US2426164A

US2426164A - Cementing tool for oil wells

Info

Publication number: US2426164A
Application number: US516009A
Authority: US
Inventors: Christian W Breukelman
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-12-29
Filing date: 1943-12-29
Publication date: 1947-08-26
Anticipated expiration: 1964-08-26

Description

2 Sheets-Sheet l INVENTOR ATTORNEY,

wd??- c. w. BREUKELMAN CEMENTING TOOL FOB. OILWELLS Filed Deo. 29, 1945 Fr G. 2

WHR/5 Tm /v WBREz//fa MA /v Flai Aug- 25, 1947- c. w. BREUKELMAN 2,426,164

CEMENTING' TOOL FOR OIL WELLS Filed Dec; 29, 194s 2 Sheets-Sheetl 2 UHR/s ruw WERE/EL MA /V INVENTOR 4W mw ATTO R N EY Patented Aug. 26, 1947 UNI-TED CEMENTING TooL Fon oIL WELLS Christian W. Brcukelman, Trinidad, British West Indies Application December 29, 194:3, Serial No. 516,069

3 Claims. l.

My invention relates to cementing tools for oil wells and' has particular reference to tools forl sealing perforations in casing pipes in oil wells.

My invention relates to cementing tools for oilwells, and has particular reference to tools for forcing cement through perforations in casing pipes and sealing them;

Perforations are sometimes providedA in oil well casings within a limited vertical space, usually a few feet, to provide a passage through which cement slurry can be forced into the annulus outside the casing to prevent the movement of fluids such as gas, oil, or water behind the casing.

Similar perforations are sometimes provided for admitting oil or gas into the well, and occasionally it becomes necessary to seal such perforations as, for instance, when they lead into dry formations or formations containing salt water, etc. The usual method of sealing the perforations is by means of cement which is forced into the holes by a special tool.

Ordinary tools used for cementing holes in the casing pipes have a disadvantage in that they employ complicated valves requiring. rotation of the tool, special slips, etc.

My invention has for its object to providey a cementing tool in which all the operations for opening and closing cement-admitting ports, can be effected by the simple procedure of lowering and raising the tool, the vertical movement of the tool being used to operate sliding frictional sleeves or valves for opening and closing" different ports or openings.

Another object of my invention is to provide means in my tool for using the same for .washing out the excess cement after completion of the cementing operation.

Still another object of my invention is to provide a single tool which can be used for cementing' and washing out operations under all operating conditions, and particularly those in which it is undesirable to exert additional pressure on the well below the tool during these operations.

My invention is more fully described in the accompanying specication and drawings in which:

Fig. 1 is a fractional sectional view of a well casing with my tool in position of being lowered into a casing pipe;

Fig. 2 is a similar View of mytool after it has been slightly raised to move sliding Valves for opening ports;

Fig. 3 is a fractional sectional Viewv of a modied tool;

2 Fig. 5 is a sectional view of a modified bottom valve;

Fig. (i is a similar View oi another modification;

Figs. 6 to 11 are views of a modilied toolv in different stages of operation.

My cementing tool consists of a tubing I made in several sections connected together by threaded

couplings

22, 23, 24, 25.

The tubing is of a substantially smaller diameter than the inside diameter of a Casing pipe 3 forming walls of a well. The tubing I is provided in the middle with an inner tube a whose upper flared-out end 2 is welded to the inner walls of the tubing I, the lower end of the inner tube being closed at `5. Short tubes or ducts 6 connect the lower portion ofthe tube 4 with the annular space I between the tube 4 and casing 3*. Sealing cups or swabs 8, 9 are placed on the tubing I at either side of the ducts `l. The swabs are made of an elastic material such as rubber. The cups are of a larger diameter than the casing pipe and are resiliently forced into the casing pipe, forming water-tight seal. They are placed opposite each other as shown so that they effectively resist any pressure which may be applied to the annular space I between them. The swabs or cups are placed at a distance of few feet from each other or substantially farther apart than the maximum distance between the extremeV outer perforations or shot-holes I0 in the casing pipe.

The tubing I is also provided with vent holes II below the ilared top portion of the inner tube 4, which holes are open at all times. The tubing I is also provided with upper vent holes or ports I2 and lower ports I3 which can be closed by slidf ing sleeves or valves I4 and I5 respectively, slidably mounted on tubing I. The sleeves are of a larger diameter than the tubing I, the annular space in the sleeves being filled with chevron o-r similar packing Il of self-sealing type, held at the ends of the sleeves by threaded annular caps or flanges I8. Spring clamps I9 are fastened to the sleeves and frictionally engage the inner walls of the casing 3.

Springs I9 bear on the inner wall of the casing with suicient pressure to hold the sleeves I4, l5 to which they are attached in the stationary position when tubing I is moved up or down, sliding through the sleeves, until one or the other of the

couplings

22, 23, 24, and 25 engage the corresponding sleeve, whereupon the sleeve will be moved together with the tubing in a corresponding direction. Thus, when the tubing I is moved downward, sleeves I4 and I5, being engaged by the

couplings

22 and 24 respectively, will be brought to their upper operative positions as shown in Fig. 1, closing ports I2 and I3. Oil or other fluid in the well will be forced upward past a lower ball valve 2U into the tubing I, into an annular space 5 within tubing I surrounding tube 4, and out through holes II into the annular space 1, bypassing swabs 8, 9.

After the tool is placed in position, the next operation consists in forcing the uid out of the space 1' between the swabs 8, 9. This is accomplished by pumping water into the tubing I for determining the break-down pressure, or pressure at which the liquid begins to ow into the holes I3. Ports I2 are closed during this operation. The tubing, as far down as the top of the tool, is then filled or partly filled with cement slurry. The tubing for this purpose is slightly raised, just sufficiently to open ports I2. Slurry is then pumped down the tubing, the return circulation passing through ports I2 into the annular space 1 in the casing pipe. It should be noted that the port I2 must be opened, to avoid having to pump all of the iiuid in the tubing ahead of the cement through holes I3 into the formation. The position of sleeve I5 during this operation is as a rule immaterial, but port I3 can be closed if desired and port I2 opened by suitable movements of the tool.

The next operation is the pressure or squeeze cementing. The tubing I is lowered, closing the ports I 2. Slurry is pumped into the tubing under pressure, forcing it through the inner tube 4 and through ducts 6 into the space 1 between the swabs 8, S. Under continuous break-down pressure, cement slurry is forced from the space 1 and through shot holes I into the space outside the casing. IThe pressure is held until no back iiow is observed, i. e., until cement is sufficiently set. In some instances, as in multiple-stage cementing, valved cementing ports are inserted in, and form part of the casing pipe at pre-selected points. These valves prevent back-flow of cement slurry, and the tool can be withdrawn immediately after the cement is placed behind the casing.

It should be noted that the movement of sliding sleeve valves I4 and I5 is limited by the

couplings

22, 23 which limit movement of the sleeve I4, and 24, 25 which limit movement of the sleeve I5. The upper ports I2 are closer to the upper coupling 22 than the lower ports I3 are to the coupling 24 so that it is possible to raise the tubing I just enough to uncover the upper ports I2 without uncovering the lower ports I3.

The ball 23 is supported in a cup-shaped expanded upper end 26 of a tube 2l, sliding in a tubular casing 28 supported at the lower end of the tubing I. The upward movement of the tube 21 is limited by the coupling 25 to which the casing 28 is attached, the downward movement being limited by a flange 29 with a central opening for the tube 21 and also holes 3i) therein. The depending end of the tube 21 is provided with springs 3I frictionally engaging the inner wall of the casing pipe 3. A sealing cup-shaped member or swab 32 is tted on tube 21 below the cup 26, preventing fluids in the tubing I from penetrating below the tool.

As shown in Fig. 1, the tube 21 with the ball valve 20 is brought to the top of the casing 28 by the downward movement of the tool because of the friction of the springs 3| against the walls of the casing pipe 3. The tube 21 is lowered again relative to the tubing when the tool is raised for opening the port I 3, and that no suction or swabbing is produced below the too-l during this operation. The valve I uncovers the ports I3 thereby equalizing pressure at both sides of the swabs 8, 9 and preventing formation of vacuum or suction under the tool. Port I2 offers no problem when raising the tool, because port II is always open. If port I3 is closed, when the tool is raised, swab 9 comes into action, fiuid pressure is exerted on ball 20 through ports II, tube 21 must then move down in casing 23, and swabbing action is prevented while port I3 is being uncovered.

A retrieving spring may be provided for the tube 21 as shown in Fig. 5 so as to keep the valve 2B raised except when the tool is being withdrawn from the casing pipe.

Upon completion of the cementing operation, the excess cement is washed out from the inside of the tool. The tool for this purpose is raised above the perforations I3 (or above any, still higher, perforations, to avoid loss of washing fluid), the upward movement of the ytool will leave valves I4 and I5 resting on the

couplings

23 and 25 respectively, uncovering ports I2 and I3 respectively. These ports must be closed for the washing operation, and this can be accomplished by lowering the tool just enough to bring the ports I2, I3 under the respective valves I4, I5. Water is then pumped down the casing pipe, past upper or inverted swab 8, through the openings 6 and up the inner tube ll into the tubing I. Since both ports I2 and I3 are closed during this operation, no pressure will be exerted on the well below the tool. It should be noted that duct 6 is placed as far as possible from swab 8, so that the maximum washing of annulus 1 is effected.

The sliding tube 21 materially facilitates operation of the device, making it easy to pull the tool even out of deep holes.

If desired, if open formations exist below the tool, and there is no objection to slight swabbing or suction action while opening the ports I3, the sliding valve tulbe 21 may be dispensed with and a standing valve 34, Fig. 4, may be used.

The tool can -be also used for circulating a liquid down the tubing I and up the casing 3, without exerting pressure on the well below the tubing. The tool for this purpose is lowered to close the ports I2 and I3 by the valves I4 and I5, then raised suiciently to close the ports I3 but not I2, as shown in Fig. 2. This is possible because the port I3 is located at a greater distance from the coupling 24 than the port I2 from the coupling 22 so that a small upward displacement of the tubing I is suicient for uncovering the port I2 while leaving the port I3 still closed. The ports I3 being closed, no liquid can penetrate into the space under the swab 9, the return liquid iiowing up the casing 3.

If it is desired to wash out excess cement from between the swabs 8 and 9, and then circulate it out up the casing 3, it is necessary rst of all to close ports I2 and I3 and pump down the casing and up the tubing past swab 8 by a method already described. Then, when the cement has been brought into the lower part of the tubing I, port I2 is opened as described in the previous paragraph, leaving port I3 closed, and the cement is displaced up the casing 3 by pumping down the tubing.

My tool can also replace two cement retainers, one below the shot holes as a bridge plug, and the other above for squeeze cementing.

My tool can be used for various other purposes, such as acidizing oil wells, injecting chemicals under pressure, or for perforation washing.

A modified tool is shown in Fig. 3, specially adapted for high pressure cementing. It isf provided with two swabs 36, 31- at the top, facing in the opposite directions and of a heavy pressure type. A similar heavy pressure swab 38' is placed below eementing region 'Il'. Ports 40 are also provided with lapper valves 4I for washing out the excess cement. Water or other liquid for this purpose is pumped down the casing annulus 1,

through the upper port II, into the tubing I, out the valved ports 4I, in-tothe cementing region 1', andi back through ports 6= and tubing 4 and I'. The val-ve 4I may be' dispensed with for medium pressures as shown in Fig. 4, using more

flexible swabs

42, 43, 44 and 45.v

The ports 4E are located between

thelower swabs

44, 45 without any valves.

Distance between the upper and lower swabs can be adjusted. by inserting pieces 41 of varying length between the couplings in the tubing in the cementing region.

A modified tool is shown in Figs. 6 to 11. In this tool the ports I2 and I3 are at the same distance from the collars 22 and 24l but the distance between the upper collars 2-3 and 22 is considerably greater than the distance between the lower collars 24 and 25:.

Position of the tool during its being lowered into the well is shown in Fig. 6. The valves I4 and I5 are moved upward, resting against the

collars

22 and 24 respectively, closing both ports. When the tool is lowered to a` point in which the holes Ill in the casing 3 are placed between the swabs 8 and 9, the breakdown pressure is determined by pumping a liquid through the inner tube IV and noting the pressure at which the liquid begins to flow into the formation through the holes I0. The tool is then raised as shown in Fig. 7 to uncover the port I2. Enough of the cement solution is then pumped into theinner tube for driving the liquid ahead of the solution upward through the port I2 and through the annular space in the casing 3. The tool is now ready for cementing operation. I-t is lowered again as shown in Fig. 8 for closing the ports, and more cement is pumped into the inner tube I forcing the cement at the breakdown pressure into the formation through the holes I between the swabs.

Upon completion of the cementing operation the tool is raised above the cemented area as shown in Fig. 9.

During this raising operation the liquid from above the tool ows downward through the ports I2, I I, space and port I3 so that no vacuum is formed under the tool.

For washing out the cement from the tool, the latter is lowered as shown in Fig. 10 for closing the valves. The lowering is possible without creating pressure under the tool because the liquid from under` the tool flows upward through the ball valve at the bottom and through the open ports II. With both ports I2 and I3 closed as shown in Fig. 11, and with the swabs 8 and 9 above the cemented area, a liquid is pumped into the outer annular space 1, pressure of the liquid causing the upper swab 8 to collapse, admitting the liquid into the space between the swabs, from which it flows upward through the tubes 6, 4 and I. The upper swab acts as a valve in this case, being of a convex shape.

It should be noted that the packing in the valve I4 must resist pressure from within and from without the valve, while the packing in the valve I5 must resist onlypressure from within the tool.

It is understood that my cementing tools for Cil `oil Wells may be further modified without` de,-

parting from the spirit of the invention, as set forth in the appended claims.

I claim as my invention:

1. A cementing tool for oil wells` comprising a tubing constructed to be placed in a casing of a well, the tubing being of a substantially smaller diameter than the casing; a tubular member of a still smaller diameter within the tubing, the upper end of the tubular member communicating with the tubing and being narod-out and attached to the inner wall of the tubing, forming a seal between the tubular member and the tubing; a checkY Valve closing the lower end of the tubing against downward ow of huid; the lower end of the tubular member being closed to communication with the tubing; tubular ducts connecting the tubular member with the outside of the-tuk ing; sealing swabs on the tubing above and below the outer openings of the tubular ducts, said swabs being spaced apart a distance greaterthan the length of that portion of the .casing occupied by holes to be cemented; the tubing having permanently open ports abovethe sealing swabs and below the flared-outl end of the tubular member, and having additional ports above and below the sealing swabs; sleeves slidably supported on the tubing for closing said additional ports; frictional members extending from the sleeves and engaging the inner wall of the casing forretaining the sleeves stationary when the tubing is moved; the said additional ports above th swabs being also above the flared-out end of the tubular member, the sleeves being adapted to close said additional ports when the tubing is moved downwardly, and to open said additional ports when the tubing is moved upwardly; an enlarged tube depending from thelowerend of the tubing; a sliding tube in the enlarged tube and extending through the lower end of the enlarged tube; a sealing swab at the upper end of the sliding tube engaging the inside walls of the enlarged tube; means on the outwardly extending portion of the sliding tube for frictionally engaging the inner surface of the casing; and means to limit the movements of the sliding tube in the enlarged tube, the distance of movement of the sliding tube being comparable to the distance of movement of the tubing for opening the ports, the check valve being arranged to be opened by inwardly flowing well huid when lowering the tool for admitting the fluid from the well into the tubing, the well uid flowing outwardly through said permanently open ports into the casing.

2. A `cementing tool for oil wells comprising a tubing constructed to be placed in a casing of a well, the tubing being of a substantially smaller diameter than the casing; a tubular member of a still smaller diameter within the tubing, the upper end of the tubular member communicating with the tubing and being flared-out and attached to the inner wall of the tubing, forming a seal between the tubular member and the tubing; tubular ducts connecting the tubular member with the outside of the tubing, sealing swabs on the tubing above and below the outer openings of the tubular ducts; said sealing swabs being spaced apart a distance .corresponding to the length of that portion of the casing occupied by holes to be cemented; the tubing having permanently open ports above the sealing swabs and below the flared-out end of the tubular member, and having additional ports .above and below the sealing swabs, the additional port above the swabs being also above the flared-out end of the tubular member; sleeves slidably supported on the tubing for closing said additional ports; frictional members extending from the sleeves to the inner wall of the casing for retaining the sleeves stationary when the tubing is moved; an enlarged tube depending from the lower end of the tubing; a sliding tube in the enlarged tube and' extending through the lower end of the enlarged tube; a sealing swab at the upper end of the sliding tube engaging the sides of the enlarged tube; an upwardly and downwardly closing check valve at lthe upper` end of the sliding tube for preventing downward flow of the iluids through the tubing; frictional means on the outward extension of the sliding tube for engaging the inner surface of the casing; and means to limit the movements of the sliding tube in the enlarged tube.

. 3. A cementing tool for oil Wells comprising a tubing constructed to be placed in a casing of a wall, the tubing being of a substantially smaller diameter than the casing; a tubular member of a still smaller diameter within the tubing, the upper end of the tubular member communicating with the tubing and being flared out and attached to fthe inner wall of the tubing, forming a seal between .the tubular member and the tubing, tubular ducts connecting the closed end of the tubular member with the space outside of the tubing; sealing swabs on the tubing above and below the outer openings of the tubular ducts for sealing off an annular space in the casing between the ca-sing and tubing above and below the lower end of the tubular member, said swabs being spaced apart a distance greater than the length `of the portion of the veasing occupied by holes to be cemented; the tubing having permanently open ports above and sealing swabs under the enlarged end of the tubular member and additional ports above the open ports and below the 8 lower swabs respectively, the additional upper port being above the flared out end of the tubular member; sleeves slidably supported on the tubing for closing the upper and lower additional ports respectively; frictional members extending from the sleeves to the inner Walls of the casing for retaining the sleeves stationary when the tubing is moved; upper collars on the tubing above the additional ports for engaging the sleeves when fthe tubing is moved downwardly in which position of the sleeves the additional ports are closed by the sleeves; lower collars on the tubing below the additional ports and spaced therefrom'for engaging the sleeves when the tubing is moved upwardly in which position of the sleeves the additional ports are opened, the distance between the upper and lower collars on that portion of the tubing above the swabs being greater than the distance between the collars below the swabs for enabling the lower additional ports to be closed ahead of the upper additional ports when the tubing is moved upwardly; and means including a downwardly closing check valve at the bottom of the tubing, for admitting a fluid from the well into the casing through permanently open ports when the tool is being lowered.

CHRISTIAN W. BREUKELMAN.

REFERENCES CITED The following references are of record. in the ille of this patent:

UNITED STATES PATENTS Number Name Date 2,341,832 Verheul et al Feb. 15, 1944 2,235,318 Halliburton Mar. 18, 1941 2,308,072 Granger Jan. 12, 1943 2,214,121 Coste1lo Sept. 10, 1940 2,360,311 Ausburn et al Oct. 1'7, 1944