US2770444A

US2770444A - Circulating and rotating retrievable whipstock

Info

Publication number: US2770444A
Application number: US341423A
Authority: US
Inventors: Stephen A Neal
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-03-10
Filing date: 1953-03-10
Publication date: 1956-11-13
Anticipated expiration: 1973-11-13

Description

WWW. 13, S. A. NEAL. CIRCULATING AND ROTATING RETRIEVABLE WHIPSTOCK Filed March 10, 1953 2 Sheets-Sheet l IN V .EN TOR.

4 TTOP/VE'KS Nmr, 13, 1956 s. A. NEAL 2,770,444

CIRCULATING AND ROTATING RETRIEVABLE WHIPSTOCK Filed March 10', 1953 2 Sheets-Sheet 2 IN VEN TOR.

JTEPH'A/ WEAL Unitd States Patent CIRCULATWG AND ROTATING RETRIEVABLE WHESTOCK Stephen A. Neal, Odessa, Tex.

Application March 10, 1953, Serial No. 341,423

2 (Ilaims. (Cl. JESS-1.6)

This invention relates to a whipstock such as that used with a drill collar during the drilling of an oil well.

As presently used, a Whipstock is inserted in the hole being drilled, and is retained in a stationary position upon the bottom of the hole. The conventional whipstock includes an inclined surface, along which the drill bit moves, said inclined surface being effective to change the direction of the hole.

The main object of the present invention is to provide a generally improved whipstock of the rotatable, retrievable, fluid circulating type. A further object of importance is to provide a whipstock as stated wherein fluid will circulate through the whipstock when the whipstock and drill collar are connected for joint rotation.

Another object is to provide a whipstock construction wherein the circulation of fluid through the whipstock will be prevented as soon as the drill collar is free from the whipstock, for rotation independently of the now stationary whipstock.

Another object is to provide a whipstock and drill collar assembly in which the means normally providing communication between the whipstock fluid conduit and the drill collar fluid passage will also be the means normally connecting the drill collar and whipstock for joint rotation, shearing of said means under predetermined, controlled conditions being effective to operate a valve so as to close the drill collar passage at that location at which said passage is normally in communication with the whipstock fluid conduit.

Yet another object is to provide, in a whipstock and drill collar assembly as stated, a second valve mounted in the drill collar and disposed in a normally closed position, said second valve being adapted to prevent passage of the drilling fluid out of the lower end of the drill collar into the hole until such time as the drill collar is freed for rotation independently of the whipstock.

Other objects will appear from the following descrip tion, the claims appended thereto, and from the annexed drawings, in which like reference characters designate like parts throughout the several views, and wherein:

Figure 1 is a longitudinal sectional View through a whipstock and drill collar formed in accordance with the present invention, portions being broken away, the parts being shown in the position assumed thereby when the drill collar and whipstock are being rotated as a single unit;

Figure 2 is an elevational view in which portions are broken away, taken from the right of Figure 1;

Figure 3 is an enlarged transverse sectional view on line 3-3 of Figure 1, showing the valve means whereby the movement of fluid from the drill collar passage to the whipstock conduit is controlled;

Figure 4 is an enlarged transverse sectional view on line 44 of Figure 1;

Figure 5 is an enlarged transverse sectional view on line 5-5 of Figure 1;

Figure 6 is an enlarged fragmentary longitudinal sectional view through the drill collar and the valve assembly 2,770,444 Patented Nov. 13, 1956 Fee whereby movement of fluid out of the lower end of the drill collar is controlled;

Figure 7 is a transverse sectional view on line 7-7 of Figure 6;

Figure 8 is a transverse sectional view through a modified form of drill collar and whipstock; and

Figure 9 is a fragmentary perspective view of the modified form shown in Figure 8.

The invention includes a drill collar 10 and a whipstock designated generally by the reference numeral 12. The drill collar, as is usual, has an axial passage 14 for a fluid substance used in drilling operations, such as drilling mud. The passage 14 opens upon the lower end of the drill collar 10, said open lower end of the drill collar being formed with a tapered, threaded counterbore 16 in which is engaged a conventionally formed drill bit 18.

A short distance above the tapered counterbore 16, I form a circumferential shoulder 20 in the drill collar passage 14, and fixedly mounted in said passage, and seating against the shoulder 20, is a valve assembly designated generally by the reference numeral 22. The valve assembly 22 includes a cylindrical body 24 fitting tightly against the wall of passage 14, and formed open at its opposite ends. Intermediate its ends, the: cylindrical body 24 is formed with circumferentially spaced, large openings 26. Bit 18 holds assembly 22 in place.

Referring to Figure 6, in which the valve assembly 22 is particularly well shown, in one end of the body 24, said end being the lower end of the body, I fixedly mount a spider 28 having a center opening in which is slidably mounted a valve stem 30. The valve stem is extended axially of the body 24 and drill collar 10, and is mounted in the body to shift in the direction of its own length.

Fixedly secured to the valve stem 30, intermediate opposite ends of the valve stem, is a collar 32, said collar extending through the full circumference of said stem and being adapted, in one position of the valve stem, to bear against the spider 28.

On the upper end of the stem 30, there is fixedly mounted a disc-shaped valve 34 having a peripheral groove in which is seated a sealing ring 36 adapted to prevent leakage between the outer circumference of the valve 34 and the inner wall of the cylindrical body 24.

Shear pins 37 (Figure 7) extend between the valve 34 and the wall of the valve body 24, so as to normally hold the valve 34 in the full line position thereof shown in Figure 6. In this position of valve 34, it prevents the movement of drilling mud out of the passage 14, since the valve 34 extends transversely across said passage and completely closes said passage when valve 34 is in its full line position.

If, however, the valve 34 shifts to the dotted line position thereof shown in Figure 6, the drilling mud can move around the valve, circulating through the openings 26 of the cylindrical body 24.

The shear pins 37 are selected so as to be of a strength that will normally resist movement of the valve 34 to its open position under the ordinary pressure of drilling mud. The pins 37 will, however, shear when the pressure of the mud against the valve 34 is increased to a predetermined extent.

Movement of the valve 34 beyond the dotted line position shown in Figure 6 is prevented by engagement of collar 32 against spider 28.

In the wall of passage 14, at a location above the valve assembly 22, I form a recess 38 in which is fixedly mounted one end of a valve guide sleeve 44 (Figure 3). A valve rod 42 is slidably mounted in the sleeve 40, and fixedly connected to the outer end of rod 42 is a valve member 44. A coil spring 46 abuts at one end against the valve member 44, and at its other end against the wall of passage 14, said spring 46 being held under compression so as to normally urge the rod 42 and valve member 44 outwardly from the guide sleeve 40, toward the right in Figure 3.

The whipstock' comprises, anaelongatedbody formed, at its upper end, with'a sleeve portion. 8 circumposed about. the drill collar 11).: Anfieccentrically disposed opening it) (Figure 3) is formed in the sleeve portioni48, the drill collar extending; through said opening;

in the sleeve portion-43, there ismounted a rectangularv block 552, said bioclr being. welded or otherwise ailixed to the sleeve portion, in arec'ess shaped to snugly receive the block; Block 52 has-a threaded opening formed therein, and threadedly engaged insaid opening is atubuiar member or conduit 54, the outer end of whiclris closed as at 56. in the. closed end 56of the tubular 'member there is formed. a centrally located, threaded opening, andengaged in said opening is a complementarity threaded bolt 53;

As will be noted from Figure 3, the drill collar 10 has a threaded opening registering with the threaded opening of-the block 52,.the threaded opening ofthe drill collar having the inner end of the tubular member 54 engaged therein. Thus, under normal conditions the drill collar and whipstock are connected forjoint rotation, by the tubular member. The tubular member, however, is selected so as to be of a strength that will resist shearing of said member until the whipstocl; has been rotated to a desiredextent in the bottom of the hole, and has been set. Thereafter, downward'pressure n the drill collar will be effective to shear the tubular member 54, thereby to allow the drill collar to rotate independently of the now stationary \vhipstock.

The bolt 555 projects inwardly within the passage 14, engaging at its inner end the valve member 44. As a result, the valve member 44 is restrained, by bolt 58, against movement to a closed position in which it seats against and closes the normally open inner end of tubular member It will be appreciated that when the tubular member 54shears, the bolt 58 will also shear and as a result, spring 46, tending to expand, will instantaneously shift the valve member to a seated position, thus to cause the movement of drilling mud from passage 14 into the tubular-member to be halted simultaneously with the freeing of the drill collar lit for independent rotation.

The body of the whiostock includes not only the sleeve portion but also a body portion 60 integral with and depending from said sleeve portion. The body portion tit! is formed, for the greatest part of its length, with a transversely curved outer surface 62.

At its upper end, the body portion 60 is of constant thickness, for a distance extending from the sleeve portion 48 to the lower end of drill collar 1%. Throughout this part of its length, the body portion 60 has a transversely curved inner surface 64- which, considered in the direction' of its length, is in parallelism with the axis of rotation of the drill collar ltl.

Beginning at the lower end of the drill bit 18, however, the inner surface of the whipstock is inclined, so as to progressively increase the whipstock in thickness toward the lower end thereof. The inclined surface of the whipstock has been designated by the reference numeral 66, and it will be understood that after the drill collar 10 is freed from the whipstock for rotation independently of the whipstock, downward movement of the drill collar relative to the now stationary whipstock will cause the drill bit 18 to move along the inclined surface 66, thereby to change the direction in which the hole is being drilled.

As will be seen from Figure 1, the bottom edge of the sleeve portion 48 of the whipstock defines a shoulder 68, the inner diameter of which is slightly smaller than the outer. diameter of the drill bit 18. As a result, when the drilling apparatus is to be liftedfrom the hole, the

4 drill bit 13 will engage the shoulder 63, and thus the whipstock can be retrieved.

At its lower end the inclined inner surface 66 of the whipstock body portion 6t) merges into an oppositely inclined, relatively short end surface 7%. The end surface 70 extends into convergence with the inclined surface 72, which merges into the previously described outer surface 62 of the whipstoclc body portion. The surface 72 is substantially longer than the surface 7d, said surfaces 70, '72 cooperating to define a pointed end on the lower end of the whipstock which pointed end will be extended perpendicularly to the length of tubular member 54 when the drill collar is secured to the whipstock by member 54.

Extending the full length of the outer surface 62 is a longitudinal groove '74, said groove extending from the block 52 and merging into a groove extension 76 formed in the beveled end surface 72. The groove extension 76 opens, at its lower end, upon the other end surface 70.

Mounted in the groove 74- and groove extension 76 is an elongatedpipe 75;. Pipe '73, at its upper end, is in continuous communication with the outer end portion of tubular member At its lower end, the pipe 78 opens upon the tip or pointed lower end of the Whipstock body. The pipe 73 is retained within the grooveand groove extension by spot welds 79 spaced longitudinally thereof.

At selected intervals along the length of the whipstock body portion, lateral openings all can be formed, said opening communicating between the outer and inner surfaces of the whipstocl: so as to aid in the circulation of the drilling mud within the hole.

it will be seen that when the drill collar and whipstock are first lowered into the hole, they will be connected for joint rotation by the tubular member 54. At this time,

valve member 4-4 will be unseated, while the valve 34 will' be in its closed position. Therefore, if drilling mud or some other fluid substance used in drilling operations is directed downwardly through the passage 14, it will be prevented against movement through the drill bit 18, out of the lower end of said passage. Rather, said mud will be forced into the tubular member 5 4, and will pass from the tubular member 54 into the pipe 78. The drilling mud will then be forced out of the open lower end of-th'e pipe, thereby aiding in the proper preparation of the bottom of the hole found desirable preliminary to setting of the Whipstock in its stationary or anchored position.

After the whipst-ock has been rotated as necessary, and has had the desired amount of drilling mud circulated therethrough, it will be set in the bottom of the hole, and downward pressure on the drill collar 10 will be effective to shear the tubular member 54 and the bolt 58 in sequence. The downward movement of the drill collar 10 after shearing the member 54 is sufliciently rapid and forceful to shear the bolt 58 without bending. With the shearing of the bolt 58, the portion of the bolt adjacent the closed end 56 of the member'54 is first sheared followed by the shearing of the portion extending from the sheared end of the bolt 58' to the valve 44, the latter portion, when sheared, being retained in the portion of the tubular member 54 defined by the block 52.

As soon as the tubular member 54, and its associated bolt 53 are sheared, valve member 44 will move to a position in which it closes the inner end of the tubular member. As a result, the drilling mud will no longer circulate through the pipe 78.

A predetermined increase in the pressure of the drilling mud against the valve 34 will now be effective to shear the pins 37, and this will cause the valve 34 to move to its open position shown in dotted lines in Figure 6. The drilling mud will, accordingly, now be free to move out of the lower end of the drill collar, through the drill bit-18, during normal drilling operations.

Under some circumstances, the increase in pressure against the valve member 34 will be the direct result of the closing of the tubular member 54, thus to cause the tubular member to be closed simultaneously with the opening of the lower end of the drill collar 1d and freeing of the drill collar for rotation independently of the whipstock.

In Figures 8 and 9, there is shown a modified form in which the two valve assemblies will be identical to those illustrated in connection with the first form. In this second form of the invention, the drill collar has been designated by the reference numeral 82, said drill collar having, in spaced relation to its lower end, a hexagonal or other non-circular outer surface The hexagonal outer surface 84 complements the correspondingly formed inner surface 86 of a whips'tock designated generally by the reference 83.

It will be seen that when the drill collar is in the position thereof shown in Figure 1, it will rotate conjointly with the whipstock, during the preparation of the whipstock for anchoring thereof in the bottom of the hole. When, however, the whipstoclc has been fully set, the drill collar will be lowered relative to the whipstock, thereby shifting the hexagonal outer surface 84 to a location below the sleeve portion of the whipstock. There will now be disposed, in the sleeve portion of the whipstock, a part of the drill collar which is of circular cross sectional configuration so far as its outer surface is concerned, and the drill collar will thus be free to rotate relative to the whipstock.

All other pants of the assembly are unchanged.

It is believed apparent that the invention is not necessarily confined to the specific use or uses thereof described above, since it may be utilized for any purpose to which it may be suited. Nor is the invention to be necessarily limited to the specific construction illustrated and described, since such construction is only intended to be illustrative of .the principles of operation and the means presently devised to carry out said principles, it being considered that the invention comprehends any minor change in construction that may be permitted within the scope of the appended claims.

What is claimed is:

1. In a drilling apparatus including a drill collar formed with a passage for a fluid drilling substance, a whipstock arranged longitudinally exteriorly of said drill collar and having a pipe extending longitudinally therealong, a shearable conduit extending between and connecting said whipstock and said drill collar for rotation together as a unit, said conduit connecting said drill collar passage to said Whipstock pipe and being shearable upon longitudinal movement of the drill collar relative to the Whipstock, valve means positioned within said drill collar passage and normally spaced from said conduit and operatively connected to said drill collar, a frangible element positioned within and extending laterally through said conduit so as to be sheared therewith and engaging said valve means to hold said valve means in the normally spaced position with said conduit, and means operatively connected to said valve means for moving said valve means into closing position with the portion of the conduit remaining in the drill collar after shearing of said element and said conduit.

2. In a drilling apparatus including a drill collar formed with a passage for a fluid drilling substance, a whipstock arranged longitudinally exteriorly of said drill collar and having a pipe extending longitudinally therealo-ng, a shearable conduit extending between and connecting said whipstock and said drill collar for rotation together as a unit, said conduit connecting said drill collar passage to said Whipstocl; pipe and being shearable upon longitudinal movement of the drill collar relative to the whipstoclt, valve means positioned within said drill collar passage and normally spaced from said conduit and operatively connected to said drill collar, 2. frangible element positioned within and extending laterally through said conduit so as to be sheared therewith and engaging said valve means to hold said valve means in the normally spaced position from said conduit, and spring means operatively connected to said valve means for urging said valve means into closing position with the portion of the conduit remaining in the drill collar after shear-ing of said element and said conduit.

References Cited in the file of this patent UNITED STATES PATENTS 2,108,419 Trotter Feb. 15, 1938 2,196,517 Bolton Apr. 9, 1940 2,357,330 Hyer Sept. 5, 1944