CN113669471A

CN113669471A - Ball screw driven ultrahigh-pressure sand-prevention type tailless rising stem flat valve

Info

Publication number: CN113669471A
Application number: CN202111078654.2A
Authority: CN
Inventors: 姜玉虎; 杨培建; 张庭高
Original assignee: JIANGSU HONGTAI PETROCHEMICAL MACHINERY CO Ltd
Current assignee: JIANGSU HONGTAI PETROCHEMICAL MACHINERY CO Ltd
Priority date: 2020-08-31
Filing date: 2020-08-31
Publication date: 2021-11-19
Also published as: CN113339539A; CN111963105A

Abstract

The utility model provides a ball screw driven superhigh pressure sand control type does not have tail-rod rising stem wafer valve, characterized by: a hand wheel rotating part is arranged above the valve cover part and the valve rod part, a ball screw pair connected with the valve rod is arranged in the hand wheel rotating part, and a locking mechanism which allows or prohibits the hand wheel and a screw nut to rotate is additionally arranged on one side of the hand wheel rotating part; a set of combined sealing element overlapped by a plurality of layers of non-rubber sealing rings with different sections is arranged at the contact part of the upper end of the valve body and the central hole of the valve cover part and the valve rod; a pair of sand control plates which are filled in the valve cavities at the two sides of the flashboard and are provided with elastic rubber rings are symmetrically arranged in the cylindrical valve cavity of the valve body and below the valve seat. The flat valve without the tail rod and the rising stem has the advantages of small volume, switch display, low price and convenient maintenance, and realizes new functions of easy operation, reliable sealing, wear resistance, corrosion resistance, sand prevention, blockage prevention and the like, thereby being more suitable for being used under severe working conditions such as ultrahigh pressure fracturing operation and the like.

Description

Ball screw driven ultrahigh-pressure sand-prevention type tailless rising stem flat valve

Technical Field

The invention relates to a manual rising stem flat valve used in petroleum machinery and other industries.

Background

The manual rising stem flat valve without tail stem is a large-caliber gate valve commonly used in high and medium pressure petroleum drilling and production equipment, and has the advantages of small product volume, light weight, low price, direct display of valve opening and closing conditions and the like. But along with the continuous increase of oil gas well degree of depth, the continuous improvement of operating pressure grade, the manual rising stem wafer valve of present sand prevention mould no tail pole has been difficult to be competent in the operation requirement of superhigh pressure operating mode, its main problem: firstly, the valve has no tail rod to carry out pressure balance, so that the valve rod bears the medium pressure in one direction; in addition, the ball screw pair has small friction coefficient and no self-locking function; therefore, under the ultrahigh pressure working condition, if the valve is driven by the trapezoidal thread pair with the self-locking function, the valve cannot be operated by a normal person. Secondly, the sand control plates additionally arranged on the two sides of the gate plate are almost flat plates, the rigidity is insufficient, and the elastic or plastic deformation is easily generated under the ultrahigh pressure working condition, so that part of sand-containing medium enters the valve cavity to cause sand blocking accidents; in addition, no active fitting force exists between the sand control plate and the gate plate, and the fixed free gap formed by precision machining of the sand control plate is increased along with the increase of the working time and the deformation of parts, so that a gap is provided for the sand-containing medium to enter the valve cavity. Thirdly, a valve cover of the flat valve and a rubber combined sealing element used at a valve rod are difficult to meet the requirements of ultrahigh pressure working conditions and frequent operation; a few valve rod combined sealing elements using composite materials have poor sealing performance and service life due to few layers or poor matching. Fourthly, when the valve is closed to the end, operators are required to rotate a hand wheel about a circle according to the pitch of the valve rod and the design allowance so as to enable the bottom surface of the gate plate to be separated from the valve body and the lower end of the valve rod to be in a floating state, and the valve seat sealing ring with limited elasticity can generate the best sealing effect under the condition of no external force stress; however, normally functioning flat valves often leak when closed due to improper operation for a number of reasons.

Disclosure of Invention

The invention aims to provide a tailless manual rising stem flat valve which is driven by a ball screw pair, is suitable for ultrahigh pressure working conditions and has excellent sand prevention, sealing and leakage prevention functions.

The invention is formed by combining a hand wheel rotating part, a valve cover part, a valve body, a valve rod, a flashboard, a valve seat, a sand-proof plate, a guide plate part, a matched sealing element and a matched connecting piece; the characteristics are as follows: a hand wheel rotating part is arranged above the valve cover part and the valve rod part, a ball screw pair connected with the valve rod is arranged in the hand wheel rotating part, and a locking mechanism which allows or prohibits the hand wheel and a screw nut to rotate is additionally arranged on one side of the hand wheel rotating part; a set of combined sealing element overlapped by a plurality of layers of non-rubber sealing rings with different sections is arranged at the contact part of the upper end of the valve body and the central hole of the valve cover part and the valve rod; a pair of sand control plates which are filled in the valve cavities at the two sides of the flashboard and are provided with elastic rubber rings are symmetrically arranged in the cylindrical valve cavity of the valve body and below the valve seat.

Because the invention adopts the ball screw pair to drive firstly, the switch resistance of the valve can be greatly reduced; the hand wheel is positioned in the middle of the hand wheel rotating part, so that the height of the valve can be reduced, and the product volume is reduced; a transparent shield is matched with a lead screw in the ball screw pair above the hand wheel, so that the opening and closing conditions of the valve can be visually displayed; a locking mechanism which allows or prohibits the rotation of the hand wheel and the lead screw nut is added on one side of the hand wheel rotating part, so that the abnormal situation that when the valve is closed, the gate plate and the valve rod push the ball screw pair without self-locking capacity to rotate under the pressure action in the valve cavity, and then the valve is automatically opened can be avoided; but also can make the flashboard leave a floating gap after the valve is closed so as to improve the sealing effect of the valve. A set of combined sealing element formed by overlapping a plurality of layers of non-rubber sealing rings with different cross sections is arranged at the contact position of the central hole of the valve cover part and the valve rod at the upper end of the valve body, and the sealing functions of various composite sealing rings are organically combined, so that the effects of multiple sealing and super compression resistance, wear resistance and corrosion resistance are achieved. A pair of sand control plates which are filled in the valve cavities at the two sides of the gate plate and are provided with elastic rubber rings are symmetrically arranged in the valve cavities and below the valve seat, so that the strength of the sand control plates can be improved, the deformation space of the sand control plates can be eliminated, the elasticity generated by the rectangular sealing rings in the sand control plate parts can be utilized, the sand control plates can be always actively and tightly attached to the gate plate, and no gap for sand-containing media to enter the valve cavities is reserved.

Drawings

FIG. 1 is a schematic view in full section of the overall valve structure of the present invention in its fully open position;

FIG. 2 is an enlarged schematic cross-sectional view taken along line A-A of the joint of the valve body, the gate plate and the sand control plate in FIG. 1;

FIG. 3 is an enlarged view of a portion of the combined seal at the point where the bonnet contacts the valve stem in accordance with the present invention;

FIG. 4 is a schematic perspective view of an enlarged sand control plate part according to the present invention;

FIG. 5 is an enlarged cross-sectional view of an elastic rubber ring matched with the sand control plate in the invention;

fig. 6 is an enlarged view of a small part of the locking mechanism of the hand wheel rotating part of the present invention when locked.

The names of the components indicated by the reference numerals in the drawings are as follows:

1. the sealing structure comprises a valve body, 2, a sealing gasket ring, 3, a valve cover, 4, a stud nut, 5, a bearing housing, 6, a locking mechanism, 601, an elastic bolt, 602, a fixed sleeve, 603, a compression spring, 604, a slotted nut, 605, a pull ring, 606, a set screw, 7, a rotating shaft sleeve, 8, a hand wheel, 9, a transparent shield, 10, an oil cup, 11, a ball screw pair, 12, an inner hexagon screw, 13, a screw gasket, 14, an O-shaped sealing ring, 15, a thrust bearing, 16, a cylindrical pin, 17, a combined sealing element, 18, a set screw, 19, a valve rod, 20, a grease injection valve, 21, a gate plate, 22, a valve seat, 23, an inner sealing ring, 24, a valve ring, 25, an outer sealing plate, 26, an elastic rubber ring, 27 and a guide plate.

Detailed Description

The following further describes embodiments of the present invention with reference to the accompanying drawings:

in the figures 1 and 2, the valve body 1 is taken as a carrier, and the valve body is formed by combining a hand wheel rotating part, a valve cover part, a valve rod 19, a flashboard 21, a valve seat 22, a sand-proof plate 25, a guide plate 27 part, a matched sealing part and a matched connecting part from top to bottom to form a functional body for controlling the opening and closing of a pipeline.

The middle of the valve body 1 is a cylindrical body which is provided with a cylindrical valve cavity blind hole, the left end and the right end are provided with extended neck flanges, and the center of the flange is provided with a left channel hole and a right channel hole which are vertically intersected with the valve cavity hole; the junction of the left and right channel holes and the cylindrical valve cavity hole is expanded with a mounting hole of the valve seat 22; the end surfaces of the left and right neck-mounted flanges are respectively provided with a trapezoidal gasket ring groove and uniformly distributed stud holes for external connection; a trapezoidal gasket ring groove and uniformly distributed threaded blind holes are processed on the cylindrical body of the valve body 1 so as to be connected with a valve cover component by a sealing gasket ring 2 and uniformly distributed stud nuts 4.

The valve cover component of the invention consists of a valve cover 3, a combined sealing member 17 and a grease injection valve 20. The valve cover 3 is a part with a large end and a small end; the small end is a hollow screw cylinder with a tool withdrawal groove and a small diameter, the large end is a hollow cylinder with a large diameter, and a trapezoidal cushion ring groove and uniformly distributed screw cylinder holes are processed below the large end; the center of the valve cover 3 is provided with threaded holes and cylindrical holes with different diameters, and the small end surface of the valve cover is downwards provided with a threaded hole and a cylindrical step hole with smaller diameters and used for installing a combined sealing element 17; the big end surface is upward provided with a big cylindrical hole which has the same diameter with the valve cavity and a certain depth and is used as an extension part of the valve cavity; on the side wall of the big end of the valve cover 3, a stepped hole with a conical thread at the inlet is drilled, and a grease injection valve 20 is arranged in the hole and used for injecting sealing grease into the valve so as to improve the sealing performance of the valve.

In fig. 3, the combined sealing element 17 of the present invention is formed by stacking and combining a packing gland, a layer of metal gasket, four layers of sealing rings with different cross sections, and a layer of inverted-t-shaped retainer ring; the sealing ring with the square V-shaped groove section is arranged on the uppermost layer, the sealing ring with the symmetrical wing-shaped section is arranged on the second layer, and the composite sealing ring with the short handle and the butt-shaped section is arranged on the third layer; the fourth layer is a composite sealing ring with a shape of an intermediate section of the long handle. When in superposition: the V-shaped groove below the sealing ring on the uppermost layer is inosculated with the tip end above the second layer of sealing ring, the V-shaped groove and the square groove below the second layer of sealing ring are inosculated with the tip end and the short handle above the third layer of composite sealing ring, and the long handle above the fourth layer of composite sealing ring and the reverse T-shaped check ring is respectively inserted into the inner cavities below the butt-shaped cross sections of the third layer of composite sealing ring and the fourth layer of composite sealing ring to seal the valve rod 19. In addition, in order to deal with the ultrahigh pressure working condition, the whole body of the square V-shaped groove section sealing ring, the symmetrical wing-shaped section sealing ring and the inverted T-shaped check ring in the combined sealing piece 17 and the shells of the short handle and intermediate section composite sealing ring and the long handle and intermediate section composite sealing ring are all molded by special engineering plastics of polyether ether ketone (PEEK); annular springs with tops bent into circular arcs and V-shaped sections are arranged in the inner cavities of the butt-shaped sections of the short handle butt-shaped section composite sealing ring and the long handle butt-shaped section composite sealing ring; the ring springs are all formed by punching and welding nonmagnetic alloy thin steel plates of Elgiloy.

A valve rod 19, a flashboard 21 and guide plates 27 positioned in front and back of the flashboard 21 are arranged in a valve cavity formed by central holes of the valve body 1 and the valve cover component from top to bottom; the upper end of the flashboard 21 is connected with a T-shaped joint at the lower end of the valve rod 19 by a T-shaped groove; the front and rear planes of the shutter plate 21 are provided with vertically through elongated grooves, and guide plates 27 formed by punching thin steel plates are installed in the grooves to prevent the shutter plate 21 from shifting forward and backward. The valve seat 22 and the inner sealing ring 23 and the outer sealing ring 24 which are matched with the valve seat are symmetrically arranged on two sides of the valve cavity inner gate plate 21; the cylindrical passage hole below the shutter 21, the valve seats 22 on both sides and the passage hole on the valve body 1 determine the opening or closing of the valve through the change of the relative positions. On both sides of the gate plate 21 and below the valve seat 22, a sand control plate 25 with a pair of elastic rubber rings 26 is symmetrically arranged to prevent sand-containing medium from entering the valve cavity.

In fig. 4 and 5, the sand control plate 25 is a square thick steel plate with a plane on one side and an arc surface on one side, the plane is attached to the gate plate 21, and the arc surface is attached to a valve cavity hole in the valve body 1; an arc-shaped notch is arranged on the steel plate and is used for being connected with the valve seat 22; the junction between the lower surface of the steel plate and the arc surface is a large chamfer so as to be convenient for installation in the valve cavity; a through hole with a small diameter is drilled on the perpendicular bisector of the plane and the arc surface at the two sides of the sand control plate 25 and close to the arc-shaped notch, so that the pressure at the inner side and the pressure at the outer side are balanced; a square groove with four arc angles is symmetrically processed on the arc surface of the sand control plate 25 and below the arc-shaped notch, and an elastic rubber ring 26 is arranged in the square groove and can generate elastic force for pushing the sand control plate 25 to be tightly attached to the gate plate 21 after contacting with the wall of the valve cavity. The outer edge of the cross section of the elastic rubber ring 26 is a convex arc edge, the inner edge of the cross section of the elastic rubber ring is provided with a semicircular groove, and the other two edges are mutually parallel straight edges; the elastic rubber ring 26 is integrally made of FKM fluororubber or HNBR high-saturation hydrogenated nitrile rubber so as to cope with severe working conditions.

In addition, in order to deal with the ultrahigh pressure working condition, the inner sealing ring 23 and the outer sealing ring 24 which are matched with the valve seat 22 are both composite elastic sealing rings: the radial sections of the outer layer main ring are U-shaped, and are molded by special engineering plastics of polyether ether ketone (PEEK); the U-shaped openings of the main rings are internally provided with metal spring rings with V-shaped radial sections; the V-shaped metal spring rings are all provided with polymer material rings with rectangular radial sections and four chamfered edges. Difference between the inner seal ring 23 and the outer seal ring 24: firstly, the diameters are different; the opening of the U-shaped main ring of the inner sealing ring 23 faces inwards, and the opening of the U-shaped main ring of the outer sealing ring 24 faces outwards.

A hand wheel rotating part is arranged at the upper end of the valve body 1 and above the valve cover part. The hand wheel rotating part consists of a bearing housing 5, a locking mechanism 6, a rotating shaft sleeve 7, a hand wheel 8, a transparent shield 9, an oil cup 10, a ball screw pair 11, an inner hexagon screw 12, a screw washer 13, an O-shaped sealing ring 14, a thrust bearing 15 and a set screw 18. The upper and lower surfaces of a convex waistcoat at the lower part of the rotating shaft sleeve 7 are respectively provided with a thrust bearing 15, and after a bearing housing 5 and an O-shaped sealing ring 14 are used for wrapping, a threaded hole at the bottom surface of the bearing housing 5 is connected with a screw cylinder at the upper end of the valve cover 3 together, and then is fixed by a set screw 18; the hand wheel 8 is arranged at the hexagonal prism at the upper part of the rotating shaft sleeve 7 by a hexagonal hole at the center of the hub of the hand wheel, a screw nut in the ball screw pair 11 is arranged in a central hole at the upper end of the rotating shaft sleeve 7 and is fixed together by uniformly distributed inner hexagonal screws 12; the transparent protective cover 9 is sleeved at the upper end of the ball screw pair 11 and is fixed on the hub of the hand wheel 8 by uniformly distributed screw washers 13. The transparent protective cover 9 is made of engineering plastics, and the surface of the cylinder is marked with opening and closing characters and percentage scale lines, and is matched with a shaft end check ring at the upper end of the ball screw pair 11 to display the opening and closing conditions of the valve. The ball screw pair 11 adopts an internal circulation series and neck flange type screw nut structure: the central hole of the screw nut is internally provided with a steel ball and a screw rod which roll circularly, and the upper end of the screw rod is fixed with a shaft end check ring by a screw washer to prevent the screw nut and the steel ball inside from slipping; the lower end of the screw rod is provided with a cylinder and a screw head with radial pin holes, and after the screw and the cylindrical pin 16 are connected with the upper end of the valve rod 19, the rotating torque on the hand wheel 8 can be converted into the driving force for the up-and-down movement of the gate plate 21 through the ball screw pair 11 and the valve rod 19.

In fig. 6, in order to prevent the ball screw assembly 11 without self-locking capability from automatically rotating and opening the valve, and simultaneously prevent the deviation of the gate plate 21 from affecting the sealing performance of the inner sealing ring 23 and the outer sealing ring 24 on the left and right sides of the valve seat 22; a blind hole is drilled on the raised waistcoat circumference at the lower part of a rotary shaft sleeve 7; a locking mechanism 6 which can be manually operated is installed and welded firmly in a threaded hole on one side of the bearing housing 5 corresponding to the blind hole. When the bolt in the locking mechanism 6 is in butt joint with the blind hole on the sleeveless jacket of the rotating shaft sleeve 7 and locked, the hand wheel 8 and the ball screw pair 11 can be prevented from rotating, and a floating gap is reserved after the valve is closed for the flashboard 21.

The locking mechanism 6 of the present invention is composed of an elastic bolt 601, a fixing sleeve 602, a compression spring 603, a slotted nut 604, a pull ring 605 and a set screw 606. The fixed sleeve 602 is a section of thin steel pipe, external threads are processed at two ends of the steel pipe, one end of the steel pipe is connected with a threaded hole at one side of the bearing housing 5 and is welded and fixed, and the other end of the steel pipe is connected with a slotted nut 604 and is fixed by a set screw 606; an elastic bolt 601 and a compression spring 603 are arranged in a central hole of the fixed sleeve 602; the thick end of the elastic bolt 601 faces inwards, the thin end penetrates through the central holes of the compression spring 603 and the slotted nut 604, and then the thin end radial small hole is buckled by the pull ring 605 to form an integral small part. The periphery of the slotted nut 604 may be machined into a hexagonal prism or knurled cylinder to facilitate assembly; a threaded hole with a tool withdrawal groove is processed at the inward end of the fixing sleeve and is connected with the fixing sleeve 602; a small radial threaded hole is drilled in the circumferential wall of the threaded hole and used for installing a set screw 606; a small through hole is processed at the outward end of the elastic bolt so as to allow the thin end of the elastic bolt 601 to pass through and block the compression spring 603; a cross-shaped groove with a depth of one depth is formed on the central line of the outer end face of the small through hole and is used in cooperation with the pull ring 605. When the elastic bolt 601 and the pull ring 605 are rotated ninety degrees and placed in the deep groove, the blind hole can be automatically found for locking; pulling out the elastic bolt 601 and the pull ring 605 and rotating them ninety degrees to locate them in the shallow groove allows the handwheel 8 and the ball screw pair 11 to operate normally.

The foregoing shows and describes the general principles, principal features, and principal advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments illustrated above, and that the individual components or combinations of the seal member 17 and the resilient rubber ring 26, among others, may be modified or adapted in shape or material without departing from the spirit and scope of the invention as hereinafter claimed.

Claims

1. An ultrahigh pressure sand-prevention type tail-rod-free rising stem flat valve driven by a ball screw is formed by combining a hand wheel rotating part, a valve cover part, a valve body, a valve rod, a flashboard, a valve seat, a sand-prevention plate, a guide plate part, a matched sealing element and a matched connecting piece; the method is characterized in that: a hand wheel rotating part is arranged above the valve cover part and the valve rod part, a ball screw pair connected with the valve rod is arranged in the hand wheel rotating part, and a locking mechanism which allows or prohibits the hand wheel and a screw nut to rotate is additionally arranged on one side of the hand wheel rotating part; a set of combined sealing element overlapped by a plurality of layers of non-rubber sealing rings with different sections is arranged at the contact part of the upper end of the valve body and the central hole of the valve cover part and the valve rod; a pair of sand control plates which are filled in the valve cavities at the two sides of the flashboard and are provided with elastic rubber rings are symmetrically arranged in the cylindrical valve cavity of the valve body and below the valve seat.

2. The ball screw driven ultrahigh pressure sand control type tailless rising stem flat valve according to claim 1, which is characterized in that: the combined sealing element is formed by superposing and combining a packing gland, a layer of metal gasket, four layers of sealing rings with different sections and a layer of inverted T-shaped retainer ring; the sealing ring with the square V-shaped groove section is arranged on the uppermost layer, the sealing ring with the symmetrical wing-shaped section is arranged on the second layer, and the composite sealing ring with the short handle and the butt-shaped section is arranged on the third layer; the fourth layer is a composite sealing ring with a shape of an intermediate section of the long handle.

3. The ball screw driven ultrahigh pressure sand control type tailless rising stem flat valve according to claim 2, which is characterized in that: the sealing ring with square V-shaped groove section, the sealing ring with symmetrical wing-shaped section and the inverted T-shaped check ring in the combined sealing element, and the shells of the composite sealing ring with short handle and long handle and butt section are all molded by special engineering plastics of polyether ether ketone (PEEK); annular springs with tops bent into circular arcs and V-shaped sections are arranged in the inner cavities of the butt-shaped sections of the short handle butt-shaped section composite sealing ring and the long handle butt-shaped section composite sealing ring; the ring springs are all formed by punching and welding nonmagnetic alloy thin steel plates of Elgiloy.

4. The ball screw driven ultrahigh pressure sand control type tailless rising stem flat valve according to claim 1, which is characterized in that: the sand control plate is a square thick steel plate with a plane at one side and an arc surface at one side, an arc notch is arranged on the steel plate, and a large chamfer angle is arranged at the junction of the lower surface of the steel plate and the arc surface; drilling a through hole with a small diameter on the perpendicular bisector of the planes and the arc surfaces on the two sides of the sand control plate and at the position close to the arc-shaped notch; a square groove with four arc angles is symmetrically processed on the arc surface of the sand control plate and below the arc notch.

5. The ball screw driven ultrahigh pressure sand control type tailless rising stem flat valve according to claim 1, which is characterized in that: the outer edge of the cross section of the elastic rubber ring is a convex arc edge, the inner edge of the cross section of the elastic rubber ring is provided with a semicircular groove, and the other two edges are mutually parallel straight edges; the elastic rubber ring is integrally made of FKM fluororubber or HNBR high-saturation hydrogenated nitrile rubber.

6. The ball screw driven ultrahigh pressure sand control type tailless rising stem flat valve according to claim 1, which is characterized in that: the locking mechanism is formed by combining an elastic bolt, a fixed sleeve, a compression spring, a slotted nut, a pull ring and a set screw; the fixed sleeve is a section of thinner steel pipe, and external threads are processed at two ends of the steel pipe; an elastic bolt and a compression spring are arranged in the central hole of the fixed sleeve; the thick end of the elastic bolt is inward, the thin end penetrates through the center holes of the compression spring and the slotted nut, and then the thin radial small hole at one end is buckled by the pull ring to form a whole small part.

7. The ball screw driven ultrahigh pressure sand control type tailless rising stem flat valve according to claim 6, which is characterized in that: the periphery of the slotted nut can be processed into a hexagonal prism or a knurled cylinder, a threaded hole with a tool withdrawal groove is processed at the inward end of the slotted nut, a radial small threaded hole is drilled on the circumferential wall of the threaded hole, a small through hole is processed at the outward end of the slotted nut, and a deep cross groove is processed on the central line of the outer end face of the small through hole.