US2748874A

US2748874A - Godevil for cable suspended well tools

Info

Publication number: US2748874A
Application number: US255612A
Authority: US
Inventors: Spencer Lloyd
Original assignee: JOHN D CHESNUT; THOMAS C BANNON
Current assignee: JOHN D CHESNUT; THOMAS C BANNON
Priority date: 1951-11-09
Filing date: 1951-11-09
Publication date: 1956-06-05
Anticipated expiration: 1973-06-05

Description

June 5, 1956 SPENCER GODEVIL FOR CABLE SUSPENDED WELL. TOOLS 2 Sheets-Sheet l Filed Nov. 9, 1951 iIz////////////////////// ?1 IN V EN TOR m ma 4 June 5, 1956 L. SPENCER GODEVIL FOR CABLE SUSPENDED WELL TOOLS 2 Sheets-Sheet 2 Filed Nov. 9 l951 I VENTOR.

United States Patent *O e 2,74s,s74 GoDEvL FOR CAELE SUSPENDED WELL TOOLS" Lloyd Spencer, -Los Angeles, Calif., assignor of thirtythree and one-thirri per cent to Thomas C. Bannon, Altadena, Calif., and thirty-three and one-thirri per cent to John D. Chesnut, Newport Beach, Calif. e

Application November 9, 1951, Serial No; %5,612 13 Claims. (Cl. 166-243):

My invention relates to godevils for cable Suspended oil well tools, for example, but not-limited to, gun perfo- 'rators. 4

Included in the objects of my invention are:

First, to provide a godevil which is so arranged that it may drop or slide through an oil well casing containing a cable from which a tool is-suspended`without tanglng or interfering with the cable.

Second, to provide a godevil which is not strung onto the suspensioncab1e but is disposed alongside the cable and is so arrarged that irrespective of the position the cable occupies in the circle represented by the casing, the godevil is capable of moving to clear the cable without binding thereon.

Third, to provide a godevil which is not influenced in its travel down the casing by the tension existing in the cable or the bearing load of the cable against the side wall of the casing such as may exist ata "dog leg or bend in the e casi'ng.- p

Fourth, to provide a godevil which involves a body structure with substantally tangentially disposed spring loaded vanes, or yieldable rubber vanes, or radially expansible and contractable vanes, arranged to bear against the surrounding' casing so that the body structure is yieldably maintained in a central position, the body structure being capable of being urged to any side of center by a cable present in the well casing so that the cable may occupy such center position, and wherein the godevil is in its entirety rotatable in the casing around the axis of the cable.

With the above and other objects in View, reference is directed to the accompanying drawings, in which:

figure 1 is an exaggerated, foreshortened and'sub stantially diagrammatical View of a well casing showing a cable Suspended well tool and mygodevil.

` Figure 2 isa top view of my godevil as it appears when fitted in a casing, indicatng by broken lines a displaced position of the godevil and indicating by dotted circles several typical positions of a cable.

Figure 3 is a fragmentary longitudinal sectional View with portions in elevation taken along the line 3-3 of Fig. 2.

Figure 4 is a fragmentary transverse sectional view thereof taken through 4-4 of Fig. 3.

Figure 5 is a bottom end View of the striker foot forming the lower extremity of my godevil.

Figure 6 is a fragmentary transverse 'sectional View of a modified form of my godevil.

'figure 7 is a fragmentary longitudinal sectional View thereof taken alo-ng the line 7-7 of Fig. 6.

Figure' 8 is a fragmentary side view of a further modified form of my godevil.

Figure 9 is an enlarged transverse sectional view through 9-9 of Fig. 8. I

Figure 10 is a fragmentary transverse sectional view through 10-10 of Fig. 8. v

. Figure 11 is a fr'agmentary longitudinal sectional view ,through 11-11 of Fig. 8. v i

2,748,874 Patented June 5, 1956 Reference is first directed to Figures 1 through 5. The godevil here shown includes a central pin 1 on which is threaded a series of core members 2 separated by collars 3. The core members are provided with radating arms 4, in the Construction illustrated, three such arms being shown. The lower end of the pin 1 screwthreads into a striker foot 5 also having radating arms 6. The upper end of the central pin extends through a head member 7. At its lower portion the head member is provided with radiating-lugs 8 corresponding to the arms 4. Above the lugs 8 the head member 7 is provided with wickers 9, for use in the event it becomes necessary to retrieve the godevil by means of a fishing tool. V p

T he lugs 8, arms 4 and 6 have alined vertical openings which receive hinge pins 10 screwthreaded into the striker foot 5. Journaled on each hinge pin between the series of core members 2 are vane element-s 11. The vane elements are notched as indicated by 12 to clear the arms of the core members and bring their axial extremites into confronting relation. The vane elements are joined axially by pins 13 to form three vane structures.

Certain of the notches 12 are axially enlarged to clear the adjacent core member and provide space for torsion springs 14, the extremities of which are anchored in the core members and vane elements in such a manner that the vane structures tend to rotate in one direction on their hinge pins 10; that is clockwise, as viewed in Figs. 2 and 4. Thus, when the godevil is placed in a well casing the vane -structures bear against the walls of the casing and yieldably retain the body of the godevil represented by the core members 2 in the center of the casing.

The upper and lower end vane elements are beveled as indicated by 15 to facilitate travel either upwardly or downwardly in the well casing. Also the radially inner and outer ends of the vane elements are rounded. The length of the go-devil is preferably several times the 'diameter of the casirg, and is determined by--the weight desired. While it is preferred to construct the godevil of steel, it may be made of drillable material such as cast iron or aluminum.

Reference is now directed to Figs. 6 and 7. The godevil here shown comprises a central core or body 21 having radiating webs 22 around which is molded or cemented avcovering of rubber or other elastomer. .The covering 2.3 joins integrally to semi-flexible radating arms or vanes 24, which, when the godevil is inserted in a casing, bend circumferentially to bear against the walls of the casing in the manner of the vane structures of the first described embodiment. The lower extremity of the core 21 may be exposed to form a striker foot 25. p

The core, except its striker foot may be formed of lead or heavy alloy, and the rubber comprising the covering and vanes may be provided with suitable weighting material to givethe godevil thetdesired mass. It is'desirable to so compound the rubber or rubber-like material that it may be drilled up in the event the godevil should not be retrieved. The upper end of the modified godevil is preferably provided with means not shown for engagement by a fishing'tool in the manner of the first described structure. p

Deep wells, such as oil wells, are not truly straight but twist and turn. This is true not only of slant drilled wells but also of vertical wells. The radius of curvature is, however, quite large for the reason that the radius about which the drill pipe can be bent and rotated during the drilling of the well is quite large.

Before utilizing either form of my godevil, a Well tool, such as a gun=perforator C, is lowered by a cable B to the desired level. By reason of the elongated curves and twists in the well, the cable in its course from the mouth of the well to the well tool gradually shifts its position relative t'o the walls of the c'a'sing. :The: position 'of the cable within the circle defined by the .casing 'thus varies infinitely, as partially indicated by the series of dotted circles in Fig 2.

. After the well tool is in position, the godevil is inserted. If the cable occupies the center of the `casing the central bodyof the godevil may be otfset as indicated by broken lines in Fig. 2. Under such condition, the vane structures iof either embodiment shown maintain their yieldable en- -gagement with the walls of the casing As the cable moves from a centered position toward the walls of the casing, the spring action of the vane structures shift the body circumferentially around the cable so that the body is between the cable and the far side of the well casing. -If the cable bears against the walls of the casing, as it will on the inside of a curved portion of 'the casing, the extremities of the vane structure may ride along the cable and possibly jump over the cable without harm. It will be observed that the change in position of the cable takes place quite `gradually. By reason of the angular arrangement of the vane structures there is a slight tendency of the godevil to rotate slowly in a clockwise direction, but

the rotational forces are quite nominal so that the hearing 'by the loading of the springs 14 orthe elastic character of the vanes 23, rather than the bearing load of the cable against the walls of the casing. To amplify, the cable bears against the walls of the casing in relation to the tension of the cable, created by the weight of the cable and well tool, the radius of curvature of the casing, and the length of cable between its points of tangency to the curve. Cumulatively this can be so severe that there can be no assurance that a conventional godevil threaded on the cable will drop the full distance or will not hang up at some point in the casing. It has been largely for this reason that cable Suspended godevil operated tools have not been successfully used. Thus, the conditions governing movement of my godevil may be predetermined, and its travel assured until stopped by the well tool it is intended to engage.

Sufficient radial range of movement of the vanes may be provided to permit a single size godevil to operate in several sizes of casing, or to pass from a larger into a smaller diameter casing. Also, the size of the cable is imnaterial. The cable may be 'a "send" line of large diameter, or a single strand line of quite small diameter, known as a measuring line.

Reference is directed to Figures 8 through 11. The structure here shown is, like the first described structures, so arrangcd that the body or central portion may be entirely displaced from the center of the casing when urged therefrom by the cable.

Three sheet metal strips 31 are folded longitudinally to form V members with their leaves at 120 angle. The strips 31 are fastened at their extremities by riveting or welding to spacer bars 32 having arms radiating in 120 relationship. Between the spacer bars 32, the strips define radiating slide channels 33 which receive slide bars 34. The extremities of the slide bars 34 confront the spacer bars 32 and springs such as leaf sprngs 35 are disposed between the spacer bars and slide bars to urge the slide bars radially against the surrounding casing.

The slide bars may be restrained against axial or longitudinal movement by internal ribs 36 .formed radially in the slots or channels 33 which fit grooves 37 formed in the sides of the bars 34. Radial movement is limited by rivets 38 extending between the strips 31 through clearance openings 39 provided in the slide bars. It will be observed that the central portion of the godevil is open and that flow may occur around the springs 35. Also the openings 39 are large. The purpose of this is to avoid packing or accumulation of ysand or other Suspended matter in the openings of the godevil which might interfete with its operation.

The spacer bars 32 project axially beyond and are radially enlarged to guard the ends of the slide bars 34. The spacer bars then reduce radially to form heads 40 which may have wicker notches 41. Either head may be inserted first and 'form the impact head of the godevil.

The modified form of my godevil provides sufficiem radial contraction of the vanes or slide bars 35 that the central portion tor body defined by the intersection of the radiating arms may be displaced from the center by the cable, as shown in Fig. 9 wherein the cable B is represented in outline and boundaries of a concentric casing A' indicated by broken line.

lt will be observed that if movement of the cable is resisted by two arms or vanes, that the pressure point of the cable is offset or more on one vane than the other and thus tending to rotate the godevil free of the cable. Due to the fact that the godevil is in motion, resistauoe to rotation is 'only nominal :even through the hearing pressure of the vanes against the casing may be substantial. If the pressure point of the cable is in line with a vane,

this is an Unstable condition and the godevil tends to rotate in either direction away from this condition.

Having thus described certain embodiments of my invention, I do not desire to be limited thereto, but claim all novelty inherent in the appended claims.

:I claim:

l. A godevil adapted to travel freely within a well casing through which extends a cable, comprising: an elongated body structure adapted to be received in a casing alongside of a cable suspcnded therein; and yieldable arms connected to said body structure and adapted to bear against the side of said -casing structure and tending to maintain said body structure in the center thereof,

said godevil body structure being displaceable by said cable to a position entirely to one side of the center of .the casing while remaining slidable in the casing along side of said cable.

2. A godevil as set forth in claim 1 wherein: said arms are formed at .least inpart from an elastomer and bend into yielding contact with the surrounding casing.

3. A godevil as set forth in claim 1 wherein: said arms include rigid portions directed radially from said body structure and movable portions capable of radial expansion and contraction.

4. VA godevil as set forth in claim l wherein: said arms are radially .expansible and contractiblc.

5. A godeviliasset forth in claim 1 wherein: said arms are hinged to said body structure and springs urge said arms into contact with the surrounding casing.

6. A godevil adapted to travel freely within a well casing through which extends a cable, comprising: an elongated body structure adapted to be received within a casing alongsde a cable Suspended therein; yieldable arms having radially inner portions ?connected to said elongated body structure and radially outer portions adapted to be circumferentially displaced with respect to said body structure and bear slidably against a surrounding casing, said godevil body structure thereby being displaceable by said cable to 'a position entirely to one side of the center of the casing alongside said cable while said arms remain in slidable contact with the walls of said casing.

7. A godevil as set `forth ,in claim 6 wherein: the radially inner portonsof said arms are hinged to said body structure and springs urge said arms into contact with the surrounding casing.

8. A godevil as set;forth in claim 6 wherein: said arms are formed at least in part from an elastomer and bend into yielding contact with the surrounding casing.

9. A godevil adapted to travel freely within a well casing through which extends a cable, comprising: an elongated body structure adapted :to be received within a casng alongsde a cable Suspended therein; a pluralty of elongated yieldable vane structures radiating from said body structure adapted to slide longitudinally and progress circumferentially within a surrounding casng while engaging the walls thereof and tending to maintain said body structure centered in said casing, the sides of said vane structures and body structure adapted for sliding contact with said cable, said godevil body structure being displaceable by said cable to a position entirely to one side of the center of the casing while said vane structures remain in engagement with said casing.

10. A godevil as set forth in claim 9 wherein: hinge means having axes longitudinally of said body structure connect said vane structures -to said body structure, and said vane structures are displaced crcumferentially when fitted within said casing.

11. A godevil as set forth in claim 9 wherein: said vane structures are formed at least in part of an elastomer and bend yieldably between said body structure and said casing.

12. A godevl as set forth in claim 9 wherein: said vane structures are radially expansible and contractible.

13. A godevil as set forth in claim 9 wherein: each of said valve structures includes a radially inner portion rigidly connected to said body structure, a radially outer portion, and a radially expansible and contractible connection between said portions.

References Cited in the file of this patent UNITED STATES PATENTS` 2,195,871 Kuster Apr. 2, 1940 2,248,160 Crawford July 8, 1941 2,402,223 Wright June 18, 1946 2,438,673 McMahan Mar. 30, 1948