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Publication numberUS2638165 A
Publication typeGrant
Publication dateMay 12, 1953
Filing dateJan 24, 1948
Priority dateJan 24, 1948
Publication numberUS 2638165 A, US 2638165A, US-A-2638165, US2638165 A, US2638165A
InventorsBarber Louis D
Original AssigneeBarber Louis D
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Well perforator
US 2638165 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

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L D BARBER WELL PERFORATOR May 12, 1953 Filed Jain. 24, 1948 May 12, 1953 L. D. BARBER 2,638,165

WELL PERFORATOR Filed Jan. 24, 1948 2 Sheets-Sheet 2 firioww Patented May 12, 1953 UNITE STATES PATENT OFFICE WELL PERFORATOR Louis D. Barber, Burbank, Calif.

Application January 24, 1948, Serial No. 4,185

During the drilling of relatively deep subterranean wells, it is the usual practice to drive connected sections of steel tubing or easing into the hole being drilled, the casing closely following the drill which bores a hole which is slightly larger than the casing toadapt the casing sections to be readily lowered into place. During the drilling operation, drill fluid is forced down through the casing to facilitate the cutting operation, this fluid passing upwardly on the outside of the casing and carrying with it the loosened material or cuttings to the surface of the ground. As is well known to those versed in the art of well drilling, after the well has been drilled to the required depth it is necessary to perforate the wall of the casing adjacent its lower end to permit the oil or water, as the case may be, to enter the casing, the liquid then being drawn upwardly through the casing by suitable pumps.

6 Claims. (Cl. 164-0.3)

The pres- I cut invention is concerned with means for perforating the wall of the Well casing and relates particularly to a perforating device of a mechanical nature, as distinguished from the so-called gun type perforators.

Mechanically operated casing perforators now in use include a body member which is lowered into the well casing by means of a cable attached to the upper end of the body member. to the body member are upper and lower bellcrank levers, usually arranged in pairs, the levers of each. pair supporting between them a gripping member. The bell-crank levers are operated from the surface of the ground by means of a cable connected thereto, movement of the levers in one direction causing the gripping members to move radially outward into engagement with the interior of the casing so as to lock the device within the casing during a perforating operation, and movement of the levers in the opposite direction effecting inward movement of the gripping members so as to release the device. A cutter or perforating member is pivoted on each gripping member and operated by the cable which actuates the gripping members, the arrangement being such that the gripping members first lock the device within the casing and the r cutters subsequently perforate the wall of the casing.

In practice, the entire perforating device is first lowered to a point adjacent the lower end of the casing or to any other selected position and Pivoted the operating cable is then drawn upwardly to actuate the perforators or cutters so as to pierce the casing wall. It is desirable that a series of the perforations be made around the periphery of the casing and in an effort to produce such a group of perforations, the gripping members are released following each perforating operation and the entire device is turned within the casing to move the cutters to new angular positions, this indexing of the cutters being accomplished by merely turning the cables.

It has been determined that when such a means is employed and procedure is followed in spacing the perforations circumferentially of the casing, it is impossible to control the spacing with any degree of, accuracy. This is due to the fact that the long supporting cables are apt to twist so that the position of the cutter members cannot be ascertained or controlled. As a result, it often happens that theperforations are improperly spaced and, in some instances, they are disposed so close to previously formed holes that they connect with these adjacent perforations to F through which pieces of rock can pass.

It is also common practice to provide additional groups of perforations above the first or lower series of holes in the casing, the perforator being raised successively to new positions following the perforating of each series of holes. Due to the factthat the perforating device is lifted by the cable, which has considerable stretch, the exact position of the cutters is undeterminable and consequently the perforations are not made at the desired vertical locations. In other words, the perforations are quite apt to be spaced haphazardly in both horizontal and vertical directions with the result that the well casing is sometimes weakened by oversize openings which permit the entrance of stones from the earth.

It is a primary object of my invention to provide a perforating device which is especially designed to perforate well casings and which will overcome the difficulties experienced with prior 7 devices of this general character.

Another object of the invention is to provide a perforating device which, in addition to being more efficient in perforating the well casing, can be positively located in both horizontal and vertical directions by means controlled at the surface of the ground so that the perforations can be cut at selected positions and the possibility of the perforations being out too close to adjacent perforations to weaken the casing structure is thereby avoided.

Another object is to provide a device, of the character referred to, which includes a body member adapted to be lowered into the well casing, gripping members movable radially of the body member for gripping the wall of the casing to look the device in selected positions, perforating members pivoted on the body member and having cutters adapted to perforate the wall of the casing when the perforating members are pivoted radially outwardv and a slide member: slidab-le longitudinally of the body member" for actuating the perforating members. It is also an important object of my invention to provide an improved means for actuating the slide member, this means preferably consisting of a fluid cylinder mounted on the body member andia; slidabl in the cylinder and connected to. the slide member. Motive fluid introduced intbthe lower end or" the actuating cylinder movestliet slide member upwardly to operate the cutters. thetluid; under pressure passingv downwardly fromthe surfaceoi. the. groundlto this end ofthe cylinder throughza rigid. hydraulic lineextend'ingwit-hinthe veil. casing.- The above-mentioned hydraulic line is disposed within a second rig-id'- line: which has. its lower. end. connected to. the upper endv of. the. actuating cylindenthere being. a head or column. of hydraulic fluid. provided in the-second line. By this censtruction, when the pressure; is relieved within the-lower end. of. the cylinder, the column of fluid within the second line exerts'suflicient force. against the top of" the piston tolower the slide member andthus-return the cutters: to inoperative position.-

In accordance: with my invention, the upward" flow of hydraulic fiuidwithinthe. secondor outer line during, the. actuation of. the cutters may be observed. by the. operator. above the. surface of the groundand, since. this-flow is. proportional to the.- sliding movement. of. thepiston. and. pivotal movement of the. perforating members. the amount. of radial movement. imparted to the periorators. cutters. can hereadily determined. by. the. operator so. that. the. possibility of actuate ing the cutters through a. distance which. is. in-- sufdcient. to. produce. a. complete. perforating of the. casing wall. is: obviated,., thisis another important. obiectot my invention.

it. has been statedthat the. fluid; for actuatingthe: hydraulic meansis: supplied. to. the. cylinder. throughrigid tubes orlinessirom whichlthe. device is suspended. Suchastructure is-ex-tremely ins-- portant. to. the. successful. operationvv of my iniproved perforating: device since it. enables. the devicetoibeaccurately disposed atselected locationswithin. the well. casing. Since theel'ongat ing and twisting characteristics. are practically nil,v it. is apparent. that the. peri'orating device can-.berotated to selected. angular. positions or raised and lowered. to. various. vertical. positions with: a high: degree-oilv accuracy. so that.the.per iorationsi can be spaced. with great precision. constitutes an. important improvement over previous; devices of a similar nature: and... is. a. particular object ofthe-present invention.

Another. obi ect: of my invention is. to. provide a? perforating device: of? the type. indicated. having cam: means for actuating; the gripping members:

Another objectv is to provide, inadevice: of the" character; specified, anovehformofperforat-- ingselernent which functions: to.- pierce thev well casing andto bend or extrude the metal adjacent.

a side=of the pierced hole outwardly to iorm a. louver which serves to prevent stonesor. the. like '4 from entering the casing through the perforation or from wedging in the perforation to impair the how of the water or oil into the casing.

A further object is to provide a perforating device which is of relatively simple construction and one which is highly eiiicient in performing its intended function.

Further objects of my invention will appear from the following detailed description and from the drawings, which are-intended for the purpose of illustratibn only, and in which:

Fig. l is a vertical section through a drilled well, showing my improved perforating device as-lappliedto use in perforating the casing of the V743 is a side View of the device showing it located. in a well. casing, which is shown in sec tion', illustrating the gripping members in inoperative position;

Fig. 3 is a view similar to Fig. 2 but showing the members as operative to lock the device in a. selected position within the well. casing;

Fig. 4 is a longitudinal sectional view through thadevice, takenon line ='ld 01? Fig. 2. showing the. perforating. means in inoperative position;

Fig. 5 isa fragmentary sectional view of the lowenportionof the device, showing the perforating means; its operative. position;

Fig. 6 is an. enlarged fragmentary view of a portion of one of the perforating members illustrating the manner in which its cutter pier es th'ewalllot the casing; v

Fig-.fl is a-perspectiveview' of one type of perfcu'ator or cutter adapted. for use in the device;

8: is: a perspective view of a portion or" a wellicasing showing a. louver type perforationthereini-rnadeby the. cutter illustrat'e'din Fig. 6;

Fig. 9. is: a. perspective viewof a perforating element or cutter. of modified construction; and Fig. 1.0 is. aperspective view" of a portion of a welllcasingshowingithe type ofp'erforatiori or" of a well casing iii adjacent the lower end of the casing. While the well maybe a typefor obtaining various fiuidsfroni the earthgthe pres entdevice will be. described inccnnecti'on with a: wellifor obtaining water from the earth; by way. oil example. The lower end of the well casingi l5.-is.locat'ed in the water-bearing strata it whilethe upper endo'i' the casinglprojectsslightabovethe. surface ll" of the ground. As is well known. to those. versed in the art of deep well drilling, it is. necessary to perforate the casing I5. adjacentlit's lower end to permit'the water to enter. the casing, the. water then" being drawn upwardly by suitable pumping" My. improved perforating. device 26 is adapted toi-penforatethe casing. iii at any desired locationsand. is constructed'as next described. The

. device. includes, essentially, elongate body (Fig. 4:) and a. pair of. diametrically opposed slots: 24 (Fig. 3'). the openings and slots being arrangedatright angles to each other; Theb'odv member 24 haslugs-ZE at its upper end between which the lower end of" a hydraulic actuating cylinder 26 is. welded or otherwise secured. The cylinder. 26 has amend plate or cap 2'! at its uppen endQt'heoap being provided witha' threaded 7. noted that the upper cam portions 11 of the cutters act to bend or flare the metal adjacent the upper edge of the perforation outwardly and upwardly to provide louvers 8! which overlie the perforation so as to guard against the entrance of pieces of rock into the casing.

It is particularly noted, during the perforating operation, that were it not for the presence of the gripping members intermediate the body member 2| and the casing I5, the cross-section of the casing would tend to become oblong due to the lateral force component exerted by the cutters 70. By use of the gripping members, the perforation may be made without impairing the strength or altering the form of th casing, for any tendency for the casing to reduce any chordal or diametrical dimension is opposed. by the wedged body member 2! and the gripping members 50. Further, by the cooperation of the gripping members with the body member 2I, the device is maintained center-most of the well during each perforating operation. In such a manner, the locations of the perforations are known to be diametrically opposed and their location may be indexed at the ground surface. Accordingly, additional perforations may be made at the same well elevation, but angularly disposed from perforations previously made, and accurately located so as to preclude overlap of perforations that would tend to shear the casing.

The invention also contemplates the use of perforators or cutters 83 of the alternative type disclosed in Fig. 9. Such cutters may each includ a plate portion 86 adapted to be secured to the lever-arms 62, and a relatively long vertical knife 85 having a point 86 at its lower end. When the lever-arm 62 is pivoted outwardly, the point 86 pierces the wall of the casing l5 and continued movement of the cutters 83 causes their knives 85 to slice through the metal to form vertical slits 81 as shown in Fig. 10.-

Assuming that it is desirable to perforate the well casing l5 adjacent its lower end and that it is preferable to provide two vertically-spaced series of ten perforations, the perforating device 20 is lowered in the casing in the manner next ex-' plained. To lower the device 20, pipe sections 29' and 49a are added to those already attached to the actuating cylinder 26 and following the addition of each section, the device is lowered further At the same time, the

well casing l5 and the upper projecting ends of the hydraulic lines 30 and 40 are connected respectively to the reservoir and pump, not shown, and the perforating device is ready for operation.

To perform a perforating operation, that is, to provide a pair of diametrically opposite perfora tions in the wall of the casing, the operator first releases any tension that may be exerted on the cable 53, preferably by first raising the cable to its upper limit as determined by the upward travel of the annulus 41 about the pipe section 29 and then releasing the cable to permit the gripping members 50 to drop into position. As the gripping members move downwardly, their cam faces 5! and 52 act against the cam faces 55 and 55 to cause the members to move radially outward and into wedged engagement with the wall of the casing [5. Then the operator merely opens the selector valve 46 to cause hydraulic fluid to be forced down through the line 40 and into the lower end of the cylinder 26 to forcibly.

Eventually, the perforating deraise the piston 32 and thus slide the slide mem-' ber 34 upwardly. As the slide member moves upwardly, the pin 65 is also caused to be moved upwardly so that the toggle levers 6! and 6! are pivoted from the position shown in Fig. 4 to that illustrated in Fig. 5. In this manner, the perforators or cutters 10, or 83, are forced outward 1y so that they pierce the casing wall as shown in Figs. 5 and 6 to provide a pair of perforations or openings or El, as the case may be.

During the perforating operation, the hydraulic fluid within the upper end of the actuating cylinder 26 is displaced and forced upwardly into the line 30 which, as previously explained, contains a column or head of the fluid. The amount of hydraulic fluid displaced from the upper end of the line 30 or the change in level of the fiuid within this line provides an indication of the amplitude of movement of the slide member 34 so that the operator can readily determine whether the cutters have completely penetrated the wall of the casing l5. Following the perforating operation, the valve 46 is operated in a manner to permit egress of the hydraulic fluid from the lower end of the cylinder 26 and at this juncture the head of fiuid within the line 36 exerts sufficient downward force to return the slide member 34 to first position and move the perforating members to inoperative position. The

return of the gripping members 50 to first position may be facilitated by exerting an upward pull on the cable 53 to free the wedge-shaped cam faces of the members and the body member.

After the first pair of perforations has been made, the entire perforating device 20 is indexed to a new position by merely rotating the rigid lines 30 and 40. By providing index marks at the upper end of the casing l5 and on the line 30, the degree of rotation of the line 30 and perforating device 20 can be readily determined. When ten perforations are being made at one level, the device is indexed through an angle of 36 between each perforating operation to complete the series of perforations.

Following the completion of one group of ten perforations, the entire perforating device 28 is raised within the casing It to a new level by drawing the cable 53 and the lines 30 and 4| upwardly. The amount of upward movement of the device can be readily ascertained by measur ing the length of the projecting end of the line.

38 so that the perforating device Zil can be accurately located in its new position. After the device 20 has been disposed at the higher level within the casing l5, the device is operated in the sequence explained above to make a new series of perforations.

After the well casing 15 has been perforated in the foregoing manner, the device 20 is withdrawn from the casing by merely drawing the cable 53 and the line 30 upwardly by any suitable equipment and, during this operation, the uppermost tubes or pipe sections of the lines 36 and 40 are uncoupled in the manner well known to those versed in the art.

While I have herein shownand described the improved perforating device as embodied in a preferred form of construction, by way of example, it will be apparent that various changes might be made in the structure and in the manner of applying the device to use, within the spirit of the invention. Consequently I do not wish to be limited in this respect, but desire to be afforded the full scope of the appended claims.

I claim as my invention:

1. A device for perforating a well casing or the like, including: a body member adapted to be lowered into the casing and having at least two radial openings therein and provided with cam surfaces; a perforating member supported by said body member; a slide member slidable vertically in said body member and operatively connected to said perforating member to cause movement thereof to perforate said casing; fluid actuated means for sliding said slide membergya freely suspended gripping member slidable radially in each of said openings and adapted to engage the interior of the wall of the casing, each gripping member having at least one cam surface engageable by one of said cam surfaces of said body member during vertical sliding movement of said gripping member so that each gripping memher is slid radially outward into engagement with said casing wall to retain the device in selected positions in the casing; a holder slidable longitudinally of said body member and suspended from a cable lowered into the casing; and links connected between said holder and the upper ends of said gripping members for suspending said gripping members in said openings.

2. A device for perforating a well casing or the like, comprising: a body member adapted to be lowered into the casing and having at least one radial opening therein; a cam surface for said body member; a freely suspended gripping member for said opening and movable vertically relative to said body member and slidable radially outward in said opening and adapted to engage the interior of the wall of said casing, said gripping member having at least one cam surface engageable by said cam surface of said body member during vertical sliding movement of said gripping member to cause said radial movement; a holder slidable longitudinally of said body member and suspended from a cable lowered into the casing; a link connected between said holder and the upper end of said gripping member for suspending said gripping member in said opening; at least one lever-arm pivoted to said body member and provided with a perforating cutter adapted, when said lever-arm is pivoted outwardly, to pierce the wall of the casing; a slide member slidable vertically in said body member and connected with said lever-arm so that relative sliding movement between said slide member and said body member in one direction causes said lever-arm to pivot radially outward; and fluid actuated means for sliding said slide member.

3. A device for perforating a well casing or the like, comprising: a body member adapted to be lowered into the casing; a cam surface for said body member; a gripping member adapted to engage the wall of said casing and suspended adjacent to and movable vertically and laterally relative to said body member, said gripping member having a cam surface engageable by said cam surface of said body member during relative vertical movement of said gripping member to cause said lateral movement; a, holder movable longitudinally of said body member suspended in said casing; means connecting said holder and said gripping member suspending said gripping member adjacent said body member; a perforating member supported by said body member; a slide member slidable relative to said body member and operatively connected to said perforating member to cause movement thereof to perforate said casing; and means for moving said slide member.

4. A-dev'icefor perforating a well casing or the like, comprising: a body member adapted to be lowered into the casing; a plurality of cam surfaces for said body member; a plurality of grippin members adapted to engage the wall of said casing and each being suspended adjacent to and movable vertically and laterally relative to said body member, each of said gripping members having a cam surface engageable by one of said cam surfaces of said body member during relative vertical movement of said gripping member to cause said lateral movement; a holder movable longitudinally of said body member suspended in said casing; suspension means connecting said holder and said gripping members to position said gripping members relative to said body member; a lever-arm supported by said body member and provided with a perforating cutter adapted, when said lever-arm is moved toward said casing, to pierce the wall of said casing; a slide member movable relative to said body member and operatively associated with said lever-arm so that relative movement between said slide member and said body member in one direction causes said lever-arm to move toward said wall; and means for moving said slide member.

5. A device for perforating a well casing or the like, including: a body member adapted to be lowered into the casing and having an opening therein and provided with a cam surface; a first lever-arm supported by said body member; a slide member movable relative to said body member; a second lever-arm connected to said slide member and said first lever-arm so that relative movement between said slide member and said body member in one direction causes one of said lever-arms to move toward the wall of said casing; a perforating cutter for one of said leverarms adapted, when said last-mentioned leverarm is moved toward said wall, to pierce said wall; means for moving said slide member; and a suspended gripping member vertically and laterally movable in said body member opening and adapted to engage the interior of said wall, said gripping member having a cam surface engageable by said cam surface of said body member during vertical movement of said gripping member to cause said lateral movement.

6. A device for perforating a well casing or the like, comprising: a body member adapted to be lowered into the casing and having at least one opening therein; a cam portion for said body member; a suspended gripping member for each said opening and movable vertically relative to said body member and slidable outward in said opening and adapted to engage the interior wall of said casing; a cam surface for each of said gripping members for engagement with the cam portion or" said body member during vertical movement of said gripping members to cause their outward movement to retain the device in selected positions in the casing; suspension means for said gripping member slidable longitudinally of said body member and suspended within said casing; means connecting said suspension means and said gripping members for suspending each gripping member in its body member opening; a first lever-arm pivotally connected to said body member; a slide member movable relative to said body member; a second lever-arm pivotally con nected to said slide member and said first leverarm so that relative movement of said slide member and said body member causes one of said lever-arms to move toward the wall of the said casing; a perforating cutter lor said lever-arm LOUIS D. BARBER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Williamson Aug. 15, 1882 Kafader Nov. 10, 1891 Plecker Apr. 24, 1894 Mills June 3, 1913 Number 12 Name Date Schneider Aug. 26, 1919 Stewart et a1 Dec. 16, 1924 Cameron et a1 June 30, 1925 Trumble June 17, 1930 Moss Dec. 16, 1930 Lee Dec. 22, 1931 Dillon May 21, 1935 Hanes July 5, 1938 Lane Jan. 30, 1940 Brack Sept. 24, 1940 Scivally July 14, 1942 Page Feb. 10, 1948

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Classifications
U.S. Classification166/55.2, 166/217, 294/95, 166/213, 166/212, 72/325
International ClassificationE21B43/11, E21B43/112
Cooperative ClassificationE21B43/112
European ClassificationE21B43/112