US2854929A - Oil well standing valve - Google Patents

Description

Oct. 7, 1958 H. E. M GOWEN, JR., ETAL 2,854,929

O IL WELL STANDING VALVE Filed Feb. 24, 1956 f. MGowew, //1 5. f. 50/250 INVENTORS BY QQILQM' United States Patent i OIL WELL STANDING VALVE Harold E. McGowen, Houston, and Douglas E. Daflin, Pasadena, Tex., assignors to Cameo, incorporated, Houston, Ten, a corporation of Texas Application February 24, 1956, Serial No. 567,622

Claims. (Cl. 103-221) This invention relates to an improvement in standing valves of the type commonly employed at the bottom of an oil well for allowing production fluid to pass freely upwardly and for closing against undesirable back flow. Occasionally it becomes necessary to remove and check a valve assembly, and in order to avoid the need for pulling or completely removing the production pipe string from the well at such time, a special landing or anchoring nipple may be incorporated initially in the pipe string for reception of a retrievable valve assembly which can be releasably chucked on the end of a suspension wire line and lowered or run into place and then released for suspension line withdrawal, and which retrievable assembly after installation can at any time be picked up and removed with the aid of a wire line pulling tool which, after being lowered within the tubing string to the level of the valve, can be caused to grab or clutch itself to the valve unit for withdrawal thereof. Inasmuch as the retrievable assembly is tightly fitted and sealed in the landing nipple and supports the load of an upstanding column of production fluid which may be of considerable weight and height above the valve, a powerful pull on the suspension cable may be called for, wherefore the pulling stress is apt to cause undue strain on and breakage of any of the wire line, the clutching connection, the valve unit, and the production string.

An object of the present invention is to provide an improved retrievable structure operable to perform the normal function of a one-way standing valve and having a pulling tool engageable formation and connected parts which respond in the first increment of upward travel to a withdrawal force to shift a part of the valve assembly in advance of the upward bodily displacement of the nipple-landed portion of the valve assembly and which preliminary response of the shifted part uncovers a bypass around the check valve, so that the standing column of oil no longer is trapped above the valve assembly but can be displaced by flowing from one side to the other of the valve assembly and free the valve assembly from the fluid load. That load often is the major resistance to initial upward movement of the mounted valve assembly, and load removal facilitates breaking loose the valve assembly for elevation within the production string upon further upward travel of the pulling tool.

A further object of the invention is to provide a simple but rugged standing valve which will be economical to manufacture and which in effect involves only an inner hollow body to be fitted and sealed at its lower end in a landing nipple and an outer tube slidably sleeved on the upper portion of the inner tube for limited axial travel from a bottom position in which it closes a valve by-pass to a top limit position in which it suspends the inner tube with the Dy-pass open. Such limits are established by interengaging abutment surfaces on a running tool connector part constituted by a central pin axially aligned with the main flow passage through and at the upper terminal of the inner tube and on a pulling tool connectorpart constituted by the upper terminal portion strict maximum flow-volume which, because of the fairly of the outer tube and sleeved on a necked portion of the pin. The outer tube initially is located in its lower limit by-pass closing position by a releasable shear pin connection, and, among other things, the locking together of the parts maintains in alignment slot openings through both tubes in continuation of the main flow passage through the inner tube, and the size of the openings and their locked alignment insures against restriction of fluid flow as controlled by the check valve caged within the inner tube.

Another object of the invention is to provide an outer tube or by-pass control valve which is balanced with respect to fluid pressures acting thereon and which is to say that the opposite upper and lower by-pass valve sur faces exposed to the weight of the standing fluid column are of substantially equal area, so that by-pass valve travel relative to the main valve body encounters no appreciable resistance from the oil column and by opening the bypass the main valve body also is relieved from column weight and frictional resistance otherwise offered.

Additional objects and advantages will become apparent during the course of the following specification having reference to the accompanying drawing illustrating in vertical section the detail structure and installation of a preferred embodiment of the improved valve arrangement.

Referring to the drawings, a fragment of a production string is shown at 1 as incorporating near its lower end a special landing nipple 2 whose inside diameter is stepped to afford an upwardly facing annular landing seat or shoulder 3 between an upper portion of larger inside diameter approximating that of the tubing string thereabove and a lower portion of slightly smaller inside diameter and whose interior surface is accurately machined and polished to close tolerance for a snug or press fit with a correspondingly finished mating surface of the valve body to be located within the landing nipple. The nipple 2 is screwed, welded or otherwise coupled in end to end succession with the usual joint components of the tubing string and forms a part thereof.

The valve assembly illustrated consists essentially of an inner tubular body for seating a check valve against back flow in the passage through the body and for mounting at its lower end in the landing nipple 2 and an outer sleeve valve member slidably sleeved on the upper portion of the tubular body for limited upward travel from an initially fixed position in which the slider sleeve valve closes a by-pass around the check valve. For conven ience of manufacture and assembly, the inner or main valve body involves a number of separately formed parts secured, as by screw threads, in end to end succession. As shown, there is an intermediate tubular part 4 having opposite end portions externally shouldered and reduced in diameter and respectively threaded into a rounded nosed bottom piece or packing ring retaining nut 5 and an upper domed piece or valve retaining cage 6. Clamped within an internal annular pocket between co-operating abutments on the valve cage 6 and the upper end of the tubular member 4 is an external annular rib of a renewable valve seating ring 7, which may be of hardened metal and provides an upwardly facing seat for a downwardly closing ball check 3. Above the ring seat 7, the doomed cage 6 is of an inside diameter to provide an abundance of free flow clearance around the ball valve 8, and the domed cage has in its upper and side walls one or more openings or flow passages therethrough communicating the valve cage with the production tubing above the valve unit. Three of such openings 9 equally spaced apart circumferentially may be milled or otherwise formed, and their combined flow capacity should be equal to or greater than the flow clearance around the ball valve so as not to relarge size of the central passage through the assembly and the free clearance in the cage around the ball, is intendedly quite large. Centrally of the upper end wall of the cage .6 is a screw threaded socket to receive the lower'end of an upstanding terminal pin it affording a connecting neck below the larger diameter head or conical tip 11 which is for detachable connection with a running in or lowering tool by which the valve unit is suspended while it is being dropped downwardly in the tubing string and landed in the locating nipple.

For seal anchorage in the landing nipple, the tubular body 4 is of stepped outside diameter to provide an intermediate downwardly facing landing shoulder 12, and the outside diameter of the body portion below the shoulder as well as of the nose piece 5 approximates or is only slightly smaller than the inside diameter of the nipple below the landing seat 3 for a close frictional fit, both to resist accidental displacement and leakage of fluid. Immediately below the lowermost shoulder and surrounding the reduced end portion of the body 4 are located a stack of V-type packing rings 13 held in place by the end nut or nose piece 5 for co-operation with the interior surface of the nipple 2 and with the ball check valve 3 in completing the seal against back flow of the upstanding fluid column within the production string above the valve assembly.

Upwardly from the landing seat 12, the larger diameter portion of the valve body is somewhat smaller than the inside diameter of the adjoining portions of the nipple and tubing string and provides clearance passage there between, and in this region between the-landing seat and the ball valve the wall of the tubular body 4 has one or more radially extending ports 14 drilled therethrough to communicate the annular clearance space with the central passage in the body below the valve as a secondary flow passage or bypass around the one-way seated valve. Initially the bypass 14 is covered and sealed by the outer valve or slide sleeve 15 surrounding and closely fitted to the upper portion of the inner valve body in overlapping relation with the by-pass, and additionally by a pair of sealing O-rings 16 carried in annular grooves above and below the by-pass 14 in bearing engagement with the interior surface of the sleeve 15.

To uncover the overlapped ports 14, the sleeve must be telescoped upwardly on the main valve body. To that end, its upper portion terminates in an inwardly extending wall or cap overlying the similar end wall of the domed cage 6 and from which extends upwardly a tubular sleeve 17 slidably embracing the headed pin and having a headed tip IS. The length of the sleeve i7 is less than that of the pin 10, and the uppermost face of the domed cage 6 and the underside of the pin head 11 afford abutment seats for opposite ends of the sleeve 17 in defining the range of relative slide travel of the outer sleeve member 15. That portion of the inwardly extending upper wall of the outer sleeve which overlies the domed cage is provided with openings or passages 19 similar to and in aligned co-operation with the openings 9. For maintaining the openings 9 and 19 in alignment and for releasably retaining the by-pass sleeve against accidental upward travel to bypass open position, the inner and outer valve members should be detachably connected against relative movement, as by means of a replaceable shear pin 20 through aligned openings drilled through the head 18 and the pin it), with the sleeve positioned at its lower limit.

With the parts constructed as thus described, a lowering wire line tool can be engaged with the terminal head 11 for lowering the parts down into final position. When the valve assembly is to be removed, a pulling tool suspended on a wire line will be caused to overshoot the head 11 and engage with the head 18 of the outer member. When so engaged, an upward force resisted by the close frictional lit of the body in the nipple and the fluid column load on the seated ball valve, will break the, shear pin 20,

4 and raise the outer member for the short distance within the limit between the heads 18 and 11 and thus move the bottom of the sleeve 15 upwardly above the by-pass 14. In this connection, it is to be noted that the upper and lower surfaces of the outer member are so constructed as to be of substantially equal area, and thus the valve is balanced as respects the leader? the standing fluid column, and its upward travel does not have to be against the resistance of any of the fluid load. Uncovering of the ports opens a passageway around the exterior of the body and through the wall into the passage below the valve and thereby renders ineffective the normal action of the check valve, and more particularly it provides for a balance of pressures on the top and bottom surfaces of the entire valve assembly, so that further upward pull of the wire line is not resisted by the fluid column weight, and facilitates the upward displacement of the valve body without strain that might otherwise be imposed on the parts by the need for lifting the fluid column for that initial increment of movement necessary to free the valve assembly from the landing nipple.

While the foregoing description has been specific to the particular embodiment of the invention as illustrated, it is to be understood that modifications may be made as come Within the scope of the appended claims.

What is claimed is:

l. A standing valve for retrievable mounting in a well production string, including a body having a passage therethrough and a seat in the passage for a one-way valve which acts against downward fluid flow, a sealing surface on the body below said seat to engage a mating sealing surface on a well production string, said body also having port means therein extending as a bypass around said seat and from the outside of the body above its sealing surface and into said passage below said seat, a balanccd valve having upwardly facing and downwardly facing areas and normally closing said bypass and having a limited range of upward travel relative to said body from by-pass closed position to by-pass opened position, the upwardly facing and downwardly facing areas of said balanced valve being substantially equal for a balance of fluid pressure thereon, stop means on the body engageable by said balanced valve to establish its limit of 'up- Ward travel, said balanced valve having a coupling connector for pickup engagement by a pulling tool and trans mission of upward pull to effect upward travel of the balanced valve to bypass open position and thereafter to lift the balanced valve and the body as a unit.

2. A retrievable standing valve for wells, including a tubular body whose lower end is for sealed anchorage with a part of a well string and has an internal passage therethrough and whose upper end includes an upwardly facing valve seat and a valve cage above said seat and terminates in a headed pin having reduced neck and being for detachable suspension with a landing tool, a downwardly seating one-way valve contained within the cage, said body in the region between said valve seat and said pin having an opening therethrough for fluid flow from the cage and said body in the region below said valve seat having a valve by-pass port extending from said passage to the outer periphery of the body for fluid flow through said passage, a pulling tool engageable member having an upper portion slidably sleeved on said neck portion of the pin within upper and lower limits defined by the length of the neck portion and having a lower portion slidably sleeved on the body in by-pass port overlapping and closing relation at the lower limit and movable upwardly to uncover said by-pass port and also having a connecting portion joining said upper and lower sleeved portions and being formed with a flow opening for co-operation with the aforementioned flow opening in the body and a releasable connection between the body and said member retaining them against relative slide movement from by-pass closing relation and with said flow openings in alignment with one another until.

such time as a irelease force is exerted through pulling tool engagement with the upper sleeve portion.

3. In a standing valve unit for wells, an inner member to have sealed seating engagement with a well string and terminating upwardly in a landing tool engaging pin, said inner member having a main flow passage controlled by a one-way valve for retention of a standing fluid column thereabove and a secondary passage in valve by-pass relation, an outer sleeve member slidable upwardly on said inner member from a lowered position closing said secondary passage to a raised position uncovering said secondary passage and terminated upwardly in a pulling tool engageable head sleeved on said pin and a shearable pin connection joining the outer member to said inner member in said lowered passage closing position.

4. In combination with a well production string landing nipple having an upwardly facing landing seat, a standing valve assembly adapted for connection with a wire line for lowering and raising the standing valve assembly to and from seated position in the landing nipple, said standing valve assembly including a hollow valve body having a valve cage and a central pin projecting upwardly from the valve cage and terminating in a headed formation for releasable connection with a wire line lowering tool, a downwardly seated check valve contained within the cage, said cage having a flow opening through the wall thereof above said check valve, a downwardly facing landing shoulder formed externally on the valve body below said cage for co-operative engagement with said upwardly facing nipple landing seat, said valve body below said cage and above said landing shoulder having a port through the wall thereof, a raising tool engageable tubular part sleeved on the upwardly projected central pin and slidable on the pin between upper and lower limits, a shear pin connection between said pin and said tubular part holding the latter at its lower limit until the shear pin is sheared in response to raising tool force applied to the tubular part, a sleeve slidably fitted to the valve body and fixed to said tubular part by an inwardly extending wall overlying the wall of said cage and having a flow opening positioned by reason of said shear pin connection in alignment with the flow opening through the cage wall, said sleeve in response to raising tool force being slidable upwardly on the valve body away from a position in which the sleeve overlaps and closes the aforementioned port in the shear pin held position of said tubular part and to a port opening position, and said sleeve, together with said inwardly extending wall, and the tubular part in fixed relation to the sleeve having opposed surfaces in balanced relation to fluid pressure applied thereto.

5. A wire line retrievable standing valve comprising slidably interfitted inner and outer members, the inner of which is a hollow body to be received at its lower end in a retaining nipple of a well production string and having a domed valve cage at its upper end and a central pin projecting upwardly from the domed cage to a wire line lowering tool connector formation and the outer of which members is a tubular sleeve having a cap portion overlying said domed cage, a large diameter lower sleeve portion slidable on said body and a small diameter upper sleeve portion slidable on said pin between upper and lower limits and provided with a wire line pulling tool connector formation, a downwardly seated check valve contained within the cage to close said hollow body, said cage and said cap portion having aligned fluid flow openings therethrough above the seated check valve and said hollow body below the check valve having a lateral port through the wall thereof positioned to be closed by said large diameter sleeve portion at the sleeve lower limit and to be uncovered for by-passing fluid around said check valve at the sleeve upper limit.

6. The standing valve of claim 5, together with a shear pin connection joining the inner and outer members at the lower sleeve limit and which shears in response to Wire line pulling tool force transmitted to said pulling tool connector.

7. The valve of claim 5 wherein the outer member presents upwardly and downwardly facing surfaces for exposure to fluid pressure in substantially balanced relation to one another.

8. In a wire line retrievable standing valve, a hollow body having a lower landing portion and an upper re duced diameter central pin projected upwardly and terminated in a lowering tool connector head, a downwardly seating check valve contained within the hollow body to close the same against fluid downflow, the wall of said body between its landing portion and said check valve having an opening therethrough for by-passing fluid downflow around said standing valve, means normally closing the by-pass opening including a tubular portion slidably sleeved on said reduced diameter pin between upper and lower limits and provided with a dependent sleeve slidably fitted to the hollow body in overlapping relation to said by-pass opening at the lower slide limit of said tubular portion, said tubular portion having a pulling tool connector head for response to upward pull of a wire line pulling head connected thereto to first raise the sleeve for uncovering said by-pass opening and later raise the hollow body therewith by abutment of the tubular portion with the pin terminal head defining the upper slide limit of said tubular portion.

9. In a standing valve to be retrievably mounted in a well production tubing, a valve body having a passage therethrough and a port extending from the passage to the outside of the body, sealing means on the outside of the body below said port for sealing engagement with a production tubing in the mounted position of the standing valve, a sleeve overlapping said port to close the same and being slidable upwardly on the body to uncover said port, a coupling member on the body above said sleeve for member attachment directly to a lowering tool and without tool connection with the port overlapping sleeve, a check valve closing said passage above said port against fluid downflow, a coupling member on the sleeve for member attachment to a pulling tool and through which said sleeve is lifted relative to the body on a first increment of upward travel of said attached pulling tool and abutment stops on the body and the sleeve arranged in spaced apart relation when the sleeve is in overlapping relation with said port and engageable with one another upon occurrence of said first increment of pulling tool travel to thereby carry the body upwardly with the sleeve upon further upward travel of the pulling tool.

10. In a standing valve as defined in claim 9 wherein said body and said sleeve have aligned openings therethrough for communicating the passage above the check valve with the outside of the sleeve and a breakable connection immobilizing the sleeve on the body to maintain said openings in alignment in the absence of a sleeve sliding upward pull exerted on the sleeve coupling member.

References Cited in the file of this patent UNITED STATES PATENTS 1,644,998 Gunn et al. Oct. 11, 1927 1,956,112 Willoughby Apr. 24, 1934 2,131,299 Reagin Sept. 27, 1938 2,752,861 Hill July 3, 1956

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