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Publication numberUS1833778 A
Publication typeGrant
Publication dateNov 24, 1931
Filing dateNov 3, 1924
Priority dateNov 3, 1924
Publication numberUS 1833778 A, US 1833778A, US-A-1833778, US1833778 A, US1833778A
InventorsFletcher Harold W
Original AssigneeHughes Tool Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Pneumatic discharge swab
US 1833778 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

l Nov. 24, 1931. H. w. FLETCHER PNEUMATIC DISCHARGE swAB Filed Nov. 3, 1924 IMM EN @@w @Mo-m @Houma Patented Nov. 24, 1931 i errar cria mom) w. FLETCHER, or HoUs'roN, TEXAS, Assienon. :ro mismas Toor. contr,4

OF HOUSTON, TEXAS, A CORPORATION OF TEXAS IPNEUMATIQ DISCHARGE SWAIB Application led November 3, 1924. :Serial No. 747,631.

which comparatively large quantities of liquid may be draw-n from the well without the usual wear and clogging ofthe apparatus ldue to sand.

' ,Another object is to provide means forexpelling repeated charges of oil from an oil well bypneumatic pressure inl such manner that the sand and other impurities will be carried forcibly out with the charge of liq- A uid, thus allowing the oil to flow freely into the well hole from the producinglstratum.v

Another object is to provide mechanically controlled means for regulating the 4discharge of the swab and liquid from the well,

when the .proper pneumatic pressure is ob, tained. It'is desired thereby to raise the liq` uid'from the well with force, so that the sand and other impurities will be cleaned from thel I well by the operation ofthe device.

` y -Another object is to provide a swab plun g- -openjwhenthe plunger .is descending and erandV cooperating mechanism, .whereby the plunger valve may be automatically held .closed when said plunger is rising.

# j Referring t'oth drawings, herewith, Fig.

j. Other'objects and the means by which they arey accomplished willV be clear from the-more detailed description which followsz' i `1 is a central longitudinal section through a device embodying'my invention: Fig. 2 is a similar view showing the parts in diilerent position. Y Fig. 3 is a central longitudinal sec-V tion of the swab piston and its support. `Like 4 4numerals'of reference are employedto designate like parts in all the views. f

In carryingout my inventionI employ a v` casing 1 of ordinary construction within the wells, the joints of the casing being made up tightly so as to make .theI same fluid tight.y The upper end ofthe casing is threaded for. engagement with the casing head 2, having ay laterally branchedpipe thereon to allow the entrance'of air or gas on pressure.

The upper end of the casing head is provided with a stung box, including packing 4:, which is compressed thereon by al gland 5, which v is clamped in adjusted position bolts 6. l

The tube7 is fitted within the stuiii'ng box, thus provided, and projects downwardly into the well to the level desired. This tube may be of ordinary tubing or drive pipe, such as I contemplate employinga packer 130i any ordinary constructionL to close the space between the tube 7 and the casin at a point within thetubing, but will limit its upward movement within the chamber between the tubing and the casing. Spaced .above the packer is a coupling 12, connected Vwith the packer 13,' by the pipe 14. Its upper end is v threaded for connection with the tube 7, and said tubing is perforated at 17 immediately aboye the coupling. lSaid coupling 12 has an below the level of the-liquid wit in the well.' This-will allow the liquid to pass upwardyinner flange 15 forming va seat for the coiled spring 16, which serves as 'a' support for the l shoe 18, The spring surrounds the lower en'd of the said shoe and bears against a radial Harige 19 fitting loosely within the tubing.

-T e swab p iston20 is designedto normally rest upon the flange 19, and said piston is therefore. open at the lower end, and tele scopes over the upper end` of shoe 18 as shown in Fig. 3. The piston is cylindrical in shape having its upper end closed except for the downwardly beveled opening 21,.forming a seat for the valve head 22,'shape'd to lit there`` on. The said valve hasa downwardly ex- -tended .stem litted through a diametrical guide 25, and having the head 26 at its lower end. It is heldresiliently upwardly within its seat by means of a compression spring 24.

The upper end of the valve is provided with a pin 23, adapted to contact with the s top pm 11 of the tubing cap previously described.

The lower head 26 ofthe valve is provided with upper shoulders thereon to engage with latching dogs, a pair of which is shown 1n position below the guide 25v pivoted to arms 32, which extend downwardly from the guide. The upper ends of the dogs are extended iiiwardlv and have shoulders 28 thereon to engage above the head 26. The lower ends of the dogs are provided with beveled cam faces 29 which act to engage with the inclined surface 31 at the upper end of the shoe 18 and thus to be forced inwardly by the downward movement of the plunger. The spring 30 between the lower ends of the two dogs is under compression. and tends to force the lower ends of the dogs outwardly.

The openings 17 in the tubing are normally closed by means of a sleeve valve 33, tittlng closely around the tubing and of sufficient length to close all of the openings in the tubing. This sleeve is secured at its upperend to a cable or wire 34, which is carried upwardly to the surface and passes outwardly through `a stufling box in the casing head comprising packing 35, of compressible material held in place by a threaded plug or gland 36. This wire may be raised and lowered by mechanically operated means connected with the upper end 37 at the surface.

In operating this device, the tubing will be installed at the desired depth below the level of. the fluid in the well, so that the pro er load above the piston may be obtained. he packer will be constructed to entirely close od the passage of fluid between the tube and the casing. The iston will then rest upon the support provi ed by the shoe 18 and will be in position above the openings4 17 in the tubing. The valve 33, will be lowered into position to close said openings 17. Air or gas yunder pressure will then be` introduced through inlet pipe 3 and will be forced into the chamber between the tube and casing until the pressurehas reached a predetermined value. This pressure will be sufficient to raise the piston and the load of oil above it. The

valve 33 will then be raised by means of wirel 34 to allow the compressed air or as to enter the openings 17 and lift the piston and its load of oil upwardly to the surface. The bubbles of air will pass lupwardly through the shoe 18, exerting a lifting pressure within the piston, raising it with its load free of said shoe.

When the piston is in its normal position, the dogs 27 will be disengaged from the valve and the spring 24 will hold the valve firmly in its seat. The upward pressure of air will then force the piston and load of oil above i it upwardly to discharge the oil from the pipe 9, after which the piston' will be pro- Jected upwardly into the nipple 8, the pin 23 upon the valve contacting with the stop pin 11, throwing the valve downwardly so that the latching dogs 27 may engage above the head 26 and automatically hold the valve 1n vlowered position so that the pistonmay drop back to its original position upon thesupport 18. After the piston has passed the opening provided by the discharge pipe 9, the compressed air or gas will also be partially exhausted lowering the pressure within the tubing and also to a certain extent within the casing. 'lhe valve may then be dropped quickly to close openings 17 and allow the pressure within the casing to again build up to the desired amount.

When the load of oil has been discharged and the air within the tubing lowered to approximately atmospheric pressure, the oil within thelower end of the tubing will surge upwardly therein to its original position indicated at 38 inthe drawings. The piston will automatically adjust itself to its original p0- sition immediately above the openings 17, the valve 22 closing automatically, and when the pressure has reached the desired amount, a repetition of the previous discharge operation may be performed.

' 1t will be noted that the pressure of air in the casing may be regulated as desired. After the load of fluid above the position is decreased, owing to the lowering of the'oil in the casing may be less than under original conditions when the fluid is higher in the well. As the load above the piston thus gradually decreases, the operation may be accomplished by raising valve 33 whenever the air or gas pressure is sufficient to raise the loadl above the piston. The advantages of this type of de vice liesin the fact .that the load of oil may be discharged abruptly from level in the well, the amount of pressure withl the well with some force so that the sand or sediment will not tend to lodge in the well.

Furthermore, there will be very little wear 4 between the swab piston and the tubing.'

This will be due to the fact that the pressure above and below the piston will be approximately equal therebyovercoming the tendency of the sand and sediment to settle about the piston and cause excessive friction. The action of the discharge of the oil from the well is not materially different from the action of an air gun, each charge of oil being discharged outwardly with some force as the piston is projected upwardly so as to engage the stop pin and throw thel latch and `valve into open position. f

Further advantages of the invention :will be apparent to those skilled in the art Witheout further description. What I claim as new and desire to protect by Letters Patent ISI 1. In a device of the character described,

l space between the casing and tubing, said tubing having openings therein above said packer, a mechanically controlled valve normally closing said openings, a swab piston in said tubing above said openings, means to allow inlet of' compressed air to said easing below said piston to force said piston upwardly,

' land means to allow exit of oil from said tubing. y

2. In a device of the character described, a well casing, atubing in said casing, a-packer in the well closing the space between tubing and casing, said 4tubing having openings therein above said packer, a sleeve valve closing said openings, a swab pistonv in said tubing above said openings, means to allow inlet of compressed air to said casing below said piston to force said piston upwardly' and means to operate said valve for the purpose described. A o

3. In a deviceof the character-described a well casing, a tubing therein, means to close the space between said tubing and casing at the upper end thereof, a packer between said tubing and casing at. a point below the oil level inthe well, 'said tubing having valve controlled openings above said packer, a

' -swab piston in said tubing above said openings and means whereby compressed air may be forced into'said casing to move said piston upwardly in said tubing for the purpose described.

4. A pneumaticA well swab comprising a Y casing,'a tubing therein, means closing the upper .end of said casing, a packer between said tubing and casing below the liquid level in the well, there being openings in said tubing above said packer, a piston in said tubing above said openings, means to allow alr pressure to be exerted 1n said casing and means to control the entrance of air from said casing to said tubing through said openings to move said piston upwardly in 'said tubing to the surface'.

5. A pneumatic well swab comprlsing a casing, a tubing therein, a packer closing the space between said casing and tubing at a point below the liquid level, means closing the upper end of said casing, a piston in said tubing abovelsaid packer and mechanically controlled means o n said tubing ,to admit air piston to move said 'tubingto the surface.

In testimony whereofJI hereunto aix my signature this the 23dday of October, A. D.

under pressure into s aid tubing below saidpiston upwardly in said

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2699121 *Jul 25, 1949Jan 11, 1955Nat Supply CoPlunger lift
US2851954 *Aug 25, 1955Sep 16, 1958Kobe IncCounterflow free pump system
US4596516 *Jul 16, 1984Jun 24, 1986Econolift System, Ltd.Gas lift apparatus having condition responsive gas inlet valve
US4871302 *Jan 26, 1988Oct 3, 1989Milam/Clardy, Inc.Apparatus for removing fluid from the ground and method for same
U.S. Classification417/60
International ClassificationF04B47/00, F04B47/12
Cooperative ClassificationF04B47/12
European ClassificationF04B47/12