US3814181A - Ambient pressure responsive safety valve - Google Patents

Ambient pressure responsive safety valve Download PDF

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Publication number
US3814181A
US3814181A US00319183A US31918372A US3814181A US 3814181 A US3814181 A US 3814181A US 00319183 A US00319183 A US 00319183A US 31918372 A US31918372 A US 31918372A US 3814181 A US3814181 A US 3814181A
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Prior art keywords
flow
piston
pressure
valve
urging
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US00319183A
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D Young
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Schlumberger Technology Corp
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Schlumberger Technology Corp
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Priority to US00319183A priority Critical patent/US3814181A/en
Priority to GB5901673A priority patent/GB1451510A/en
Priority to DE2364328A priority patent/DE2364328A1/de
Priority to FR7346726A priority patent/FR2212483B1/fr
Priority to CA189,098A priority patent/CA994669A/en
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Publication of US3814181A publication Critical patent/US3814181A/en
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B34/00—Valve arrangements for boreholes or wells
    • E21B34/06—Valve arrangements for boreholes or wells in wells
    • E21B34/08—Valve arrangements for boreholes or wells in wells responsive to flow or pressure of the fluid obtained
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7754—Line flow effect assisted
    • Y10T137/7756—Reactor surface separated from flow by apertured partition
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7781—With separate connected fluid reactor surface

Definitions

  • ABSTRACT A safety valve apparatus for wells producing well fluid by formation pressure and including a valve mechanism that is normally maintained in the open or flowing position by an urging means and is closed responsive to a predetermined differential pressure developed between flowing pressure, within the valve apparatus and ambient pressure, externally of the valve apparatus.
  • a predetermined differential pressure develops a force overcoming the bias of the urging means and moves the valve mechanism to the closed position thereof.
  • the valve apparatus is provided with means for modifying the effective size of the inlet orifice of the valve mechanism responsive to a predetermined decrease in ambient pressure from a normal operating range, thereby developing the predetermined pressure differential for achieving automatic closure of the safety valve apparatus.
  • This invention relates generally to safety valve apparatus for downhole environment in wells having a formation pressure for producing well fluid, and more specifically concerns the provision of a safety valve apparatus adapted for positive closure of a safety valve mechanism in the event ambient pressure at the level of the safety valve should decrease below a predetermined minimum.
  • Explosions both at surface flow control equipment and within the well bore below the surface equipment, may result in sufficient damage to allow a'particular well to blow wild.
  • Wells may also blow-out due to shifting of earth stratum through which the well bore passes and likewise, may blow-out due to insufficient structural interconnection between well cement within the well bore and the earth stratum through which the well bore passes,
  • Subsurface production flow control apparatus may be capable of preventing explosion and fires that otherwise might occur in the event of damage or malfunction that surface flow control systems.
  • subsurface flow control safety equipment may effectively prevent the pollution of the surface environment tha might otherwise occur if an offshore well is allowed to blow wild. Since subsurface safety valve mechanisms may effectively present a great majority of well blow-outs and since pollution control is so extremely important from the standpoint of conservation, it is obvious that subsurface safety mechanisms are necessary to efficient functioning of the petroleum industry.
  • Surface and subsurface safety valve equipment may be developed that effectively achieves shut-in of surface or subsurface production flow control equipment to terminate the flow of production fluid in the event excessive well pressures should develop and in the event the flow control equipment may be subjected to excessive flow of production fluid.
  • presently available downhole safety valve equipment is solely velocity sensitive and remains open to allow the flow of production fluid during periods of normal or low velocity flow. Such valves are typically actuated by forces developed during high velocity flow to move the valve structure to the closed position and stop the flow of production fluid.
  • One typical device for serving this purpose is a so-called velocity sensitive valve that includes a spring operator piston which is sealingly slidable within a housing and carries a flow restriction, typically referred to as a flow bean, through which the flowing well fl-uid passes.
  • the pressure drop across the restriction of the flow bean acts on an area defined generally by the piston seal diameter and the bore diameter of the flow restriction to produce an upward resultant force that is related to the flow rate or velocity.
  • the valve closes to shut off the flow.
  • valve element is a poppet valve device that includes an enlarged head around which the flowing fluid passes immediately before it flows through lateral ports in the valve actuator sleeve. ln'the closed position, the head engages an annular valve seat with a metalto-metal seal.
  • This type of closure presents a number of difficulties, however. It is likely to leak where there are small manufacturing imperfections in the respective seal surfaces. Abrasives such as sand grains in the well fluids, scale and the like, tends to erode away the metal seat and cause a tiny leak which, in very short order, may be enlarged by cavitation and result in the failure of the valve.
  • valve element does not movedirectly into a tight sealing position and is allowed to oscillate or to develop a throttling function for any period of time before closing, the throttling condition will likely result in cavitation of the sealing parts, thereby rendering the valve inoperative.
  • Another commonly employed valve system utilizes a vall valve element, where closure is effected by metalto-metal contact between the ball and a companion seat or by a bonded seal ring that seats against the metal surface of the ball.
  • a condition of throttling can occur if the valve ball is not moved directly and firmly to its fully closed position upon immediate sensing of If a leak should occur in the surface flow equipment of the well, and' if the leak is initially small and increases due to erosion or cavitation of the flow control equipment, the differential pressure condition that causes automatic closure in a velocity sensitive well safety system may cause a throttling condition to occur and, therefore, may cause cavitation of the safety valve mechanism, rendering the safety valve inoperable. It is, therefore, a primary object of the present invention to provide a novel safety valve mechanism that is capable of closure responsive to a predetermined pressure differential but is not subject to erosion by well fluid due to the development of a throttling condition.
  • a novel downhole safety valve mechanism for a well that is responsive to a predetermined decrease in ambient pressure in a well bore externally of a safety valve mechanism for developing a pressure drop that causes closure of the safety valve.
  • This invention also contemplatesthe provision of a novel downhole safety valve mechanism that is of inexpensive nature, is reliable in use and low in cost.
  • a downhole safety valve mechanism may include a housing structure adapted for connection to a production tubing within a well system within which housing may be disposed a safety valve assembly capable of terminating the flow of production fluid responsive to the development of an adverse pressure condition within the well.
  • a valve seat may be provided within the housing against which may be seated a valve element that is movable between open and closed positions relative to the seat.
  • the valve element may be connected to an actuating sleeve movably disposed within the housing and urged to the open position thereof by a spring element to allow flow of fluid through the valve mechanism.
  • the movable sleeve may constitute a piston against which a force is developed by differential pressure to cause closure of the valve element, the pressuredifferential being defined.
  • Sufiicient pressure differential may be developed to cause automatic closure of the safety valve mechanism responsive to a predetermined decrease in ambient pressure that causes a movable element to modify the effective size of the inlet opening of the valve mechanism in direct proportion to the amount of decrease in ambient pressure.
  • a plunger carried by a pressure dome portion of the valve housing, and movable responsive to pressure differential developed between ambient pressure and pressure within a variable volume gas charged chamber, functions to restrict the effective size of the inlet opening of the valve if excessive flow of production fluid through the valve structure, which might be caused by failure of surface equipment, decreases ambient pressure within the well bore below a predetermined minimum operating level.
  • the plunger causes a pressure differential to occur at the inlet opening of the valve assembly to which pressure differential, the actuating sleeve is responsive to move the valve element to the closed condition thereof.
  • An urging means such as a compression spring may be utilized to assist movement of the plunger element towarda position restricting the effective size of the inlet opening.
  • FIG. I is a pictorial representation, illustrated partially in section, of a subsurface earth formation having a well bore extended therethrough and being lined with a well casing enclosing a production tubing, to which production tubing is attached a downhole safety valve mechanism constructed in accordance with the present invention.
  • FIGS. 2A, 2B and 2C are longitudinal sectional views forming the upper intermediate and lower portions, respectively, of a safety valve mechanism constructed in accordance with the present invention.
  • FIG. 3A is an enlarged cross-sectional view of the valve seal assembly of the safety valve mechanism of the present invention.
  • FIG. 3B is an enlarged cross-sectional view of an ambient pressure responsive valve inlet opening controller constructed in accordance with the present invention.
  • FIG. '1 an earth formation is illustrated generally at having a well bore 12 drilled therein which bore is lined with a well conduit 14 that may be cemented in place in conventional manner and traverses the earth formation being produced.
  • a production string of tubing 16 extends from the surface downwardly through a typical production packer 18 having a packing element 20 that seals off the production interval from the well casing thereabove.
  • Well fluid enters the casing 14 through perforations (not shown) disposed below the packer l8 and passes upwardly through the tubing string 16.
  • a safety valve 22 constructed in accordance with the present invention, is shown to be attached to the lower extremity of a conventional wire line setting a retrieving mandrel 24 that is seated in a landing nipple 26.
  • the retrieving mandrel 24 is provided with locking dogs 28 and locator keys 30, disposed on either side of seal packing rings 32, and the upper extremity of the mandrel 24 is provided with a running and retrieving neck 34.
  • the details of construction of the setting mandrel assembly, as well as the procedures for running and retrieving the assembly on wire line, are well known to those skilled in the art and form no part of the present invention.
  • FIGS. 2A, 2B and 2C depict the upper, intermediate and lower portions, re-
  • a valve housing may comprise an upper sub 38 having an internally threaded upper extremity 40 for establishing threaded connection with the lower extremity of the setting mandrel 24.
  • the housing 36 may be defined by separate upper and lower sections 42 and 44, respectively, that are joined by a coupling 46 having an intermediate thickened wall section defining abutments 48 and 50 for engagement by the upper and lower housing sections 42 and 44 respectively.
  • the coupling 46 may be also provided with upper and lower externally threaded portions 52 and 54, respectively, adapted to receive the internal threads of the upper and lower housing sections.
  • the housing 36 of the safety valve may also be provided with a valve section 56, provided with internal threads 58 at the upper extremity thereof for threaded connection to a lower externally threaded portion 60 of the lower housing section 44.
  • the valve section may also be provided with internal threads 62 at the lower extremity thereof for connection to the upper externally threaded portion 64 ofa support coupling 66.
  • the lower extremity of the lower housing section 44 may define an annular abutment 68 providing support for a seat element 70 that is retained in engagement with the abutment surface 68 by an annular seat support flange 72 defined within the valve section 56 of the housing.
  • the seat element 70 may be provided with a sealing element 74, such as an O-ring or the like, retained within a circumferential groove for establishment for a sealed relationship between the seat element 70 and the internal wall 76 of the seal pocket defined between the abutment shoulder 68 and the internal fiange 72.
  • the seat ring 70 presents an inclined stop surface 78 located just above an inwardly facing sea] surface 80.
  • a valve element may be disposed for reciprocation within the valve section 56 of the housing and may include a tubular portion 84 provided with an upper threaded extremity 86 for threaded connection to a lower internally threaded portion 88 of a valve actuating sleeve element 90, also disposed for reciprocation within the housing 36.
  • the tubular portion 84 of the valve element may be provided with a closed lower extremity 92 which may be stepped down to define an annular abutment portion 94 providing support for an annular seal retainer ring 96.
  • a sea] support end cap 98 may be provided with internal threads 100 for threaded connection with external threads 102 of the valve element, and together with the retainer ring 96 may serve to retain an annular sealing element 104 that may be compressed to some degree by the retainer ring or compression ring 96 to increase the degree of sealing engagement between the sealing element 104 and the seal surface 80, when the valve element is in its closed position.
  • the outer periphery of the sealing element 104 will slide into sealing engagement with the generally cylindrical sealing surface 80 of the seal element 70 and a tapered surface 106 of the compression ring 96 ,will move into abutment with the tapered sur face 78 of the seat element.
  • the compression ring 96 will be forced away from the abutment portion 94 and will deform the sealing element 104, thereby causing the sealing element to increase the pressure of its sealing contact with the annular sealing surface 80.
  • the sealing ability of the valve is therefore increased directly proportional to increase in pressure differential across the closed valve.
  • fluid being produced through the safety valve mechanism will flow around the lower extremity of the valve element and will enter the tubular portion 84 through at least one and preferably a plurality of apertures 108.
  • the production fluid will then continue upwardly through a flow passage 110 defined by cooperating tubular portions of the valve element and valve actuating sleeve and into the tubing string to which the safety valve mechanism is connected by the upper sub 38.
  • valve element 82 It will be desirable to provide a mechanism for retaining the valve element 82 in the open or H6. 28 position thereof as long as ambient pressure within the well casing and externally of the safety valve mechanism is within a proper operating range and to achieve closure of the valve element to stop the flow of production fluid in the event ambient pressure should fall below a pre determined minimum level for any reason whatever.
  • Means for achieving pressure responsive control on the valve element 82 may conveniently take the form illustrated in FIG. 2A where an urging means, such as a compression spring 112 may be interposed between abutment shoulders 114 and 116 defined respectively by the lower extremities of the coupling 46 and by a thickened wall portion 120 of the valve actuating sleeve element 90.
  • the compression spring 112 under normal conditions, will urge the valve actuating sleeve element 90 downwardly until an annular tapered shoulder 122, defined thereon, moves into abutment with a tapered support shoulder 124, defined internally of the lower housing section 44 where further downward movement of the valve element 82 will be restrained by the stop surface 124.
  • annular sealing element 126 may be retained within an annular groove defined within an inwardly projecting portion 128 of the coupling element 46, which sealing element may establish sealing contact with a generally cylindrical sealing surface 130 defined on the valve actuating sleeve 90.
  • a second annular sealing element 32 may be retained within an annular groove defined in a piston element 134 having a lower internally threaded extremity 136.
  • the sealing element 132 may be disposed in sealing engagement with an internal sealing surface 140 defined within the upper housing section 42.
  • the piston element 134 cooperate with the upper housing section 42, the coupling element 46 and sealing element 126 to define a valve actuating chamber 142 that is communicated with ambient pressure by at least one and preferably a plurality of orifices 144 formed in the upper housing section 42.
  • piston element 134 may be provided a thin walled sleeve cooperating with a sleeve 137 depending from the upper sub 38 to define a barrier for sand and other abrasive matter produced along with the well fluid.
  • the sleeves 135 and 137 define a dead space therebetween that prevents sand from accumulating above the O-ring seal 132, thereby protecting the seal from abrasive wear.
  • Ambient pressure communicated through orifices 144 into the annular valve actuating chamber 142, will act upon'a surface area of the valve actuating sleeve element 90 defined by the piston element 134, and referred to as area Al, while fluid pressure within the valve housing downstream of the valve element, also referred to as flowing pressure, acts upon a surface area of the valve actuating sleeve referred to as A2.
  • area Al fluid pressure within the valve housing downstream of the valve element
  • flowing pressure acts upon a surface area of the valve actuating sleeve referred to as A2.
  • ambient pressure acting upwardly upon the sleeve 90 will be slightly overbalanced by flowing pressure acting downwardly upon the sleeve and the net downward pressure responsive force will be added to the downward force developed by the compression spring 112, thereby maintaining the sleeve, and the valve element connected thereto, in the lowermost or open position thereof.
  • the differential pressure acting upon the sleeve 90 will be such that a resultant force of substantial magnitude will be developed acting upwardly upon the sleeve 90 through the piston element 134 that overcomes the compression of spring 112 and urges the valve actuating sleeve 90 to the upper position thereof, thereby causing the valve element 82 to seat against the seat element 70 and stop the flow of fluid through the apertures 108.
  • the pressure of flowing means for achieving valve closure may conveniently take the form illustrated particularly in FIG. 2C where a combination inlet adapter and support sleeve 146 is shown to be provided with upper and lower internally threaded extremities 148 and 150, respectively, for connection to externally threaded portions 152 of coupling element 66 and 154 of a coupling element 156.
  • the coupling element 156 may be provided with an externally threaded lower portion 158 adapted to receive internal threads 160 defined within the upper extremity of a pressure dome housing 162.
  • the housing 162 may be closed at its lower extremity by a closure plug 164 having an externally threaded portion 166 disposed in threadedconnection with the lower internally threaded portion 168 of the housing 162.
  • the closure plug 164 cooperates with the housing 162 and coupling element 156 to define an internal pressure chamber or dome, within which may be introduced a gaseous medium at any suitable pressure, depending upon the desired operational characteristics of the safety valve mechanism.
  • the closure plug 164 may be manufactured to define a gas inlet passage 172 communicated with a closure bore 174 and an internally threaded gas supply connector receptacle 176.
  • the closure bore 174 may have an internally threaded outer extremity 178 for threaded connection of a closure element 180 within the bore 174.
  • Within an annular groove defined at the upper extremity of enclosure element 180 may be disposed a sealing element 186 that may be urged into sealed engagement with a frusto-conical sealing surface 188 defined about the inlet passage 172.
  • the closure element 180 When it is desired to introduce pressurized gaseous medium into the pressure chamber 170, the closure element 180 may be unthreaded sufficiently to move the sealing element 186 away from the sealing surface 188 and allow communication between the passage 172 and the gas supply receptacle 176.
  • the gas supply conduit may be threadedly connected to receptacle 176 and gas may be introduced through the passage 172 until the pressure chamber 170 has reached an operating pressure.
  • the closure element 180 then may be threaded fully into the bore 174, thereby urging the seal element 186 into tight sealing engagement against the sealing surface 188.
  • the gas supply conduit may be unthreaded from the threaded receptacle 176 and, if desired, the receptacle may be suitably plugged.
  • the upper extremity of the coupling 156 may be provided with a plunger bore 190 through which a generally cylindrical portion 192 of a plunger element 194 may extend.
  • An annular sealing element 196 such as an O-ring or the like, may be retained within an annular groove 197 defined within the bore 190 and may establish sealing engagement with the cylindrical surface 198 defined by the cylindrical portion of the plunger.
  • An annular rigid seal carrier 200 may be retained in fixed relation to the housing 162 by an inwardly extending shoulder 202 defined at the lower extremity of the coupling 156 and may be sealed relative to the housing by an annular sealing element 204 retained within an external groove defined in the seal carrier.
  • sealing element 206 may be retained within an internal annular seal groove defined in the seal carrier and may establish sealing engagement with the cylindrical surface 198 of the plunger 194.
  • the seal carrier 200, the sealing element 196, the coupling 156 and the seal ring 196 cooperate to define sealed passages through which the plunger 194 may extend.
  • the bores through the seal carrier and coupling also serve effectively as guiding surfaces to maintain alignment of the plunger with the inlet aperture 112 during linear movement thereof.
  • a mechanical force such as might be developed by a compression spring 208 or any other suitable urging means to develop a resultant force tending to urge an enlarged head portion 210 of the plunger into restricting relation with an inlet aperture 212 in the coupling element 66 to restrict the flow of production fluid through the coupling passage 114 and into the safety valve mechanism.
  • the combined forces of gas pressure and the spring force acting upon the plunger, during normal operation of the safety valve mechanism, are overcome by a resultant downward force, acting upon the plunger, that is developed by ambient pressure and maintains the plunger in its FIG. 2C position thereof until ambient pressure decreases below a predetermined minimum level.
  • the pressurized medium within the pressure chamber or dome 170 is always maintained at a lower pressure than the ambient pressure expected during normal operation of the flow system of the well and the combined forces developed by the gas eous medium within the pressure chamber and the force developed by the compression spring will be less than the downward force developed by ambient pressure during normal valve operation.
  • the pressure of the compressible medium in the pressure dome may be designated P while the pressure of production fluid flowing through the safety valve mechanism may be P;
  • the force exerted by the compression spring in the pressure dome may be P and ambient pressure may be designated P
  • P P During normal operation of the flow system of the well P P is less than P and, therefore, the plunger will be retained in its lowermost position by the resultant force acting on the plunger and the inlet aperture 212 will be unrestricted.
  • P will be less than P and the valve actuating mechanism will be maintained in the open position thereof by the resultant force created by pressure differential between P; and P,,.
  • the compression spring 112 will develop a force acting downwardly upon the annular shoulder 116 of the valve actuating sleeve and will overbalance a force developed by ambient pressure within the valve actuating chamber 142 acting upwardly upon the piston portion 134 of the sleeve element, thereby resulting in a net downward force which maintains the sleeve in its lowermost position against the tapered stop shoulder 124. Under this condition the valve element will be open and production fluid will be produced in unrestricted manner through the safety'valve mechanism and the tubing string. The flow of production fluid will be controlled elsewhere in the flow system, such as by a choke disposed in the surface flow control equipment.
  • Ambient pressure will act upon the plunger 194 and will develop a force that overbalances the combined forces developed by pressurized medium within the pressure chamber 170 and by the compression spring 208, thereby developing a net downward force maintaining the support shoulder 211 in engagement with the upper portion of the coupling 156.
  • ambient pressure should decrease below a predetermined minimum operating level the head portion 210 of the plunger will be caused to move into juxtaposed relation with the inlet aperture 212, thereby developing a severe pressure drop across the inlet aperture 212.
  • This condition causes a severe pressure differential to exist across the piston element 134, due to ambient pressure within the valve actuating chamber 142 acting upwardly on the piston which develops a force of sufficient magnitude to overcome the compression force of spring 112, and thereby urges the valve actuating sleeve 90 upwardly and moves the valve element 82 to its closed position as shown in FIGS. 4A and 4B.
  • valve element 82 moves to its closed position and the sealing element 104 achieves sealing engagement with the sealing surface of the valve seat element 70, flow of production fluidthrough the valve will be stopped and the valve element will remain closed due to the pressure differential acting upon the piston portion-134 of the valve actuating sleeve 90.
  • pressure within the inlet passage 114 upstream of the valve element will quickly become balanced with ambient pressure.
  • the valve element 82 has sealed the low pressure condition from the inlet passage, the reduced pressure condition will no longer be reflected below the safety valve. Ambient pressure within the well, therefore, will suddenly increase to the maximum well pressure and the increased ambient pressure, acting upon the plunger 194, will again develop a net downward force that will urge the plunger to the lowermost position thereof.
  • a pressurized medium may be injected into the tubing string above or downstream of the valve and, acting upon surface area A2 will develop a force which, when added to the force developed by compression spring 112, will overcome the force developed by ambient pressure acting on area A1 of the piston.
  • a downward resultant force is thereby produced that will move the actuating sleeve and the valve element to the open position thereof, as shown in FIG. 2A.
  • ambient pressure will be at its highest level and production flow may be initiated simply by bleeding off the injected pressure, such as by opening ofa surface flow control valve of the well production system.
  • the safety valve mechanism of this invention provides a valve mechanism that will remain open, allowing normal unrestricted flow of production fluid as long as ambient pressure within the well remains within a predetermined operating range.
  • a mechanism is provided for closure of the safety valve assembly responsive to development of a predetermined decrease in ambient pressure and means is also provided for developing a pressure differential capable of actuating the valve assembly to-its closed position responsive to decrease in ambient pressure below a predetermined minimum pressure level.
  • the valve actuating sleeve and valve assembly of the present invention will be maintained in a static position and will not be allowed to reciprocate as is typically the case where a safety valve mechanism is maintained in its open position by force developed solely by pressure differential across a restriction provided in the flow path through the valve mechanism.
  • valve assembly After becoming automatically closed responsive to predetermined decrease in ambient pressure, the valve assembly may be reopened and placed back in production by simple injection of pressure into the tubing string above the valve.
  • the valve closes automatically, responsive to decrease in ambient pressure below a predetermined operating level, the valve may be effectively tested simply by opening a surface control valve sufficiently to increase production flow and thereby reflect a predetermined decrease in pressure into the well casing.
  • the valve will shut in as soon as ambient pressure decreases to a level allowing the plunger 194 to be urged, by the combined forces of the compression spring 208 and the fluid pressure within the pressure chamber 170, into restricting relation with the inlet aperture 112. If, during inspection or testing, the valve mechanism is found to be in need of servicing, the valve mechanism may be removed from the flow control system of the well without necessitating removal of the tubing string.
  • a conventional wire line tool may be utilized to retrieve and replace the safety valve mechanism.
  • a safety valve apparatus comprising:
  • valve means being supported by a well tubing and including co-engageable means being movable between open and closed positions responsive to a pressure differential of a predetermined magnitude;
  • flow restriction means being disposed upstream of said valve means and being responsive to a decrease in ambient pressure in the well bore for developing said pressure differential.
  • said flow restriction means includes a movable ele ment that restricts the flow of production fluid toward said valve element.
  • a safety valve apparatus as recited in claim 1, wherein:
  • said valve means includes an inlet opening
  • said developing means comprises a piston having a force due to said ambient pressure applied to one side thereof and a substantially constant preselected opposing force applied to the other side thereof.
  • said piston defines a plunger cooperating with said inlet opening to restrict the size of said opening responsive to said decrease in ambient pressure.
  • a safety valve apparatus adapted to be positioned within a well casing of a well having formation pressure comprising:
  • valve housing means adapted for connection to the production tubing of said well, said housing means having inlet and outlet aperture means communieating said valve housing respectively with said casing and said production tubing;
  • valve means disposed within a said housing means and being movable relative to said seat means for paratus;
  • valve actuator piston means being disposed in movable relation to said housing means and being movable relative to said valve housing responsive to predetermined pressure differential between ambient pressure and pressure within said valve housing means, said valve actuator means, upon being moved, inducing opening and closing movement to said valve means;
  • flow restricting means being supported within said well casing upstream of said valve means and being responsive to ambient pressure for controlling the flow of production fluid toward said valve means, said flow restricting means developing said predetermined pressure differential responsive to predetermined decrease in ambient pressure.
  • said developing means comprises:
  • piston means movable supported by said valve housing means and being movable between a position allowing unrestricted flow of fluid through said inlet aperture means and positions restricting the flow of fluid through said inlet aperture means; means urging said piston means toward said positions restricting the flow of fluid through said inlet aperture means; and ambient pressure acting upon said piston means and developing a force opposing said urging means and maintaining said piston means in the said position allowing unrestricted flow of fluid.
  • said housing defining a piston actuating chamber, said piston means being disposed in sealed relation relative to said piston actuating chamber;
  • a safety valve apparatus as recited in claim 5:
  • a safety valve apparatus as recited in claim 8:
  • said means urging said piston toward said restricting position comprising a compression spring interposed between said housing means and said piston.
  • a safety valve apparatus as recited in claim 8 :
  • said means urging said piston toward said restricting position comprising a compressible medium disposed within said pressure dome and acting upon said piston, said compressible medium being normally of lower pressure than the normal operating range of said ambient pressure.
  • a safety valve apparatus as recited in claim 8 :
  • a compression spring disposed within said pressure dome and supplementing the urging force applied to said plunger by said compressible medium.
  • a safety valve apparatus comprising:
  • housing means adapted for connection to the production tubing of a well having formation pressure for producing the well, said housing means deflning.
  • valve means movably disposed within said housing and being movable between open and closed positions relative to said seat means for controlling the flow of fluid through said flow passage means;
  • piston means being carried by said valve means and being movable within said housing responsive to predetermined pressure differential between ambient pressure and pressure downstream of said valve means for moving said valve means to the closed position thereof against the bias of said urging means;
  • flow restricting means being supported within said casing upstream of said valve means and being responsive to ambient pressure for controlling the flow of production fluid toward said valve means, said flow restricting means developing said pressure differential responsive to a predetermined decrease in ambient pressure.
  • said flow restricting means being a movable element carried by said housing means and being movable between a position allowing full flow of production fluid through said inlet aperture and positions restricting the flow of production fluid through said inlet aperture;
  • said moving means comprising first and second urging means acting in combination
  • said ambient pressure normally developing a force acting on said movable element overcoming both of said urging means and retaining said movable element in said position allowing full flow of production fluid.
  • said housing defining a piston carrier section
  • a piston carried by said piston carrier section and being movable between a position allowing unrestricted flow of production fluid through said inlet aperture means and positions restricting flow of production fluid through said inlet aperture, movement of said piston being controlled by force differential responsive to predetermined decrease in ambient pressure.
  • said force differential acting upon said piston being defined by mechanically created force urging said piston toward said positions restricting flow of pro duction fluid and a force created by ambient pressure acting upon said plunger and urging said plunger toward said position allowing unrestricted flow of production fluid.
  • said force differential acting upon said plunger being defined by a mechanically created force and a force defined by static pressure acting together upon said piston and urging said plunger toward said positions restricting the flow of production fluid and a force created by ambient pressure acting upon said plunger and urging said plunger toward said position allowing unrestricted flow of production fluid.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Safety Valves (AREA)
US00319183A 1972-12-29 1972-12-29 Ambient pressure responsive safety valve Expired - Lifetime US3814181A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US00319183A US3814181A (en) 1972-12-29 1972-12-29 Ambient pressure responsive safety valve
GB5901673A GB1451510A (en) 1972-12-29 1973-12-20 Ambient pressure responsive safety valve
DE2364328A DE2364328A1 (de) 1972-12-29 1973-12-22 Sicherheitsventilanordnung fuer ein foerderbohrloch
FR7346726A FR2212483B1 (de) 1972-12-29 1973-12-28
CA189,098A CA994669A (en) 1972-12-29 1973-12-28 Ambient pressure responsive safety valve

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US00319183A US3814181A (en) 1972-12-29 1972-12-29 Ambient pressure responsive safety valve

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US3814181A true US3814181A (en) 1974-06-04

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US (1) US3814181A (de)
CA (1) CA994669A (de)
DE (1) DE2364328A1 (de)
FR (1) FR2212483B1 (de)
GB (1) GB1451510A (de)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3889751A (en) * 1974-02-01 1975-06-17 Exxon Production Research Co Subsurface safety valve
EP0190864A2 (de) * 1985-02-08 1986-08-13 Halliburton Company Druckbetätigtes Werkzeug im Bohrloch
EP0205250A1 (de) * 1985-05-03 1986-12-17 Develco, Inc. Unterirdische Betätigungsvorrichtung
EP0216970A1 (de) * 1985-09-19 1987-04-08 AVA International Corporation Ventile
US4664195A (en) * 1986-01-31 1987-05-12 Otis Engineering Corporation Safety valve
US4878053A (en) * 1985-05-03 1989-10-31 Develco, Inc. Actuation method
US20030178198A1 (en) * 2000-12-05 2003-09-25 Dewayne Turner Washpipeless isolation strings and methods for isolation
US6631767B2 (en) * 1998-11-17 2003-10-14 Schlumberger Technology Corporation Method and apparatus for selective injection or flow control with through-tubing operation capacity
EP1359289A1 (de) * 2002-03-01 2003-11-05 Shell Internationale Researchmaatschappij B.V. Sicherheitsventil im Bohrlock
US20030221839A1 (en) * 1998-08-21 2003-12-04 Dewayne Turner Double-pin radial flow valve
US20040106592A1 (en) * 2002-11-15 2004-06-03 Vicente Maria Da Graca Henriques Chelation of charged and uncharged molecules with porphyrin-based compounds
US20040244976A1 (en) * 1998-08-21 2004-12-09 Dewayne Turner System and method for downhole operation using pressure activated valve and sliding sleeve
US6892816B2 (en) * 1998-11-17 2005-05-17 Schlumberger Technology Corporation Method and apparatus for selective injection or flow control with through-tubing operation capacity
GB2418687A (en) * 2004-10-01 2006-04-05 Weatherford Lamb Pressure actuated tubing safety valve
WO2006069247A2 (en) 2004-12-22 2006-06-29 Bj Services Company Method and apparatus for fluid bypass of a well tool
WO2006069372A2 (en) 2004-12-22 2006-06-29 Bj Services Company Method and apparatus to hydraulically bypass a well tool
US20070034377A1 (en) * 2005-07-22 2007-02-15 Moyes Peter B Downhole non-return valve and method
US7201232B2 (en) 1998-08-21 2007-04-10 Bj Services Company Washpipeless isolation strings and methods for isolation with object holding service tool
USRE40648E1 (en) * 1998-08-21 2009-03-10 Bj Services Company, U.S.A. System and method for downhole operation using pressure activated valve and sliding sleeve
US20090266555A1 (en) * 2008-04-23 2009-10-29 Schlumberger Technology Corporation System and method for controlling flow in a wellbore
CN101798913A (zh) * 2010-03-10 2010-08-11 中国石油天然气股份有限公司 一种压差式井下节流器
CN103541698A (zh) * 2012-07-12 2014-01-29 中国石油天然气股份有限公司 气井井下定产量节流生产装置
CN106677747A (zh) * 2017-01-19 2017-05-17 长江大学 一种水平井完井防砂用充填式控水筛管
CN109057749A (zh) * 2018-07-30 2018-12-21 中国石油天然气股份有限公司 一种易打捞卡瓦式井下节流器
US10920529B2 (en) 2018-12-13 2021-02-16 Tejas Research & Engineering, Llc Surface controlled wireline retrievable safety valve

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* Cited by examiner, † Cited by third party
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US4721162A (en) * 1984-08-29 1988-01-26 Camco, Incorporated Fluid level controlled safety valve

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US3045759A (en) * 1955-01-26 1962-07-24 Udell Inc Well apparatus
US3050132A (en) * 1957-07-01 1962-08-21 Page Oil Tools Inc Fluid pressure operated shut-off valve for wells
US3065794A (en) * 1957-08-19 1962-11-27 Page Oil Tools Inc Retrievable well flow control valve

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Publication number Priority date Publication date Assignee Title
US3045759A (en) * 1955-01-26 1962-07-24 Udell Inc Well apparatus
US3050132A (en) * 1957-07-01 1962-08-21 Page Oil Tools Inc Fluid pressure operated shut-off valve for wells
US3065794A (en) * 1957-08-19 1962-11-27 Page Oil Tools Inc Retrievable well flow control valve

Cited By (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3889751A (en) * 1974-02-01 1975-06-17 Exxon Production Research Co Subsurface safety valve
EP0190864A3 (en) * 1985-02-08 1988-09-21 Halliburton Company Pressure-responsive downhole well tool
EP0190864A2 (de) * 1985-02-08 1986-08-13 Halliburton Company Druckbetätigtes Werkzeug im Bohrloch
US4618000A (en) * 1985-02-08 1986-10-21 Halliburton Company Pump open safety valve and method of use
EP0205250A1 (de) * 1985-05-03 1986-12-17 Develco, Inc. Unterirdische Betätigungsvorrichtung
US4736791A (en) * 1985-05-03 1988-04-12 Develco, Inc. Subsurface device actuator requiring minimum power
US4878053A (en) * 1985-05-03 1989-10-31 Develco, Inc. Actuation method
EP0216970A1 (de) * 1985-09-19 1987-04-08 AVA International Corporation Ventile
US4664195A (en) * 1986-01-31 1987-05-12 Otis Engineering Corporation Safety valve
USRE40648E1 (en) * 1998-08-21 2009-03-10 Bj Services Company, U.S.A. System and method for downhole operation using pressure activated valve and sliding sleeve
US7152678B2 (en) * 1998-08-21 2006-12-26 Bj Services Company, U.S.A. System and method for downhole operation using pressure activated valve and sliding sleeve
US7198109B2 (en) * 1998-08-21 2007-04-03 Bj Services Company Double-pin radial flow valve
US20030221839A1 (en) * 1998-08-21 2003-12-04 Dewayne Turner Double-pin radial flow valve
US7201232B2 (en) 1998-08-21 2007-04-10 Bj Services Company Washpipeless isolation strings and methods for isolation with object holding service tool
US20040244976A1 (en) * 1998-08-21 2004-12-09 Dewayne Turner System and method for downhole operation using pressure activated valve and sliding sleeve
US6631767B2 (en) * 1998-11-17 2003-10-14 Schlumberger Technology Corporation Method and apparatus for selective injection or flow control with through-tubing operation capacity
US6892816B2 (en) * 1998-11-17 2005-05-17 Schlumberger Technology Corporation Method and apparatus for selective injection or flow control with through-tubing operation capacity
US7124824B2 (en) 2000-12-05 2006-10-24 Bj Services Company, U.S.A. Washpipeless isolation strings and methods for isolation
US20030178198A1 (en) * 2000-12-05 2003-09-25 Dewayne Turner Washpipeless isolation strings and methods for isolation
EP1359289A1 (de) * 2002-03-01 2003-11-05 Shell Internationale Researchmaatschappij B.V. Sicherheitsventil im Bohrlock
US20040106592A1 (en) * 2002-11-15 2004-06-03 Vicente Maria Da Graca Henriques Chelation of charged and uncharged molecules with porphyrin-based compounds
US20060157255A1 (en) * 2004-10-01 2006-07-20 Smith Roddie R Downhole safety valve
US7654333B2 (en) 2004-10-01 2010-02-02 Weatherford/Lamb, Inc. Downhole safety valve
GB2418687B (en) * 2004-10-01 2009-11-04 Weatherford Lamb Pressure actuated tubing safety valve
GB2418687A (en) * 2004-10-01 2006-04-05 Weatherford Lamb Pressure actuated tubing safety valve
US20060070744A1 (en) * 2004-10-01 2006-04-06 Weatherford/Lamb, Inc. Pressure actuated tubing safety valve
US7246668B2 (en) 2004-10-01 2007-07-24 Weatherford/Lamb, Inc. Pressure actuated tubing safety valve
WO2006069247A2 (en) 2004-12-22 2006-06-29 Bj Services Company Method and apparatus for fluid bypass of a well tool
WO2006069372A2 (en) 2004-12-22 2006-06-29 Bj Services Company Method and apparatus to hydraulically bypass a well tool
US7814982B2 (en) * 2005-07-22 2010-10-19 Baker Hughes Incorporated Downhole non-return valve and method
US20070034377A1 (en) * 2005-07-22 2007-02-15 Moyes Peter B Downhole non-return valve and method
US8002040B2 (en) 2008-04-23 2011-08-23 Schlumberger Technology Corporation System and method for controlling flow in a wellbore
US20090266555A1 (en) * 2008-04-23 2009-10-29 Schlumberger Technology Corporation System and method for controlling flow in a wellbore
CN101798913A (zh) * 2010-03-10 2010-08-11 中国石油天然气股份有限公司 一种压差式井下节流器
CN101798913B (zh) * 2010-03-10 2012-11-14 中国石油天然气股份有限公司 一种压差式井下节流器
CN103541698A (zh) * 2012-07-12 2014-01-29 中国石油天然气股份有限公司 气井井下定产量节流生产装置
CN103541698B (zh) * 2012-07-12 2016-01-20 中国石油天然气股份有限公司 气井井下定产量节流生产装置
CN106677747A (zh) * 2017-01-19 2017-05-17 长江大学 一种水平井完井防砂用充填式控水筛管
CN109057749A (zh) * 2018-07-30 2018-12-21 中国石油天然气股份有限公司 一种易打捞卡瓦式井下节流器
US10920529B2 (en) 2018-12-13 2021-02-16 Tejas Research & Engineering, Llc Surface controlled wireline retrievable safety valve

Also Published As

Publication number Publication date
FR2212483B1 (de) 1979-03-16
GB1451510A (en) 1976-10-06
DE2364328A1 (de) 1974-07-04
CA994669A (en) 1976-08-10
FR2212483A1 (de) 1974-07-26

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