US2345865A - Differential stage lift flow device - Google Patents

Description

April 4, 1944. A. BOYNTON DIFFERENTIAL STAGE LIFT FL OW DEVICE Filed Dec. 8, 1939, 2 Sheets-Sheet l N 0 T N V 0 5 n E D N X t L A Fig 5.

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April 4, 1944.

A. BOYNTON DIFFERENTIAL STAGE LIFT FLOW DEVI CE Filed Dec. 8, 1939 2 Sheets-Sheet 2 ATTORNEYS.

Patented Apr. 4, 1944 UNITED STATES PATENT FFICE 2,345,865 7 DIFFERENTIAL STAGE LIFT FLOW DEVICE- Alexander Boynton, San Antonio, Tex. Application December 8, 1939, Serial No. 308,317

g 8 Claims. (01.137-153) My invention relates to stage lift flowing devices for expelling liquids from wells, especially oil wells.

The principal objects are to provide: (1) a valve that will meter the pressure fluid to the well liquid in proportion to the volume of such liquid being lifted; (2) means for holding the valve closed against momentary fluctuations in the differential; (3) means for admitting pressure fluid into the device in such manner as will not cut nor abrade the valve mechanism; (4) construction which permits adjustments and replacements to be easily and quickly made; and (5) a device for such purposes which will be durable in operation and inexpensive to manufacture.

For these purposes, I employ a differentially operated combination sleeve and poppet valve having a shank extending through a metering chamber. I also employ a latch and/0r piston and check valve operable by an extension of the valve member.

The above and other objects are attained by mechanism described in this specification and illustrated by the accompanying drawings, in which Fig. 1 is a longitudinalsection through the preferred embodiment.

Fig. 2 is a cross section on the line 22, Fig. 1.

Fig. 3 is a cross section on the line 33, Fig. 4.

Fig. 4 is a partial longitudinal section through a-slightly modified form of pressure fluid intake and metering chamber showing the pressure fluid valve closed and the latch engaged.

Fig. 5 is a cross section on the line 5-5, Fig. 1. i

Fig. 6 is a cross section on the line 6-6, Fig. 1.

Fig; 7 is a cross section on the line 1-7, Fig. 1.

Fig. 8 is a cross section on the line 8-8, Fig, 1.

Fig. 9 is a cross section on the line 9-9, Fig. 1.

Fig. 10 is a cross section on the line |0|0 Fig. 1.

Fig. 11 is partially a longitudinal section and partially an outside view of a further modification of the invention.

Fig. 12 is a cross section on the line l2-I2, Fig. 11.

Fig. 13 is a cross section on the line l3-l3, Fig. 11.

Fig. 1g is a cross section on the line |4-I4, Fig. 11.

Similar characters of reference are employed to designate similar parts throughout the several views. 1

In Fig. 1 the nipple l is adapted to .be'threadedly joined into the' wel1 tubing string. Over this nipple the upper sleeve 2, having the projection 2a, is secured by the welds 2b. The lower sleeve 3, having the projection 3ais secured over the nipple l by the welds 3d and 3e.

The valve seat member 5 has threaded connection within the projection 3a and with the? lower end of the shell 4. The cover cap l4, ha,vinga rod-like upper extension I4d threadedly' connected into the projection 2a-of-the-member 2, has its lower expanded shell engaged over the bushing l3, which bushing is threadedly engaged within the shell 4. v

In assembling, the member 14' is screwed upward within the-projection 2w far enoughto allow the. connected members 4- and 5 to be screwed into the projection 3a. 'Then the member I 4 is screwed downward until its lower shell firmly engages over the upperend of the bushing l3. In this manner theshell 4 is secured in alignment with the nipple 1.; g r i i The head lb of the valve-rod 10 is yieldably positioned within the upper end of the metering chamber 4a by the engagement of the upper tubular extension lie of the piston I upon the nether side of the fins [3a ofthe bushing I 3-. This engagement is caused bythe coiled spring 9 preferably installed under some compression andhaving its upper extremity engaged under the piston II and its lower extremity engaged upon the ball roof 1. V a

The ball floor 6 maybe pressed into the shell 4 and landed uponthe slight internal annular shoulder 4c. The latch balls 8 are urged against the valve rod ID by the inner inclined surfaces of the members 6 and- Timparting the force of the spring 9. These balls are adapted to engage upon the latching surface of the restricted die ameter lflc of the rod [0 when .the valve lila is engaged upon-its seat 5c of the member 5. I

The untapered portion 521 of the latter member and hefl similar portionAb of.the member '4 preferablyv should be of the same length as the enlarged, straight portion Illb of the rod iii. The confronting metering chambers 4a and 5a preferably are flared as shown for the purpose of admitting a governed volume of pressure fluid into the eduction tube, the larger -volume preferably being admitted at approximately one half of the difierential force required to seat-the valvelfla. i

The piston ll, closely slidable within the. shell 4, may have a leak-proof engagement within this shell by means of the ring I2 which may be of leather or may be a series of metallic rings. The central opening Ho and the cross bores II I) admit pressure fluid to expand the ring I2 against the shell 4.

It will be observed that the pressure fluid actuates the piston I I by entering the upper end of the shell 4 via the openings Mo and I4!) and the chamber Ma.

The pathof the pressure fluid into the tubing is out of the annular space between the well casing and the tubing via the openings 4d, the chamber lie, the metering chambers 4a, 5a, the opening 5d, the chamber 30, and the aligned openings 3b and I a.

Falling slugs of well liquid frequently produce areas of false low differentials "within the eduction tube. These disturbances are temporary, but frequent, and their efiect is to cause ungoverned differentially operated valves to fly open and admit excessive volumes of pressure fluid during the flowing operation.

The latch balls 8 engaging upon the latching surface like prevent the valve 1 a from responding to such sudden disturbances in the differential. Preferably the latch should be adjusted to hold one fourth toone half of the unseating force exerted by the spring 9-. The latch may be adjusted by means of the nut lid. The threads shown in the upper end of the opening I Ia of the plunger extension II'c are for connecting a testing tool employed in "adjusting the latch.

A dashpot timing means within the chamber 14a of the member I4 is also provided to delay the opening of the valve Illa. The spring support bushing l5; threadedly engaged within the cover cap M, forces the sensitive spring IE to engage lightly under the wings Ila of the valve IT-. This valve has slight clearance, such as one or two thousandths of an inch, with the opening Mb; the fins IIa extending upward to provide such clearance. Whenthevalve a is traveling toward its seat 50, pressure fluid is drawn into the chamber I M and into the chamber 4f above the piston (see Fig. 4-), through the cross, bores I40 and the opening I ib; but when the valve Illa recedes from its seat, the pressure fluid entrapped between the piston II and the check valve I1 will escape very slowly through the slight clearance between the valve I I and the seat from which it is held slightly removed bythe wings Ila, as stated. The clearance between the valve I1 and its proximate seat may be varied'to provide the proper time element in thev opening of the valve I 0a, such as will prevent that valve from being actuated by falsedifierentials,

The openings 417., being much smaller than the metering-chambers and the openings 5d, 3b, and la, it is apparent that the pressure under the piston I I will be less thanthe pressure above it. This lesser pressure is communicated from the chamber 46 through the slight clearance between the rod I0 and the members 6 and I.

The pressure fluid intake openings, 4d are inclined toward the wall of the chamber 4e in order to prevent abrasive substances frequently present in pressure fluidfrom abrading the valve rod' It (see Fig. 5). I

Fig. 4, illustrating a slightly .modified form from Fig. i, has the nipple I8 threadedly joined to the members 3a and I9, and has formed within it the metering chamber I8a. The intake nipple I9 has the intake ports I9a confronted by the annular extension I81) of the member I8.

This extension operates as a baffle to shield the rod In from the abrasive action of the pressure fluid. When the valve Illa is seated, the latch balls 8 are engaged upon the latching surface Mic.

The space M in Fig. 4 will be filled with pressure fluid entrapped between the check valve ll (see Fig. 1) and the piston II where it will act to retard the opening of the valve IIJa, as was explained in connection with Fig. 1.

The parts bearing the same reference characters in Figs. 1 and 4 will be understood to be the same in purpose.

In Fig. 11, illustrating a further modification, the shell 20 is threadedly connected into the projection 3d and has its upper end threadedly engaged with the cap having a countersink in its upper end into which the stud 21 is engaged in order to secure the shell 20 aligned with the tubing nipple I.

The plunger 2.2 ha threaded connection with the rod 28 which rod is similarly engaged with the piston 24, having a close sliding fit within the shell 29. The locking screw 25 secures the rod 28 in pro-per position within the piston for the latch balls 8 to engage within the latching surface 28a when the valve 220 of the plunger 22 is engaged upon the seat 2342 of the member .23.

The spring 9, installed under som compression, is engaged between the ball roof I and the piston '26 and normally urges this piston to engage upon the lower end of the cap 26.

The packing I2 is urged against the shell '20 by pressure fluid contacting its inner surface via the recess 2% and the openings 24b. The valve seat member 23 may be pressed into the shell 20 and landed upon the internal annular shoulder 23c. The member 21 and the ball floor 6 may be fitted closely within this shell but the ball roof I and the shell should have some clearance between them in order that the latch action will be free.

The tubular extension 2Ic of the member 2I supports the ball floor 6 and has the openings 2Ib out of alignment with the intake openings Zila in order to provide a bafile to protect the metering pin 2211 from being abraded by foreign substances in the pressure fluid.

The metering pins 22a and 22b of the plunger 22 are convexly tapered in opposite directions, as appears in Fig. 11. The lower metering pin 22!) has diminishing clearance within the central opening 231) as the valve 220 approaches the seat 23a, while at the same time the upper metering pin has increasing clearance within the metering sleeve Zia in order that the greatest volume of pressure fluid will be admitted into the tubing when the valve 22c is approximately half way of its travel toward the seat 23a. Manifestly, the taper of these metering pins may be varied and the clearance which they respectively have within the central openings through the sleeve 2Ia and the member 23 also may be varied to correspondingly increase or decrease the flow of pressure fluid at any given diiierential.

, When the valve 220 and the seat 230. are engaged, a considerable volume of pressure fluid will be trapped between the piston 24 and the check valve II, aswas'explained in connection with Fig. 1. This entrapped pressure fluid will be discharged slowly past the valve I! and delay the opening of the valve 22c after the latch springs. The section Z2', Fig. 11, is the same as the section 22, Fig. l; likewise the section 'I'--'I', Fig. 11, is the same as the section 'i--I, Fig. l; but the members out are not identical; hence both of these sections are indicated as prime in Fig. 11 in order to avoid any possible confusion as to parts. 7

As the piston 24 travels downward, pressure fluid enters the chamber Ma and follows the piston via the openings I42: and I40.

In Figs. 1 and 11, the latch consisting of the members 6, 1 and 8 and the dashpot timing means consisting of the members l5, l6 and H, are similar in construction and identical in purpose.

The path of the pressure fluid through the device is out of the annular space between the tubing and the casing and into the tubing via the openings 20a and 2| 1), the clearance between the metering pin 22a and the sleeve 2 la, the chamber Zld, the opening 232), the chambers 20b and 3c, and the aligned openings 32) and la.

It will be understood that compressed air or gas, herein referred to as pressure fluid, will be employed as a power means for accomplishing flow of the well liquid through the eduction tube.

The pressure fluid force is constant at any given value thereof. The spring force is also constant while the force exerted by the upstanding column is variable, depending upon the level where exerted.

The liquid column caused to upstand in the tubing responsive to pressure fluid force in the annular space between the tubing and the casing, will be referred to as the upstanding column; and the lower liquid level in the annular space between the tubing and the casing will be referred to as the depressed liquid level.

It will be understood further that a portion of the upstanding column may be expelled from the well as a slug by admitting pressure fluid into it near its base or that expulsion of the well liquid will result from aeration, due to admitting pressure fluid at one or more places in the upstanding column which will be stretched or elongated by expansion of pressure fluid globules until flow is accomplished thereby.

The difference in pressures obtaining at the same level in the tubing and in the annular space between the tubing and the casing will be referred to as the difierential, that being the force which actuates the valves in all forms of this invention.

The devices are connected into the tubing string at intervals which may vary, 200 to 300 feet being i the usual spacing. This spacing, ordinarily, should be determined by the diiferential force required to seat the pressure fluid valves.

Preferably, the per square inch diiferential force required to seat the valves should be equal to. or somewhat greater than, the per square inch weight of well liquid between any two devices. Such adjustment will always cause a lower valve to be uncovered by the receding well liquid before the valve next above it will be closed.

The diameter of the piston being many times greater than the diameter of the valve that it controls, as shown, it is evident that the valve will be actuated in its movements and seated by a much greater force than can be employed to actuate and seat the usual valve which has the same seating areas as that employed to contact the seating force.

The value of the pressure fluid should be at least two or three times the diilferential force required to seat the valves, and may be much greater.

In Fig. 16, illustrating the installation plan in a well, the casing 29 has the tubing 30 suspended centrally within it. The casing head 32 accomplishes a hermetic seal between the tubing and the casing proximately above the ground surface 35.

The flow devices 3| are spaced at intervals which ordinarily may vary between 200 and 300 feet, as stated. The anchor string 38 may extend to the bottom of the well 36 to support part of the weight of the tubing. The intake nippl 3! may be joined between the tubing and the anchor string.

The formation 40 discharges its production into the well casing 29 via the gun perforations 39.

One side of the casing head is shown closed by the bull plug 34. Pressure fluid may be supplied into the annular space 44 from the pipe line 33 which may be connected with a compressor plant or a gas line. Manifestly, if the well produces enough gas to flow it, the opening in the casing head shown occupied by the pipe line 33 may be closed by a plug. The tubing 30 may extend to a flow tank or separator. T

The normal liquid level in both the tubing and the casing is assumed to be standing at 4!.

Now, to initiate flow, turn pressure fluid from the pipe line 33 into the annular space 44, the line 30 being open. The valve in each device will quickly close, due to increasing pressure in the annular space 44. The well liquid exterior of the tubing will soon be depressed to 42 and will upstand in the tubing to a level indicated at 43. The flow device nearest to the base oi the upstanding liquid column then will be intaking pressure fluid. The device next above will be closed or closing, depending upon the distance and weight of the well liquid between it and the base of the upstanding column.

Each device uncovered by the receding liquid level 42 will be open and intaking pressure fluid. while the one next above will be closing. This operation continues as the well liquid is expelled by stages in a manner well known to the art.

It is apparent that the device described as the preferred embodiment of the invention may be inverted from the position shown and operate equally well by virtue of inherent operating characteristics of the device.

The invention as herein illustrated and described is manifestly subject to many changes in construction and arrangement of parts which will remain within the scope and purpose of the stated objects and appended claims.

The invention claimed is:

1.. A well flowing device comprising a valve body having a passage'waywith spaced inlet and outlet openings and a valve seat proximate the one end thereof and leading from the exterior to the interior of the body, a metering chamber in the passageway intermediate said openings, a valve assembly movable in and adjacent to the passageway. said assembly including a valve member in the passageway, a piston in an opening adjacent the passageway, there being a pas sage to the side of the piston opposite said openings to admit fluid to the piston, a piston rod connecting the valve member and piston, a peripheral groove in said piston rod, a latch assembly surrounding the piston rod and including a plurality of latch balls adapted to releasably engage the piston rod when the valve member moves to a predetermined position, and a spring in the passageway engaging the piston and latch assembly to normally urge the valve assembly away from said seat and to urge' the latch balls to latching position within said groove.

2. A well flowing device comprising a body, a passageway for pressure fluid through a portion of said body, inlet and discharge openings in said passageway, said inlet openings communicating between said passageway and the exterior of said body, and said discharge opening communicating between said passageway and the interior of an other member of said body, a metering chamber within said passageway intermediate said intake and discharge openings, a valve seat proximate one end of said metering chamber, a valve normally positioned within said passageway and proximate the opposite end of said. metering chamber relative to said valve seat, a rod connected to said valve, a piston connected to said rod, said piston being slidable in a member of said body and having a peripheral groove containing packing and also having an extension with an axial opening communicating with cross bores leading to the inner surface of said packing, a check valvein said body, said valve having its surface cut by a slot, openings communicating between said check valve and the exterior of said body, a spring in said body resiliently urging said check valve upon its seat, another spring in said body, said spring being adapted to urge the piston and valve away from said seat. 1

3. A well flowing device comprising a body, a passageway for pressure fluid through a portion of said body, inlet and discharge openings in said passageway, said inlet openings communicating between said passageway and the exterior of said body and said discharge opening communicating between said passageway and the interior of.an

other portion of said body, a metering chamber within said passageway intermediate said intake and discharge openings, a valve seat proximate one end of said metering chamber, a valve normally positioned within said passageway and proximate the opposite end of said metering chamber relative to said valve seat, a rod connected to said valve and having an annular recess adapted to be engaged by a latch, a piston connected to said rod, said piston being slidable in a member of said body and having a peripheral groove containing packing and also having an extension with an axial opening communicating with cross bores leading to the inner surface of said packing, a latch in said body, said latch being adapted to engage balls within said annular recess of said rod, a spring in said body, said spring being adapted to urge the latch to close upon said rod, and to urge the piston and 7 valve away from said seat.

4. A nipple adapted to be joined into the tubing of a well, a tubular shell assembly adapted to be joined laterally with and parallel to said nipple, means for securing such joinder, a passageway for pressure fluid through a portion of said shell assembly, inlet and discharge open ings in said passageway, said inlet openings communicating between said passageway and the exterior of said shell assembly and said discharge opening communicating between said passageway and the interior of said nipple, an annular bafile member opposite said inlet openings, a metering chamber within said passageway intermediate said intake and discharge openings, an annular valve seat proximate one end of said metering chamber, a valve normally positioned within said passageway and proximate the opposite end of said metering chamber relative to said valve seat. a rod connected to said valve and having an annular recess adapted to be engaged by a latch, a piston connected to said rod, said piston being slidable in said shell assembly and having a peripheral groove containing packing and also having an extension with an axial opening communicating with cross bores leading to the inner surface of said packing, a bushing in said shell assembly, said bushing having wings adapted to be engaged by said extension of the piston, a check valve in said shell assembly, said valve having its surface cut by a slot, openings communicating between said check valve and the exterior of said'shell assembly, a spring in said shell assembly resiliently urging said check valve upon its seat, a latch in said shell assembly, said latch being adapted to engage balls within said annular recess. of said rod, a spring in said shell assembly, said spring being adapted to urge the latch to close upon said rod and the piston ,to engage said bushing,

5. A well flowing device comprising a valve body having a through passageway, a shell attached to said valve body and having a metering chamber with spaced inlet and outlet openings communicating with the exterior and interior of the valve body, a piston chamber in the shell communicating with said metering chamber, a valve and piston assembly within said chambers. said assembly including a piston in said piston chamber and a valve in said metering chamber intermidate the inlet and outlet openings, con necting means between said valve and piston, there being an opening in the piston chamber beyond the piston relative to said valve, a valve seat facing the valve in the metering chamber, and resilient means normally holding the valve and piston assembly in a position with the valve member in spaced relation to the valve seat. 1

6. A well flowing device comprising a valve body, a shell attached thereto and having a passageway with spaced inlet and outlet open ings proximate one end thereof, said body having a through bore and said openings and passageway constituting a passage between the exterior and interior of the body, a piston chamber having communication with said passageway, a metering chamber in the passageway intermediate said openings, a valve movable within said metering chamber to control th passage of pressure fluid from the exterior to the interior of the valve body, a valve seat confronting said valve member in said metering chamber a piston in said piston chamber, means for connecting said valve member and piston, a spring within said piston chamber normally urging the piston and valve so that the valve is spaced from said valve seat, and means for admitting pressure fluid to the side of said piston opposite said spring, said last mentioned means including a leaky check valve whereby the movement of the piston and valve away from said seat is retarded.

'7. A well flowing device comprising a valve body having a through passageway, a shell having a chamber with spaced inlet and outlet openings proximate one end thereof, said openings communicating respectively with the exterior and interior of the valve body, saidchamber comprising oppositely flared walls having an annular valve seat about the outlet opening, a valve member movable within said chamber to control the passage of fluid therethrough and to move into engagement with said seat to close the passage, and means resiliently holding the valve in spaced relation with its seat and operable by the differential pressure between said chamber and the exterior of the valve body to control the flow of pressure fluid to the interior.

'Of the valve body.

8. A well flowing device comprising a valve body having a through passageway, a shell having a chamber with spaced inlet and outlet openings proximate one end thereof, said openings communicating respectively with the exterior and interior of the valve body, said chamber comprising oppositely flared walls having an annular valve seat about the outlet opening, a valve member movable within said chamber to control the passage of fluid therethrough and to 10 move into engagement with said seat to close the passage, means resiliently holding the valve in spaced relation with its seat and operable by the differential pressure between said chamber and the exterior of the valve body to control the flow of pressure fluid to the interior of the valve body, and means for releasably latching the valve in engagement with said seat.

ALEXANDER BOYNTON.

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