons and an inwardly extend-ing annular projection 318 is installed by inserting annu-lar projection 318 into channel 306. Projection 318 has a shorter length than the depth of channel 306. For as-sembly purposes the outer peripheral corner of backup ring 316 is chamfered for ease of insertion of hub 50 by contacting bevel 23 of housing 10. Further bevel 23 ~orces plastic rings 300, 308 into co~pressiQn within grooves 302 and portion 304.
; Upon expansion of the annular channel formed between reduced portion 304 and wall 30 due to line pressure, as shown in Figure 6B, wedge ring 312 will tend to cam onto wedge ring 314 creating a metal-to-metal sealing engage-ment ~etween portion 304 and ~all 30. Further such seal-ing engagement will prevent the extrusion of plastic seal ring 308 as shown in Figure 6B. Such camming or wedging o~-ring~-~12~ 14-~ccu~s-f-rom-the-rad-ial-sup~rt--from-hous--ing 10 and hub 50. O
An alternatiYe embodiment to the integral double back-seat 220 is illustrated in Figure 7. The upper stem mem-. ber 400 includes a removable backseat seal 402 and an inte-gral single backseat seal 404. In this embodiment clo-sure ring 160 may or may not be used. Ring 160 is no longer necessary because without integral double backseat 220 on upper stem member 80, upper .ctem member 80 could be received into bore 406.
Bonnet 408 includes an inwardly radially extending boss 410 having an upwardly facing beYeled shoulder 412 for engage~ent with backseat 402 and d downwardly facing beveled shoulder 414 for engagement with backseat 404.
Backseat 404 is dlsposed on upper stem member 400 above lug member 416 and in spaced relation with the open-10SS~os ing of the gate whereby in the raised or open flowway pO5i, . tion backseat 404 sealingly engages shoulder 414 creat-ing a metal-to-metal seal.
The upper portion 418 of upper stem member 400 has a reduced diameter creating upwardly facing annular shoul-der 42Q. Removable backseat 402 is slipped over reduced portion 418 being of such a diameter as to engage shoul-der 420. Spaced above the backseat 402, a distance equal to the thickness of backseat 402, i5 d;sposed an annular groove 422 for reCeiYin9 split ring 424. A snap ring 426 is received in annular groove 428 in the outer periphery of split ring 424 to hold split ring 424 in position in groove 422.
- Bonnet 408 includes a counterbore 430 coaxial with and adjacent to bore 406. ;Counterbore 430 is a stuffing box receiving a low~r compression ring~432~r-estin~g~on the~~
upwardly faG.ins annular shoulder 434 created by counter-bore 430, a packing 436, and a-follower compression ring 438 for actuation by gland 440 as gland 440 is threadingly received within counterbore 430.
A bleeder valve 442 is provided for communication with bore 406 by means of passa~e 444 to bleed pressure in order to change packing 436.
Backseat 402 has a downwardly extending annular seal flange 446 which has a lip 44~ curYing radially inwardly toward the stem 400. Backseat 402 is made of metal as for example steel. Backseat 402 is disposed on upper stem member 400 in such spaced relation that upon movement of the gate (not shown) to the closed flowway position, back--seat 402 sealingly engages shoulder 412 by means of seal flange 446 and the engagement of flange 446 on shoulder 412 111)55005 cams lip 448 into sea1ingly engagement with upper stem 400 to effect a metal-to-metal seal. Thus backseat 402 simul-taneouslY seals at two points, shoulder 412 and stem 400.
Backseat 404 is disposed on upper stem member 400 above lug member 416 and in spaced relation with the opening of the gate whereby in the raised or open flowway position backseat 404 sealingly engages shoulder 414 creating a metal-to-metal seal.
The above are9 of course, merely exemplary of possible changes or variations.
Because many varying and different embodiments may be made within the scope of the inventiYe concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptiYe requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.
Wha-t is claimed as invention is:-O O
o~ Y ~
Claims
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
moving means for moving said closure means between the open and closed positions;
first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members; and ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions; and single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions.
2. A valve according to claim 1 wherein said ring means includes a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member.
3. A valve according to claim 2 wherein said double edged metal seal ring has a substantially semi-circular cross section.
4. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
moving means for moving said closure means between the open and closed positions;
first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members;
ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions;
single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions;
said ring means including a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member;
said closure means includes two stress relief grooves; and said double edged metal seal ring is disposed on said closure means between said two stress relief grooves.
5. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
moving means for moving said closure means between the open and closed positions;
first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members;
ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions;
single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions;
said ring means including a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member; and said first cap member includes a bore having a first and a second metal seat;
said double edged metal seal ring sealingly engaging said first metal seat in the open position and said second metal seat in the closed position.
6. A valve according to claim 1 wherein said ring means is actuated by said moving means.
7. A valve according to claim 1 further comprising second-ary seals providing back up sealing for said ring means between said closure means and said first cap member.
8. A valve according to claim 1 further comprising means for bleeding line fluid from said first cap member.
9. A sealing system for valve members of a high pressure valve including a valve body having upstream and downstream conduits, a bonnet mounted on the body, an upper stem and a lower stem mounted within the valve body and bonnet and having a gate disposed therebetween, a gate seat disposed within the body for housing the gate, and the valve having a normal position for the gate, the improvement comprising:
metal-to-metal seals in the normal position between the bonnet and upper stem and the lower stem and body.
10. A sealing system according to claim 9 further in-cluding backup seals between the bonnet and upper stem and the lower stem and body.
11. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
means for moving said closure means between the open and closed positions;
first and second cap members for providing metal-to-metal sealing closures for said chamber;
said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members;
double seal ring means on said closure means providing a metal-to-metal sealing engagement with said first cap member in both the open and closed positions; and single seal ring means on said closure means providing a metal-to-metal sealing engagement with said valve body in one of the open and closed positions.
12. A valve according to claim 11 wherein double seal ring means includes a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member.
13. A valve according to claim 12 wherein said double edged metal seal ring has a substantially semi-circular cross section.
14. A valve according to claim 12 wherein said double edged metal seal ring is disposed on said closure means between two stress relief grooves.
15. A valve according to claim 11 wherein said first cap member includes a bore having a first and second metal seat; said double edged metal seal ring sealingly engaging said first metal seat in the open position and said second metal seat in the closed position.
16. A valve according to claim 15 wherein said single seal means includes a second metal seal ring integral with another portion of said closure means which extends into said second cap member; said valve body having a second metal seat at the passage of said other portion of said closure means from said chamber;
and said second metal seal ring sealingly engaging said second metal seat in one of the open and closed positions.
17. A valve according to claim 11 wherein in the normal position said double seal ring means shall initiate sealing engagement with said first cap member after the sealing en-gagement by said single seal ring with said valve body.
18. A valve according to claim 11 wherein in said double seal ring means is actuated by said moving means and said single seal ring means is actuated by line pressure.
19. A valve according to claim 11 further comprising secon-dary seals providing back up sealing for said double seal ring means and said single seal ring means between said closure means and said first cap member and said valve body.
20. A valve according to claim 11 further comprising means for bleeding line fluid from said first and second cap members.
21. The valve of claim 11 wherein said second cap member encloses said single seal ring means and includes seal means to provide a metal-to-metal sealing engagement with said valve body when said single seal ring means is in the other of the open and closed positions.
22. The valve of claim 21 wherein said seal means includes a bleeder valve and metal-to-metal seals with said valve body.
23. A high pressure valve including a valve body having inlet and outlet conduits and an upper aperture with a chamber therebetween and a bonnet covering the upper aperture, an upper stem and a lower stem mounted within the valve body and having a gate disposed therebetween, a gate seat disposed within the chamber and housing the gate, an open position where the gate permits flow through the conduits and a closed position where the gate blocks flow through the conduits, and moving means for moving the gate between the open and closed positions, the im-provement comprising:
first seal means disposed on the upper stem for sealing engagement with the valve body bonnet upon movement of the gate into one of the positions by the moving means; and second seal means disposed on the lower stem for sealing engagement with the valve body upon line pressure activation, said second seal means including means for permitting said second seal means to be actuated prior to the sealing engagement of said first seal means.
24. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions.
25. The valve of claim 29 wherein said seal ring means includes a first metal seal ring integral with said closure member having first means for sealingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means; and said lower portion having a second metal seat for sealingly engaging said second means.
26. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions;
said seal ring means including a first metal seal ring integral with said closure member having first means for seal-ingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means; and said lower portion having a second metal seat for sealingly engaging said second means;
said closure means including third means and said second metal seal ring including fourth means for reciprocally holding said second metal seal ring on said closure means.
27. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions;
said seal ring means includes a first metal seal ring inte-gral with said closure means having first means for sealingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means; and said lower portion having a second metal seat for sealingly engaging said second means;
said second metal seal ring includes means for initiating sealing engagement by said second means with said second metal seat in said one of said open or closed positions prior to said first means initiating sealing engagement with said first metal seat.
22. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions;
said seal ring means including a first metal seal ring integral with said closure means having first means for sealingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means;
said lower portion having a second metal seat for sealingly engaging said second means;
said second seal ring including initiation means for initiat-ing sealing engagement of said second means with said second metal seat upon actuation of said initiation means by line pres-sure and said first metal seal ring is actuated by said moving means.
29. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means being disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said lower portion in one of said open or closed positions;
said seal ring means including a metal seal ring for seal-ingly engaging said lower portion and being integral with said closure means; and said metal seal ring including means responsive to line pressure for actuating said sealing engagement of said metal seal ring and said lower portion.
30. In a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower apertures;
said closing means on said stems including a metal seal member on each of the upper and lower stems; and a metal seat surrounding each of the upper and lower apertures, each engage-able by one of said seal members.
31. In a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower apertures; and at least one of the closing means including holding means responsive to line pressure for maintaining said closing means in said position closing said lower aperture.
32. In a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower apertures; and a lost motion connection between the upper and lower stems allowing limited axial relative movement, whereby both of the upper and lower apertures can be held closed at the same time.
33. A valve, comprising:
a valve body having an inlet and an outlet and upper and lower apertures with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
a seat disposed within the chamber and housing a portion of said closure means;
moving means for moving said closure means between the open and closed positions;
first and second cap members closing said upper and lower apertures;
said closure means extending through said chamber and said upper and lower apertures and into said first and second cap members;
double seal ring means on said closure means providing a metal-to-metal sealing engagement with said first cap member in both the open and closed positions;
single seal ring means on said closure means providing a metal-to-metal sealing engagement with said valve body at said lower aperture in one of the open and closed positions; and said double seal ring means is actuated by said moving means and said single seal ring means is actuated by line pressure.
34. A valve, comprising:
a valve body having an inlet and an outlet and upper and lower apertures with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
a seat disposed within the chamber and housing a portion of said closure means;
moving means for moving said closure means between the open and closed positions;
first and second cap members for closing said upper and lower apertures;
said closure means extending through said chamber and said upper and lower apertures and into said first and second cap members;
double seal ring means on said closure means providing a metal-to-metal sealing engagement with said first cap member in both the open and closed positions;
single seal ring means on said closure means providing a metal-to-metal sealing engagement with said valve body at said lower aperture in one of the open and closed positions;
said double seal ring means being positioned to initiate sealing engagement with said first cap member after the sealing engagement by said single seal ring with said valve body.
35. A valve, comprising:
a valve body having an inlet and an outlet and upper and lower apertures with a chamber therebetween;
closure means for preventing flow from the inlet to the outlet in the closed position and permitting flow in the open position;
a seat disposed within the chamber and housing a portion of said closure means;
moving means for moving said closure means between the open and closed positions;
first and second cap members closing said upper and lower apertures;
said closure means extending through said chamber and said upper and lower apertures and into said first and second cap members;
double seal ring means on said closure means actuable by said moving means to provide a metal-to-metal sealing engagement with said first cap member in both the open and closed positions;
and line-pressure actuable single seal ring means on said clos-ure means providing a metal-to-metal sealing engagement with said valve body at said lower aperture in one of the open and closed positions.
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
moving means for moving said closure means between the open and closed positions;
first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members; and ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions; and single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions.
2. A valve according to claim 1 wherein said ring means includes a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member.
3. A valve according to claim 2 wherein said double edged metal seal ring has a substantially semi-circular cross section.
4. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
moving means for moving said closure means between the open and closed positions;
first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members;
ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions;
single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions;
said ring means including a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member;
said closure means includes two stress relief grooves; and said double edged metal seal ring is disposed on said closure means between said two stress relief grooves.
5. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
moving means for moving said closure means between the open and closed positions;
first and second cap members for providing sealing closures for said chamber, said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members;
ring means on said closure means for providing a metal-to-metal sealing engagement with said first cap member in at least one of the open and closed positions;
single seal ring means on said closure means for providing a metal-to-metal sealing engagement with said valve body in said one of the open and closed positions;
said ring means including a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member; and said first cap member includes a bore having a first and a second metal seat;
said double edged metal seal ring sealingly engaging said first metal seat in the open position and said second metal seat in the closed position.
6. A valve according to claim 1 wherein said ring means is actuated by said moving means.
7. A valve according to claim 1 further comprising second-ary seals providing back up sealing for said ring means between said closure means and said first cap member.
8. A valve according to claim 1 further comprising means for bleeding line fluid from said first cap member.
9. A sealing system for valve members of a high pressure valve including a valve body having upstream and downstream conduits, a bonnet mounted on the body, an upper stem and a lower stem mounted within the valve body and bonnet and having a gate disposed therebetween, a gate seat disposed within the body for housing the gate, and the valve having a normal position for the gate, the improvement comprising:
metal-to-metal seals in the normal position between the bonnet and upper stem and the lower stem and body.
10. A sealing system according to claim 9 further in-cluding backup seals between the bonnet and upper stem and the lower stem and body.
11. A valve comprising:
a valve body having an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
means for moving said closure means between the open and closed positions;
first and second cap members for providing metal-to-metal sealing closures for said chamber;
said closure means disposed in said chamber and extending through opposite sides of said chamber and into said first and second cap members;
double seal ring means on said closure means providing a metal-to-metal sealing engagement with said first cap member in both the open and closed positions; and single seal ring means on said closure means providing a metal-to-metal sealing engagement with said valve body in one of the open and closed positions.
12. A valve according to claim 11 wherein double seal ring means includes a double edged metal seal ring integral with a portion of said closure means which extends into said first cap member.
13. A valve according to claim 12 wherein said double edged metal seal ring has a substantially semi-circular cross section.
14. A valve according to claim 12 wherein said double edged metal seal ring is disposed on said closure means between two stress relief grooves.
15. A valve according to claim 11 wherein said first cap member includes a bore having a first and second metal seat; said double edged metal seal ring sealingly engaging said first metal seat in the open position and said second metal seat in the closed position.
16. A valve according to claim 15 wherein said single seal means includes a second metal seal ring integral with another portion of said closure means which extends into said second cap member; said valve body having a second metal seat at the passage of said other portion of said closure means from said chamber;
and said second metal seal ring sealingly engaging said second metal seat in one of the open and closed positions.
17. A valve according to claim 11 wherein in the normal position said double seal ring means shall initiate sealing engagement with said first cap member after the sealing en-gagement by said single seal ring with said valve body.
18. A valve according to claim 11 wherein in said double seal ring means is actuated by said moving means and said single seal ring means is actuated by line pressure.
19. A valve according to claim 11 further comprising secon-dary seals providing back up sealing for said double seal ring means and said single seal ring means between said closure means and said first cap member and said valve body.
20. A valve according to claim 11 further comprising means for bleeding line fluid from said first and second cap members.
21. The valve of claim 11 wherein said second cap member encloses said single seal ring means and includes seal means to provide a metal-to-metal sealing engagement with said valve body when said single seal ring means is in the other of the open and closed positions.
22. The valve of claim 21 wherein said seal means includes a bleeder valve and metal-to-metal seals with said valve body.
23. A high pressure valve including a valve body having inlet and outlet conduits and an upper aperture with a chamber therebetween and a bonnet covering the upper aperture, an upper stem and a lower stem mounted within the valve body and having a gate disposed therebetween, a gate seat disposed within the chamber and housing the gate, an open position where the gate permits flow through the conduits and a closed position where the gate blocks flow through the conduits, and moving means for moving the gate between the open and closed positions, the im-provement comprising:
first seal means disposed on the upper stem for sealing engagement with the valve body bonnet upon movement of the gate into one of the positions by the moving means; and second seal means disposed on the lower stem for sealing engagement with the valve body upon line pressure activation, said second seal means including means for permitting said second seal means to be actuated prior to the sealing engagement of said first seal means.
24. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions.
25. The valve of claim 29 wherein said seal ring means includes a first metal seal ring integral with said closure member having first means for sealingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means; and said lower portion having a second metal seat for sealingly engaging said second means.
26. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions;
said seal ring means including a first metal seal ring integral with said closure member having first means for seal-ingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means; and said lower portion having a second metal seat for sealingly engaging said second means;
said closure means including third means and said second metal seal ring including fourth means for reciprocally holding said second metal seal ring on said closure means.
27. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions;
said seal ring means includes a first metal seal ring inte-gral with said closure means having first means for sealingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means; and said lower portion having a second metal seat for sealingly engaging said second means;
said second metal seal ring includes means for initiating sealing engagement by said second means with said second metal seat in said one of said open or closed positions prior to said first means initiating sealing engagement with said first metal seat.
22. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said upper and lower portions in one of said open or closed positions;
said seal ring means including a first metal seal ring integral with said closure means having first means for sealingly engaging said upper portion and a second metal seal ring having second means for sealingly engaging said lower portion and being mounted on said closure means, said upper portion having a first metal seat for sealingly engaging said first means;
said lower portion having a second metal seat for sealingly engaging said second means;
said second seal ring including initiation means for initiat-ing sealing engagement of said second means with said second metal seat upon actuation of said initiation means by line pres-sure and said first metal seal ring is actuated by said moving means.
29. A valve, comprising:
a valve body having an upper and lower portion and an inlet and an outlet with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position, said closure means being disposed in said chamber and extending through opposite sides of said chamber;
moving means for moving said closure means between the open and closed positions;
seal ring means on said closure means for providing a metal-to-metal sealing engagement with said lower portion in one of said open or closed positions;
said seal ring means including a metal seal ring for seal-ingly engaging said lower portion and being integral with said closure means; and said metal seal ring including means responsive to line pressure for actuating said sealing engagement of said metal seal ring and said lower portion.
30. In a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower apertures;
said closing means on said stems including a metal seal member on each of the upper and lower stems; and a metal seat surrounding each of the upper and lower apertures, each engage-able by one of said seal members.
31. In a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower apertures; and at least one of the closing means including holding means responsive to line pressure for maintaining said closing means in said position closing said lower aperture.
32. In a valve comprising a body having inlet and outlet conduits and upper and lower stem apertures with a chamber there-between, a closure member disposed in said chamber and movable between an open position wherein fluid flow is permitted between said inlet and outlet conduits and a closed position wherein such flow is prevented, upper and lower stems on said closure member extending through said upper and lower apertures, respectively, an upper bonnet covering the upper aperture, a lower cap covering the lower aperture, and means connected to one of said stems adapted to move said stems longitudinally and thereby move said closure member between open and closed positions, the improvement which comprises:
closing means on said stems movable, upon movement of said closure member to one of said open and closed positions, to a position closing both of said upper and lower apertures; and a lost motion connection between the upper and lower stems allowing limited axial relative movement, whereby both of the upper and lower apertures can be held closed at the same time.
33. A valve, comprising:
a valve body having an inlet and an outlet and upper and lower apertures with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
a seat disposed within the chamber and housing a portion of said closure means;
moving means for moving said closure means between the open and closed positions;
first and second cap members closing said upper and lower apertures;
said closure means extending through said chamber and said upper and lower apertures and into said first and second cap members;
double seal ring means on said closure means providing a metal-to-metal sealing engagement with said first cap member in both the open and closed positions;
single seal ring means on said closure means providing a metal-to-metal sealing engagement with said valve body at said lower aperture in one of the open and closed positions; and said double seal ring means is actuated by said moving means and said single seal ring means is actuated by line pressure.
34. A valve, comprising:
a valve body having an inlet and an outlet and upper and lower apertures with a chamber therebetween;
closure means for preventing flow in the closed position and permitting flow in the open position;
a seat disposed within the chamber and housing a portion of said closure means;
moving means for moving said closure means between the open and closed positions;
first and second cap members for closing said upper and lower apertures;
said closure means extending through said chamber and said upper and lower apertures and into said first and second cap members;
double seal ring means on said closure means providing a metal-to-metal sealing engagement with said first cap member in both the open and closed positions;
single seal ring means on said closure means providing a metal-to-metal sealing engagement with said valve body at said lower aperture in one of the open and closed positions;
said double seal ring means being positioned to initiate sealing engagement with said first cap member after the sealing engagement by said single seal ring with said valve body.
35. A valve, comprising:
a valve body having an inlet and an outlet and upper and lower apertures with a chamber therebetween;
closure means for preventing flow from the inlet to the outlet in the closed position and permitting flow in the open position;
a seat disposed within the chamber and housing a portion of said closure means;
moving means for moving said closure means between the open and closed positions;
first and second cap members closing said upper and lower apertures;
said closure means extending through said chamber and said upper and lower apertures and into said first and second cap members;
double seal ring means on said closure means actuable by said moving means to provide a metal-to-metal sealing engagement with said first cap member in both the open and closed positions;
and line-pressure actuable single seal ring means on said clos-ure means providing a metal-to-metal sealing engagement with said valve body at said lower aperture in one of the open and closed positions.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US51236874A | 1974-10-04 | 1974-10-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1055005A true CA1055005A (en) | 1979-05-22 |
Family
ID=24038805
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA236,870A Expired CA1055005A (en) | 1974-10-04 | 1975-10-02 | Single double backseat |
Country Status (3)
| Country | Link |
|---|---|
| CA (1) | CA1055005A (en) |
| DE (1) | DE2544352A1 (en) |
| GB (1) | GB1503022A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4340204A (en) * | 1976-02-06 | 1982-07-20 | Smith International, Inc. | High pressure gate valve with preloaded, stacked, solid lubricated stem seals |
| US4363465A (en) * | 1976-06-16 | 1982-12-14 | Smith International, Inc. | Extreme temperature, high pressure balanced, rising stem gate valve with super preloaded, stacked, solid lubricated, metal-to-metal seal |
| US5730419A (en) * | 1994-07-12 | 1998-03-24 | Fmc Corporation | Dual backseat valve assembly |
| ITPR20070087A1 (en) * | 2007-11-14 | 2009-05-15 | Biffi Italia | GATE VALVE WITH INTEGRATED HYDRAULIC ACTUATOR FOR SUBMARINE USE |
-
1975
- 1975-10-02 CA CA236,870A patent/CA1055005A/en not_active Expired
- 1975-10-02 GB GB4030375A patent/GB1503022A/en not_active Expired
- 1975-10-03 DE DE19752544352 patent/DE2544352A1/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| GB1503022A (en) | 1978-03-08 |
| DE2544352A1 (en) | 1976-04-15 |
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