US2650546A - Swab for tapered casing or tubing - Google Patents

Description

P 1, 1953 H. J. PANKRATZ 2,650,546

SWAB FOR TAPERED CASING OR TUBING 4. M M gi/III I w I n I 24 32 W9 I. "H216 4 i 2 9 I] 9 34 I a, z 33' I" I I H! I fifi .0 I' 53 Mill/ FIG.

ATTORNEYS Sept. 1, 1953 H. J. PANKRATZ 2,650,546

SWAB FOR TAPERED CASING 0R TUBING Original Filed March 11, 1947 3 Sheets-Sheet 2 P 1953 H. J. PANKRATZ 2,650,546

SWAB FOR TAPERED CASING OR TUBING Original Filed March 11, 1947 3 Sheets-Sheet 5 I I l fi I47 ll35 41H 6 H. j fl fiz FIG. .9 BY

mm 1* m ATTORNEYS Patented Sept. 1, 1953 SWAB FOR TAPERED CASING OR TUBING Howard J. Pankratz, Bartlesville, 0kla., assignor to Phillips Petroleum Company, a corporation of Delaware Original application March 11, 1947, Serial No.

Divided and this application March 23, 1951, Serial No. 217,239

8 Claims.

This invention relates to swabs. In one specific aspect it relates to swabs which are self adjustable to fit and operate properly in a plurality of dimensions of pipe such as the casing or tubing of a well.

This application is a division of my copending application Serial No. 733,881, filed March 11, 1917, now Patent No. 2,623,473 dated December 30, 1952, for Swab for Tapered Casing or Tubing, and the claims herein are directed to that species of the invention shown in Figure 1 thereof.

Inmodern practice in deep wells, it is advantageous and economical to use tapered strings of casing and tapered strings of tubing, with thinner tubing or casing for the center portion of the well and increasing the thickness of the walls of the casing or tubing toward the top and bottom of the well. In inserting tubing and casing in a well it is suspended from the derrick in a long string thousands of feet in length and the center portion of the string need not be as strong as the upper portion, which is supporting the lower portion, or as strong as the bottom portion which must withstand the hydrostatic collapse pressure. By making the lower portion lighter, the upper portion has less to support. The only .disad vantage of i this system is that theinside di: ameter of the tubing or casing varies from small to large and back to small "again as a swab travels up the well and the swab must adjust itself to the change in diameter. The tapering of the tubing is generally notuniform, but usually consists of running several hundred feet of a certain thickness, and then running a similar 5 number of the next thickness, and then the next thickness, etc., until sufiicient tubing or casing has been assembled.

During the life of a well it is often necessary toswab the same either as a simple pumping op eration, or for other purposes such as causing pressure changes on the formation 'to stimulate natural flow,or simply to remove liquids 'or mud from the well.

While satisfactory swabs have been produced which will work with high efiiciency for long periods of time in a single internal diameter size of tubing or casing, these swabs have proved inemcient, or inoperative, or have rapidly broken down when used with tapered casing or with tubing having .a plurality of, internal diameters.

One object of the present invention is to provide an improved swab.

Another object'is to provide a simple and easily operated swab having a minimum number of parts which are inexpensive to build and rugged,

in operation.

Another object is to provide a swab which will operate in a casing or tubing having a plurality of inside diameters.

Another object is to provide a swab which will automatically adjust itself to a wide variation in internal diameters of a pipe through which it is being pulled.

Another object is to provide a swab which uses the hydrostatic head of the liquid being lifted to seal the swab to the pipe.

Another object is to provide a swab which can be collapsed for easy removal upon dropping a Weight.

Another object is to provide a swab which can be collapsed for easy removal by operation of a time f clock.

Another object is to provide a swab which is inflatable by a self contained source of gas under high pressure.

Numerous other objects and advantages will be apparent to those skilled in the art upon reading the accompanying specifications, claims and drawings.

In the drawings:

Figure 1 is a cross sectional view with parts broken away of a swab embodying the present invention.

Figure 2 is a similar view of a second modified swab embodying the invention.

Figure 3 is a similar view of a third modified swab embodying the invention.

Figures 1, 2 and 3 show onlyv a portion of the swab, the longitudinal axis of the swab running longitudinally of the figures right through the center of the large balls shown therein. As most of the elements of the swab are volumes of revolution generated around that axis, it is believed that illustration of the broken away portion of the swab is unnecessary.

, In-Figure 1, a swab generally designated as 4 is designed for operationin pipe of varying di ameter in awell for swabbing liquid from said well. Swab 4 comprises a first supporting member 6 which is preferably made in two parts 6 and I in order to allow access to the interior thereof. At8 threads are provided for connection with a cable or tubing by which the swab is raised or lowered in the well.

A second supporting member 9 is provided at telescopic relationship with said first member 6, and said member 9 is preferably made in several pieces, namely, body parts 9 and I0, plug II and cap l2. Cap I2 is provided with holes l3 and 3 acts to push washer I4. Plug I is provided with a passage I6 communicating with passage I1 in the interior of 9 and through passages I3 with passage I8 in the interior of 6 and then through passage I9 to the exterior of the swab. Passages I9, |8, I3, I1 and I6 form a by-pass passage around the swab 4 and flow therethrough is controlled by an upwardly opening check valve 2|.

When the swab is first inserted in the well, washer I4 is held above frangible pin 22, but in the position shown in Figure I, frangible pin 22 has been broken and the broken off portion 23 has fallen to rest on shoulder 24 of member 6.

Member 9 is provided with outstanding ears 26 to which arms 21 and 28 are pivoted by pivot pins 29 and 3| respectively. 7

Arms 21 and 28 have curved cam surfaces 32 and 33 respectively to engage rubber cup 34 and extend the same out to the tubing which is of varying diameter.

Cup 34 rests on flange 36 of member I8 and has a sealing flange 31 provided to prevent leakage. Cup 34 is held down by shoulder 38 which is spring pressed by spring 39. The upper edge of cup 34 is turned inward at 4| and is preferably secured to some form of retaining means such as ring 42 by means of such securing means as bolt 43 and nut 44. Ring 42 is provided with i fles 46 and fits loosely around member 6 at Arm 21 may be provided with a cut away portion 48, if desired, as such cut away portion gives better action to the arm. Arm 21 is pivoted on member 9 at 29 and in effect is pivoted on member 6 at 49. While only one set of arm 21 may be used if desired it is preferred to have at least another set of arms such as 28. As many sets of arms as desired may be provided, each set being separated by a spacing sleeve I and urged apart by a spacing spring 52. The lower set of arms 28 is supported by a spring 39 and support member 53.

Inside of sleeve 5I is provided a space 54 and inside of cup 34 is a space 55 for the collection of liquid in the swabbing of the well as such liquid tends to expand cup 34 into sealing engagement with the well pipe.

In Figure 2, a modified form of swab, generally designated as 6|, is shown having a supporting member 62 which is provided with means 63 at its upper end for connection to a cable or string of pine by which said swab is operated upwardly and downwardly in the well.

Member 62 is provided .with a central by-pass passage 64 communicating with the well through holes 66 above packer 61 and through hole 68 in plug 69 below packer 61. Flow through this bypass passage is controlled by the upwardly openin check valve H. Member 62 is provided with u er flan e 12 and a lower flange or washer 13. Between flanges 12 and 13 are located the operat n portions of the packer.

Packer 61 consists of an annular rubber tube or casing very much like an automobile tire in which is disposed an inflatable inner tube 14, which will expand into space 16 when as under sufficient pressure is placed in space 11.

A chamber 18 is provided having a gas space 19 containing sufficient gas under sufficient pressure to inflate tube 14 and press casing 61 firmly against the wall of the well pipe, regardless of the diameter of the ipe. As the pine decreases in diameter. part 61 will be correspondingly deformed and the air in 11 correspondingly compressed.

In order to connect space 19 with 11 a conduit 8| is provided connecting the two. Conduit 8| is controlled by an upwardly opening spring check valve 82 and a downwardly opening spring valve 83. Valve 83 is adapted to be compressed by arm 84 when body 86 is moved downwardly, conduit BI being flexible at point 81 to allow for such movement. When the device is inserted in r the well a flexible pin 88 holds conduit 8| in extended position. When flexible pin 88 is broken, however, due to the weight of liquid above 61, flexible pin 88 becomes broken and valve 83 is forced open.

Conduit 8| may be made up in a large number of ways and may comprise various nipples 89, 9| and 92 and thimbles 93 and 94. Nipple 92 contains valve 96 which may be open by contact of plate 91 with head 98. Plate 91 ordinarily cannot contact head 98 because springs 99 guided on pin IIlI holds 91 spaced from top plate I02.

The flexible tube assembly 61 includes top plate H12 and lower plate 86 along with intermediate plates I03 and I84 held together by bolt I06. These plates allow the assembly of the device Which otherwise would be hard to assemble, as conduit 8| has a branch I01 connecting to tube 14 by the usual connecting means I08 and I89.

A go-devil tube III is provided with a tapered surface Hz to avoid contact with flange I92. Go-devil III is dropped into the well to open the valve by plate 91 contacting valve 98 by compressing spring 99 when desired.

In Figure 3, a third type of swab, generally designated as H3, is shown. This swab is built into a single body composed of upper member 4 having threads or other means of connection II6 for connecting the same to a cable or operating tubing (not shown). Member 4 is screw threaded to sleeve II1 which in turn is closed by plug II8 having a passage II9 therethrough controlled by upwardly opening check valve I2I. A by-pass conduit is provided at I22 in sleeve II1 with passages I23 below the packer casing I24 and passages I26 above the packer casing for passage of liquid around the casing.

Casing I 24 is similar to an automobile tire casing and tube I21 is similar to an automobile inner tube. A guide plate I28 is provided for guiding the upper part of casing I24 and a lower flange I29 on body II 1 guides the lower portion of the casing. A removable annular member or rim |3| is provided to enable the tires I24 and I21 to be disassembled.

When gas under pressure blows into chamber I32 inside tube I21, it forces tube I21 to expand through space I33 into contact with tube I 24. The lower part of H1 is threaded to receive the lower body portions I34 and I35. Body portion I35 contains enough as in I36 and enough pressure to actuate the inflation of tube I21. A time clock |31 in I34 mav be wound up by winder I38 and shaft I39. The clock is supported by arms I 9 and drives shaft I4I carryin cam I42. Cam I42 has two ro ections I43 and I44 respecti ely thereon. Proiection I43 engages a. valve I46 to allow gas to escape from space I41 and pro ection I44 engages valve I49 to allow as to ex and from space I36 into s ace I41. Gas in I41 passes throu h passa es I49, I5I and I52 into space I 32. The usual connecting means I53, I 54 and 56 may be provided.

Operation of Figure 1 In the apparatus of Figure 1. part 1 is removed from part 6 and part 9 is raised up until a new i'rangible pin 22 can be below washer I4. I is then replaced in 6 and pin 22 will hold V9 in the position where arms 21 and 28 are drawn back out of positive contact with cup 34 (although cup 34 can be pushed back against the arms even in this position).

The swab 4 is then inserted in the well and lowered down through the liquid. While air or gas is in the well this gas will lift ball 2| from time to time and force up through openings I6 and out through openings I9. When liquid encountered, liquid will flow in opening I6, lift ball 2| and pass through openings I3 and I3.

When swab 4 has reached the desired predetermined lower position its motion is reversed and it is raised. Upon raising liquid flows through I9 and I3 and places ball H on seat II. Some liquid will escape around the outside between cup 34 and the wall of the well pipe but this will not occur very long because most of the liquid transmits pressure through opening 46 to space 55 throwing considerable weight on flange 36 which breaks frangible pin 22. Member 6 moves upwardly relative to member 8 into a position somewhat the same as shown in Figure 1.. Arms 21 and 28 rotate and push the walls of cup 34 out into sealing relationship with the well pipe I (not shown). As the well pipe increases and decreases in diameter arms 21 and 28 will move upwardly and downwardly about pivots 29 and 3| accommodating for the change in the size of pipe. Upon reaching the top of the well a new pin 22 needs to be inserted below washer I 4 as described above and this cycle is then repeated.

Operation of Figure 2 Threads 63 are engaged with the cable or pipe in the same manner as threads 8 were in Figure 1, pin 88 being in place and tire I4 being dedated. Part III has not been employed as yet and should be disregarded for the moment. The swab BI is inserted into the well and on the downward trip gas or liquid comes in opening 68 pushing back ball II and passes through 64 and out hole 66 above packer 61. Liquid flowing past 61 tends to support the same. Upon reaching the predetermined low point in the well the motion is reversed and the swab BI is hoisted by the means attached at 63. Liquid closes valve II immediately and while someesoapes around the outside of packer 61 the plate I02 is soon loaded with enough weight to break frangible pin 88. Upon this happening, plate 86 and all related parts move downwardly so that pin 84 opens valve 83. Gas in It then rushes up conduit 8] into space TI expanding packer I6 into engagement with the wall of the pipe. If the pipe varies in diameter 5'5 will move inward or outward to actuate itself.

If through some trouble, the swab should become stuck in the well and it is desired to remove the same with as little effort as possible a godevil pipe III is dropped down into the well where it strikes plate 9'! and forces this plate to compress spring 99 and contact valve 98 allowing gas in 1! to bleed oil through nipple 92 allowing packer 61 to collapse. The swab is then very easily removed.

Operation of Figure 3 Figure 3 operates much the same as Figure 2 except that the inflation of packer I24 is controlled by time clock I31. The time clock is wound up with the parts in the position shown and with packer I24 collapsed. Part H6 is secured to the usual operating means consisting of a cable or tubing (not shown). The swab H3 is put into the well and .run down to the desired position, .any fluid in the well passing through I23, I22, and I19 opening valve I2I and passing out opening I26.

When a sufficient time has passed to allow the swab to be positioned properly, clock 13'! rotates cam I42 until projection I44 opens valve I48. Gas from 136 passes through I48 and spaces I41 into passage I49 leading through passages I5I and I52 into space I32 in inner tube I21. Pack-er 12s is thus inflated.

The swab is drawn upwardly and packer I24 adjusts itself to the different diameter of the pipe.

If the swab II3 becomes stuck for any reason the operator need only wait until cam I42 rotates until projection I43 contacts I46 and opens the same, whereupon the pressure in tube I32 bleeds out through passages I52, I5I, I49 and space I 41, whereupon packer I24 collapses and swab H3 is easily removed from the well.

Numerous conventional changes in size, shape or arrangement of parts may obviously be made without departing from the spirit and substance of the present invention as defined in the claims,

Having described my invention, I claim:

1. A swab for operation in pipe of varying diameter in a well for swabbing liquid from said well comprising in combination a first supporting member, a second supporting member in telescopic relationship with said first member, an open top rubber cup supported on said second member, said first and second members being formed with a. connecting by-pass passage communicating with said well above and below said cup, an upwardly opening check valve controlling flow of said liquid through said by-pass passage, arms pivoted to one of said members and guided during resulting pivoting movement about said pivots during telescopic movement between said members by engagement with a portion of said other member, said arms having cam surfaces disposed upon untelescoping movement of said members to move into expanding engagement with said cup, frangible means holding said members in telescoped relation and said cam surfaces of said arms out of expanding contact with said cup until broken upon raising said swat, in said liquid by the weight of liquid above said cup, and spring means urging said arms into engagement with said cup.

2. A swab for operation in pipe of varying diameter in a well for swabbing liquid from said well comprising in combination a first supporting member, a second supporting member in telescopic relationship with said first member, any

open top rubber cup supported on said second member. arms pivoted to one of said members and guided during resulting pivoting movement about said pivots during telescopic movement between said members by engagement with a por tion of said other member, said arms having cam surfaces disposed upon untelescoping movement of said members to move into expanding engagement with said cup, frangible means holding said members in telescoped relation and said cam surfaces of said arms out of expanding contact with said cup until broken upon raising said swab in said liquid by the weight of liquid above said cup, and spring means urging said arms into engagement with said cup.

3. A swab for operation in pipe of varying diameter in a well for swabbing liquid from said well comprising in combination a first supporting member, a second supporting member in telescopic relationship with said first member, an open top rubber cup supported on said second member, said first and second members being formed with a connecting by-pass passage communicating with said well above and below said cup, an upwardly opening check valve controlling flow of said liquid through said by-pass passage, arms pivoted to one of said members and guided during resulting pivoting movement about said pivots during telescopic movement between said members by engagement with a portion of said other member, said arms having cam surfaces disposed upon untelescoping movement of said members to move into expanding engagement with said cup, and spring means urging said arms into engagement with said cup.

4. A swab for operation in pipe of varying diameter in a well for swabbing liquid from said well comprising in combination a first supporting H member, a second supporting member in telescopic relationship with said first member, an open top rubber cup supported on said second member, said first and second members being formed with a connecting by-pass passage communicating with said well above and below said cup, an upwardly opening check valve controlling flow of said liquid through said by-pass passage, arms pivoted to one of said members and guided during resulting pivoting movement about said pivots during telescopic movement between said members by engagement with a portion of said other member, said arms having cam surfaces disposed upon untelescoping movement of said members to move into expanding engagement with said cup, frangible means holding said members in telescoped relation and said cam surfaces of said arms out of expanding contact with said cup until broken upon raising said swab in said liquid by the weight of liquid above said cup and means biasing said arms into engagement with said portion of said other member.

5. A swab for operation in pipe of varying diameter in a well for swabbing liquid from said well comprising in combination a first support- QC ing member, a second supporting member in telescopic relationship with said first member, an open top rubber cup supported on said second member, arms pivoted to one of said members and guided during resulting pivoting movement 8 an open top rubber cup supported on said second member, arms pivoted to one of said members and guided during resulting pivoting movement about said pivots during telescopic movement between said members by engagement with a portion of said other member, said arms having cam surfaces disposed upon untelescoping movement of said members to move into expanding engagement with said cup, frangible means holding said members in telescoped relation and said cam surfaces of said arms out of expanding contact with said cup until broken upon raising said swab in said liquid by the weight of liquid above said cup and means biasing said arms into engagement with said portion of said other member,

- scopic relationship with said first member, an

open top rubber cup supported on said second member; said first and second members being formed with a connecting by-passage communicatin'g with said well above and below said cup, an upwardly opening check valve controlling flow of said liquid through said by-pass passage, arms pivoted to one of said members and guided during resulting pivoting movement about said pivots during telescopic movement between said members by engagement with a portion of said other member, said arms having cam surfaces disposed upon untelescoping movement of said members to move into expanding engagement with said cup and means biasing said arms into engagement with said portion of said other member.

8. A swab for operation in pipe of varying diameter in a well for swabbing liquid from said well comprising in combination a first supporting member, a second supporting member in telescopic relationship with said first member, an open top rubber cup supported on said sec-- ond member, arms pivoted to one of said members and guided during resulting pivoting movement about said pivots during telescopic movement between said members by engagement with a portion of said other member, said arms having cam surfaces disposed upon untelescoping movement of said members to move into expanding engagement with said cup and means biasing said arms into engagement with said portion of said other member.

HOWARD J. PAN KRATZ.

References Cited in the file of this patent UNITED STATES PATENTS Humason et al Feb. 25, 1941

Images