US3105509A

US3105509A - Well chamber valve

Info

Publication number: US3105509A
Authority: US
Inventors: Jr Howard H Moore
Original assignee: Camco Inc
Current assignee: Camco Inc
Priority date: 1960-11-14
Filing date: 1960-11-14
Publication date: 1963-10-01
Anticipated expiration: 1980-10-01

Description

Get. 1, 1963 H. H. MOORE, JR 3,105,509

WELL CHAMBER VALVE Filed Nov. 14. 1960 2 Sheets-Sheet l H H. Moore,

INVENTOR.

BY QC 1M ATTO/P/VfK Oct. 1, 1963 H. H. MOORE, JR 3,105,509

WELL CHAMBER VALVE.

Filed Nov. 14. 1960 2 Sheets-Sheet 2 f/TZA H H Moo/ 6, z/r. 7 INVENTOR.

BY 9Q IMZQ ATTORNEY United States Patent 3,105,509 WELL CHAD BER VALVE Howard H. Moore, .l'r., Houston, Tern, assiguor to Qarneo Incorporated, Houston, Tex, a corporation of Texas Filed Nov. 14, 196%, Ser. No. 68,944 4 Claims. (Cl. 137-1ll2) This invention has to do with the production of well fluids through the use of a gas lift system incorporating a downhole liquid accumulation chamber, and more particularly to an improved valve assembly operating in response to controlled pressures of lift gas supply for alternately venting the chamber to promote liquid inflow and pressuring the chamber for pneumatic ejection of accumulated liquid from the bottom of the well to the well head.

Conventional chamber installations usually involve an enclosed storage cylinder within the well hole to receive well fluid from an adjacent packed ofi producing stratum and a production tube extends to the bottom of the chamber in annular clearance relation thereto and as an outlet from the chamber with a small pressure equalizing bleed port communicating the chamber at an upper level into the eduction tube. Well casing containing lift gas whose supply and pressure are varied at the surface, is periodically valved into the top or" the chamber to evacuate liquid accumulated during a previous noninjection phase of the cycle. To effect such evacuation without substantial pressure loss through a constantly open bleed port or ports, the size of the ports needs to be relatively small and the smallest of a constantly open vent presents design limitations, with clogging problems and the need for frequent maintenance attention.

An object of the present invention is to eliminate small metering vents and their attendant objections and to provide a retrievable valve unit whose maintenance can be easily attended to by valve removal without the need for tubing removal.

A further object of the invention is to provide an improved chamber valving arrangement of simplified design for reasonable initial installation cost and for materially reducing servicing expense whereby to encourage more widespread adoption of chamber installations and the continued operation of low production wells which otherwise might be closed down as unprofitable.

Another object is to provide an automatic valve unit which acts to control both a large open vent from and a pressure lift gas inlet to the upper end of an accumulation chamber and provides for efiective chamber venting into the eduction tube alternately with lift gas pressurization of the chamber without loss and diversion of lift pressure through an open Vent, which is to say that the chamber vent and pressure gas inlet are opened and closed in out of phase relationship.

Still another object of the invention is to provide an improved assembly containing a piston operated valve which moves from a chamber venting position at one point in the piston stroke at which the vent is open and the pressure lift gas inlet is closed and to a gas injection position at another place in the range of piston stroke at which the pressure gas inlet is opened and the vent is sealed and diverts all pressure gas to the performance of usetul work in the storage chamber and which valve responds to pneumatic pressure thereon from lift gas supplied during an injection phase of the cycle.

A further object of the invention is to provide a lift gas actuated master valve to deliver pressure gas to the cylinder of a slave valve actuating piston with a cylinder contained check valve which, during a chamber venting phase, closes the master valve gas deli-very passage into the piston cylinder and elirrinates influence on the master ice valve of pressure variation within the accumulation chamber.

A still further object of the invention is to provide a tretrievable type chamber control valve unit which can be quickly and easily dropped into and removed from operating position by use of conventional wire line equipment and without disturbing tubing string installation and other components of a well system.

Other objects and advantages will be evident from the following description and the accompanying drawings wherein FIG. 1 is a transverse section showing a bottom hole installation in accordance with the invention; FIGS.

2A and 2B are elevations partly in section of the improved valve in its detail arrangement illustrating the parts in position to vent the chamber and seal oi the flow of pressure gas; FIG. 3 is an elevation partly in section showing the valve elements in the position in which the vent is sealed at the time the lift gas valve is open and FIG. 4 is a fragmentary sectional view of modified type of master valve head having balanced opposing faces to exclude tubing pressure efiect thereon.

Referring to the drawings, the fragment of a well bore as seen in FIG. 1 is lined by a casing 1 which intersects and is perforated into a well producing formation 2. Just above the formation 2, an annular packer 3 surrounds a bot-torn portion 4 of an eduction tube 5 and seals the annulus space 6 above the packer from the production formation 2. At its lower end the tube 4 contains an inwardly opening standing valve '7 for the inflow of formation fluid when its pressure exceeds that within the tubing string and the valve 7 closes against backfiow when tubing pressure exceeds formation pressure. Above the packer 3, the eduction tubing *5 has a laterally enlarged section and a. partition which provides a side pocket 9 laterally oilset from the through passage 14 Within the passage in in the region of the partition wall 8 there is contained an annular packer ill from which depends an extension tube 12 whose open lower end is adjacent the bottom of the tube 4. Tim's extension tube 12 is of smaller diameter than the tube portion 4 and is impertorate throughout its length, whereby the intervening annular space 13 provides the chamber for liquid accumulation.

At its upper end the accumulator chamber 13 is blanked oil from the eduction passageway 10 by means of the packer '11 but it opens into the bottom of the side pocket 9 whose upper end is open to the passage 10. In normal use of the system, free communication between the upper and lower ends of the pocket 9 is blanked oil by a retrievable valve unit 14 in accordance with the present invention and this valve unit can be deposited in and removed from the side pocket 9 by conventional wire line equipment. 'For detachable co-operation with wire line equipment, the upper end of the unit 14 is provided with the usual fishing head and preferably also has latch mechanism for relasably holding the tool in position in its receiving pocket 9. A pair of spaced apart packing rings 15- 15 are peripherally carried by the body of the valve unit 114 for a sealing fit with the interior of the pocket 9 and the space between the upper and lower packings 15 communicates by way of a lateral port .16 in the pocket wall with the casing annulus space 6. The valve unit 14 is so constructed that during an operating cycle and when gas pressure within the annulus 6 is below a given degree, communication from the entry port 16 to the top of the chamber 13 is closed and the top of the chamber communicates through the valve unit with the eduction passage 10 above 'thepacking ll. Internal pressures the chamber 13 are thus equalized with the eduction tube pressure throughout its length. On the other hand, when casing annulus pressure rises and exceeds a given point, a

pressure responsive valve action occurs to close oil com- Patented 0st. 1, i963 pletely the vent path from the top of the chamber 13 and liquid being blown upwardly from the bottom and through the extension tube 12 and on upwardly in the eduction tube '5 to the surface. Pressure gas supplied to the annulus can be controlled by a timer actuated valve adjusted to suit production capabilities of the particular well, so that the delivery of pressure is interrupted for a sulficient time interval to assure accumulation of a desired amount of well fluid within the chamber and the production tube and is then supplied to build up pressure suficient to elevate the accumulated liquid to the well head.

in detail, the improved valve unit 14- is shown in the companion views 2A and 2B. For convenience of manufacture and assembly, the outer body or hollow housing enclosing the operating components is made up of an end to end succession of threaded together

tubular sections

14a, 14b, 14c, 14d, Me and def, with the previously referred to packing rings l5 indicated in each instance as being a succession of V-sectioned seals of which the upper group is clamped between co-operating shoulders of the

body elements

140 and 14d and the lower of which is clamped between the

body elements

14c and 14 The lowermost body section 14 is a downwardly tapered nose piece or cone having ports therethrough forming a part of a passageway extending longitudinally within the body. A replaceable annular valve seat 17 is clamped between adjoining end portions of the

body sections

14c and 14d and the wall side ports '13 aligned with a peripheral annular groove therein in a region between the upper and lower packings l5-15 for approximate alignment with the side port '16 in the wall of the eduction tube 5. This side port 18 provides an entry passage for the inflow of pressure gas to the inside of the valve body.

In upwardly spaced relation to the upper packing 15, the body section 14c has one or more lateral ports 19 in its wall, communicating outwardly with annular clearance space surrounding the valve body and within its receiving pocket 9 for venting into the eduction tube from the interior of the valve body. Formed separately from the body section 1140 and enclosed thereby in annular clearance relation is a piston cylinder 20 having peripherally thereof a series of circularly spaced apart and longitudinally extended ribs 21 in an intermediate portion of the length of the cylinder and of an outside diameter substantially corresponding with the inside diameter of the body section 14c. When, for example, there are four equally spaced apart vent ports 19 in the wall of the body section 14, then there also will be four of the circularly spaced apart ribs 21, each having a lateral port 22 aligned with a corresponding side port v19 as a continuation thereof. For properly locating the cylinder \20 with the ports .19 and 22 in alignment, the bottom edge. of each rib 21 is seated on an internal shoulder, as at 23, on the body section 14c and the parts may additionally be soldered or welded together. The annular space surrounding the outside of the cylinder 20 along with the longitudinal channels occurring between the circularly spaced apart ribs 21, provide a passageway around the outside of the piston cylinder for a purpose later to be referred to. V

The interior of the cylinder 20 in the region of the

vent ports

19 and 22 has two portions of stepped diameter for slidable reception of a stepped diameter skirt of a piston 24 and such stepped diameter relation provides an upwardly facing abutment shoulder 25 internally of the cylinder just below the side ports 22 and a co-operating downwardly facing abutment shoulder 25 on the piston just above one or more lateral ports'26 leading through 'the skirt of the hollow piston from the central internal passage contained in the piston. -In the illustration of FIG. 2A, the piston is at its upper limit of slide travel so that

theseveral side ports

26, 22 and 19 are in vent estaband rod being separately formed and joined together at their adjacent ends by screw threads. The hollow rod portion extends downwardly below the-valve element 27 and has one or more latenal openings 29 communicating the annular space below the valve seat 17 with the interior of the hollow rod whose lower end is open and communicates with the openings in the body nose piece 14]. Also, as seen in FIG. 2B, this lower portion of the rod is of reduced external diameter and is slidably guided Within the correspondingly reduced internal diameter of the lower portion of the body section 1 42 and against the upper shoulder of which is grounded the lower end of a compression coil spring 30 which bears upwardly on anex ternal rod shoulder for yieldingly biasing the piston rod upwardly to the limit established by the interengagement of the

valve seats

27 and 17. This relative position of the parts establishes the chamber vent position.

Above the head of the piston 24 at its uppermost limit is an upper cylinder space which slidably receives a shiftable wafer or disc 31, preferably of an elastic nonmetallic material, affording an upwardly acting check valve. In its uppermost position, as shown in FIG. 2A, the disc 31 bears against the bottom face of a centrally apertured valve seating ring 32 held within the upper end of and against an upwardly facing internal shoulder V in the piston cylinder 20, by a retainer such as a snap ring 33. Preferably, the valve disc 31 has a centrally disposed conical button on its upper face for a self centering and closure seating relation with the aperture through the annular seat 32. Small peripheral clearance around the disc 31 will aiford a pressure relief path toward the V vent port 22 and by way of either or both peripheral clearance at the head of the piston and a bleed port 34 through the piston head. i

The top of the ring 32 provides an aperture surrounding annular seat for co-operation with a tapered valve tip on the lower end of a stem' 35 projecting downwardly from a closure head 36 on the free or movable end of a tubular flexible Wall or corrugated metal bellows 37 enclosed within the tubular body section 14b and sealed at its upper end to a closed pressure gas confining chamber within the body section 14a. Pressure gas confining in the chamber provides elastic bias to depress the head 36 as accommodated by bellows expansion and seats the valve 35. The chamber space within the body section 14b and'surrounding the movable head 36 is open downwardly through annular space surrounding the cylinder 20 and leading through the exterior clearance about the piston rod 28 to the gas entry port 18. At all times during use the free end of the bellows is exposed to casing gas pressure. In operating cycle intervals between casing pressure build-up, the master valve 35 will be seated, as shown in FIG. 2A, by force of the bellows confined pressure gas. Throughout the noninjection phase, cylinder pressure above the piston 24 and by reason of the bleed port 34-, will equal tubing and chamber pressure, with the biasing coil spring 30 holding the slave valve 27 closed and the

vent ports

26, 22 and 19 in open aligned relation. Tubing pressure increase will tend to lift the valve disc 31 against the seat 32 and exclude action on the tip of the master valve 35 within the bleed port 34 and transmit the pressure to the piston 24 for moving it downwardly against the coil spring 3-1) to the position illustrated in FIG. 3, wherein the vent port 26 in the piston is out of alignment with and below the

vent ports

22 and 19. At the same time, the slave valve 27 is depressed from its annular seat 17 and casing pressure lift gas flows directly from the entry port 18 without vent port leakage and downwardly into the top of the accumulation chamber for full pressure utilization in clearing out accumulated liquid and raising the same to the surface. Upon completion of the ejection phase of the cycle, the drop in casing pressure allows restoration of the valve parts to the original chamber venting relation and a repetition of liquid accumulation above the standing valve 7.

As an alternative for the master valve tip 35 and for minimizing extremely close manufacturing tolerances and for use either with or without the check valve 31, there is illustrated in FIG. 4 a valve tip 135 comprising a guide stem and an enlarged head, both slidably fitted to a stepped diameter bore in a body section vll -tb and provided peripherally with annular O-rings to seal a chamber space within the body section and above the a shoulder 135a between the stem and head. A drilled passageway 135b in the valve communicates the sealed off chamber space with the port through the valve seating ring 132 and when the valve is seated with the vent open, pressure within the space above the shoulder 135a will be that of tubing pressure. Equal oppositely facing surface areas on the shoulder 135a and at the bottom of the valve head inside the annular seat 132 balance out tubing pressure eifect and pressure fluctuations on the master valve, wherefore its control is dependent solely on casing pressure on the bellows. The structure otherwise is as previously described.

The foregoing specific description relates to a preferred embodiment of the invention and it will be understood that such modifications can be made as come within the scope of the appended claims.

What is claimed is:

1. In a valve assembly for a well producing gas lift system, a housing having through the side wall thereof an upper vent port and a lower pressure gas entry port, a downwardly facing annular valve seat in the housing below said entry port, means in the housing below said valve seat for communicating the housing interior with a part of the system whose pressure is to be controlled, an elongated hollow rod reciprocably mounted in the housing in lapping relation to both ports and spaced laterally from the housing in the region thereof between the gas entry port and said valve seat as a flow passage therebetween, and annular valve seat carried by the rod for seat ing engagement with the housing valve seat at the upper limit of rod reciprocation and movable downwardly with the rod away from seating engagement, said hollow rod having its interior hollow space open into the housing below said valve seat and also having a side port positioned therein to be aligned with and to communicate the upper vent port with the hollow space of the rod at said upper limit of rod reciprocation and to be in port closing misalignment with the vent port at the lower limit of rod reciprocation, spring means interposed between the housing and said rod and active to bias the rod upwardly, an actuating piston at the upper end of the rod, a piston receiving cylinder in the housing, a pressure gas chamber contained within the housing in constant communication with said gas entry port and in valve controlled communication with the piston chamber, a normally closed master valve controlling communication to the piston cylinder from said chamber and a pressure responsive device enclosed by said pressure gas chamber and connected with the valve to open the same in response to a predetermined gas pressure within said chamber. 7

2. In a valve assembly as in claim 1, a transverse partition in the housing separating said cylinder and said 6 V a pressure gas chamber and having a communicating opening therethrough and over which the master valve seats downwardly, said piston having a bleed opening communicating the upper cylinder space with the interior of said hollow rod and a check valve member shiftably contained in the upper cylinder space and adapted alternately to seat upwardly against said partition to close its communica-ting opening and to seat downwardly on the piston.

3. In a valve assembly for a well producing gas lift system, a housing having a vent port and a :gas entry port spaced apart in the side wall thereof, a partition in the housing subdividing the same into a pressure gas chamber and a piston cylinder and having a chamber and cylinder communicating port through the partition, a gas pressure responsive valve in said chamber normally closing the partition port and movable to open the partition port at a given chamber pressure, a piston having a head and a dependent hollow skirted portion reciprocally con-- tained within the cylinder and movable from a top limit to a bottom limit under gas pressure passed through said partition port and against the piston head, an outlet below the gas entry port, seat means in said housing between the gas entry port and the outlet, said skirted portion cooperating with said seat means to prevent communication between the entry port and the outlet at the upper piston stroke and to open communication between the entry port and the outlet at the lower piston stroke, said skirted portion lalso comprising means to provide communication between the vent port and the interior of the hollow skirted portion at the upper piston stroke and to close the vent port at the lower piston stroke, said piston head having a bleed port therethrough, and a check valve shiftably mounted within the cylinder between the piston head and said partition and co-operating with said partition port and said bleed port to close one and open the other and vice versa.

4. In a valve assembly for a well producing gas lift system, a housing having spaced apart chambers one of which has a fluid fiow passage for connection with a system portion to be alternately vented and pressurized under control of the valve assembly, an apertured partition between said chambers, said one of e chambers having in the Wall thereof a pair of zones of different internal diameter and with the zone of smaller diameter adjacent and co-operating with said partition to afford a piston receiving cylinder, said housing having a pair of lateral ports, one extending through said wall at the smaller diameter zone as a vent and the other extending through said Wall in the larger diameter zone as a pressure gas entry port and said wall also having 'a longitudinal passage through the smaller diameter zone communicating the entry port with the other chamber, a pressure responsive valve in the last mentioned chamber normally closing the apertures of said par-tition and movable to open the aperture at a given pressure of gas applied thereto, an annular valve seat carried by the housing intermediate said pressure gm entry port and said fluid flow passage, an elongated hollow rod reciprocally mounted within said one of the chambers in annular spaced relation with the chamber wall in its larger diameter zone to afford a passage between the entry port and said valve seat and provided with a piston head portion closely slidably fitted to the chamber Wall in its smaller zone for receiving pressure gas delivered through the aperture into the cylinder to effect an outward stroke of the hollow rod, spring means mounted on the housing and bearing on the rod in opposition to the action thereon of pressure gas in said cylinder, a peripheral valve forma tion on the rod having closing engagement with said annular seat at the inward stroke limit of the hollow rod and said piston head portion having a lateral port aligned with the vent port at said inward stroke limit and movable with the piston head portion to an out of alignment and closing relation with said vent port.

(References on following page) References flied 1'11 the file of this patent UNITED STATES PATENTS Buerkle May 8,1906 White Mar. 3, 1931 5 Jennings Jan. 3, 1939 Stephens Jan. 3, 1939

Claims

1. IN A VALVE ASSEMBLY FOR A WELL PRODUCING GAS LIFT SYSTEM, A HOUSING HAVING THROUGH THE SIDE WALL THEREOF AN UPPER VENT PORT AND A LOWER PRESSURE GAS ENTRY PORT, A DOWNWARDLY FACING ANNULAR VALVE SEAT IN THE HOUSING BELOW SAID ENTRY PORT, MEANS IN THE HOUSING BELOW SAID VALVE SEAT FOR COMMUNICATING THE HOUSING INTERIOR WITH A PART OF THE SYSTEM WHOSE PRESSURE IS TO BE CONTROLLED, AN ELONGATED HOLLOW ROD RECIPROCABLY MOUNRED IN THE HOUSING IN LAPPING RELATION TO BOTH PORTS AND SPACED LATERALLY FROM THE HOUSING IN THE REGION THEREOF BETWEEN THE GAS ENTRY PORT AND SAID VALVE SEAT AS A FLOW PASSAGE THEREBETWEEN, AND ANNULAR VALVE SEAT CARRIED BY THE ROD FOR SEATING ENGAGEMENT WITH THE HOUSING VALVE SEAT AT THE UPPER LIMIT OF ROD RECIPROCATION AND MOVABLE DOWNWARDLY WITH THE ROD AWAY FROM SEATING ENGAGEMENT SAID HOLLOW ROD HAVING ITS INTERIOR HOLLOW SPACE OPEN INTO THE HOUSING BELOW SAID VALVE SEAT AND ALSO HAVING A SIDE PORT POSITIONED THEREIN TO TO BE ALIGNED WITH AND TO COMMUNICATE THE UPPER VENT PORT WITH THE HOLLOW SPACE OF THE ROD AT SAID UPPER LIMIT OF ROD RECIPROCATION AND TO BE IN PORT CLOSING MISALIGNMENT WITH THE VENT PORT AT THE LOWER LIMIT OF ROD RECIPROCATION, SPRING MEANS INTERPOSED BETWEEN THE HOUSING AND SAID ROD AND ACTIVE TO BIAS THE ROD UPWARDLY, AN ACTUATING PISTON AT THE UPPER END OF THE ROD, A PISTON RECEIVING CYLINDER IN THE HOUSING, A PRESSURE GAS CHAMBER CONTAINED WITHIN THE HOUSING IN CONSTANT COMMUNICATION WITH SAID GAS ENTRY PORT AND IN VALVE CONTROLLED COMMUNICATION WITH THE PISTON CHAMBER, A NORMALLY CLOSED MASTER VALVE CONTROLLING COMMUNICATION TO THE PISTON CYLINDER FROM SAID CHAMBER AND A PRESSURE RESPONSIVE DEVICE ENCLOSED BY SAID PRESSURE GAS CHAMBER AND CONNECTED WITH THE VALVE TO OPEN THE SAME IN RESPONSE TO A PREDETERMINED GAS PRESSURE WITHIN SAID CHAMBER.