US2586878A

US2586878A - Drilling apparatus

Info

Publication number: US2586878A
Application number: US746712A
Authority: US
Inventors: James C Staton
Original assignee: Eastman Oil Well Survey Co
Current assignee: Eastman Oil Well Survey Co
Priority date: 1947-05-08
Filing date: 1947-05-08
Publication date: 1952-02-26
Anticipated expiration: 1969-02-26

Description

Feb. 26, 1952 J. c. STATON DRILLING APPARATUS Fi led May 8, 194'? 2 SI-IEETS-SHEET 1 gwuwwbom Feb. 26, 1952 J. c. STAT ON DRILLING APPARATUS 2 SHEETS-SHEET 2 Filed May 8, 1947 im AI l James. C. Stator? Patented Feb. 26 1952 2,586,878 panama APPARATUS James C. Staton, Corpus Christi, Tex., assignmto Eastman Oil Well Survey Company, Denver, 0010., a corporation of Delaware Application May 8, 1947, Serial No. 746,712

Claims.

This invention relates to new and useful improvements in drilling apparatus.

One object of the invention is to provide an improved apparatus wherein a whipstock is detachably connected to a drill pipe or stem so that it may be lowered and raised within the well bore by means of said pipe; the apparatus including an improved drilling assembly having means for drilling a full-gauge, oflfset bore when drilling oil of the whipstock face occurs, whereby subsequent reaming or hole-enlarging operations are not necessary to complete said offset bore. An important object of the invention is to provide an apparatus which combines a removable-type whipstock with an improved drilling assembly, with said assembly having normally retracted reaming means which is automatically expanded into reaming or cutting position after the offset drilling operation is begun, whereby reaming or enlargement of the well bore is accomplished at the same time that the offset bore is drilled.

Another object of the invention is to provide an improved drilling apparatus or assembly having a drill bit at its lower end and having expansible reaming means spaced above said bit, with said reaming means being resiliently maintained in a retracted position and being movable outwardly into cutting position by the imposition of a predetermined weight upon the assembly, whereby expansion of the reaming means is effected when desired and after the drilling operation is begun; said reaming means being constructed so as to immediately and automatically return to its retracted position as soon as the predetermined weight on the apparatus or assembly is released.

A further object of the invention is to provide an improved drilling apparatus, of the character described, wherein reamer cutting blades are pivotally mounted on the body of the apparatus and wherein an expanding element which is arranged to co-act with said blades is telescopically mounted with relation to the blades, whereby when said element is moved with respect to the blades, the latter are expanded into cutting position; said expanding element being moved when the weight of the drill pipe or stem is imposed upon the apparatus during the drilling operation to automatically expand the blades when the drilling operation is begun.

Still another object of the invention is to provide a combined whipstock and drilling apparatus wherein said apparatus is connected to whip- 2 stock by means of a left-hand thread connection, whereby detachment of the apparatus from the whipstock may be effected by rotating the apparatus in a direction opposite to the direction of rotation which is required for normal drilling.

The construction designed to carry out the invention will be hereinafter described together with other features of the invention.

The invention will be more readily understood from a reading of the following speciflcationand by reference to the accompanying drawing, wherein an example of the invention is shown, and wherein:

Figure 1, is a view partly in section and partly in elevation of the improved drilling apparatus, constructed in accordance with the invention and combined with a removable-type whipstock,

Figure 2 is a similar view showing the drilling apparatus detached from the whipstock and also showing the position of said apparatus after it has drilled off of the whipstock face,

Figure 3 is an enlarged, transverse, vertical, sectional view of the drilling apparatus with the reaming cutters in a normally retracted position,

Figure 4 is a similar view showing the reaming cutters moved to an expanded or cutting position,

Figure 5 is an enlarged, horizontal; cross-sectional view taken on the line 5-'-5 of Figure 3, and

Figure 6 is an enlarged, horizontal, cross-sectional view taken on the line 66 of Figure 4.

In the drawings, the numeral l0 designates a Whipstock or deflecting tool which is constructed of a wedge-shaped body portion H having an inclined guide surface l2. The upper end of the body II has an integral section [3 and the upper end of the section has a recovery collar I4 integral therewith. The section I3 is substantially a straight wall section and as will be explained, the drilling apparatus A is disposed opposite this section when said apparatus is connected to the whipstock. It is noted that the whip-stock is of the removable type, that is, it is arranged to be lowered and raised within the well bore B by means of the drill pipe I5 which has connection with the drilling apparatus or assembly A. This type of whipstock is illustrated in the prior patent to McVicar No. 1,970,761.

The drilling apparatus A which is combined with the whipstock 10 comprises a main housing or cylinder 16 which has itslower end connected 19 which forms a cylinder and an internal annular shoulder or enlargement 26 is formed within the housing at the lower end of this cylinder. Below the internal shoulder 20, the housing is provided with diametrically opposed, radially extending slots 2| within which reamer blades 22 are movable. As illustrated in Figures and 6.

tain the reamer blades in a retracted or inwardv position with respect to the housing, a coil spring 24 has its ends secured to the lower portions of the blades, said spring functioning to hold said lower ends inwardly of the casing. It will be apparent that when the blades move outwardly through the slots 2| to the position shown in Figure 4, said blades assume a cutting position and upon rotation of the housing will effect a reaming operation of the bore which has been drilled by the drill bit 18.

For moving the reamer blades 22 to an outward or expanded position, a longitudinally movable expanding element is movable between the diametrically opposed blades. lustrated in Figures 3 and 4, the element 25 is in the form of a tubular shank which has its upper end preferably made integral with a piston member 26, the latter being movable within the cylinder l9. The lower end of the expanding member is flared outwardly as indicated at 21 and.

longitudinal grooves 28 which are adapted to receive the rear edges ofthe reamer blades, are formed in the side wall of said element. Because of these grooves the blades and the main housing IE will be rotated with the drill stem. When the piston 26 and its expanding element 25 are in the position shown in Figure 3, said expanding element is in a raised position with respect to the reamer blades 22 and in such position, the coil spring 24 holds said blades in a retracted or inner position. When the piston 26 is moved downwardly within its cylinder, the expanding element moves downwardly with respect to the reamer blades 22, whereby the flared lower end 21 of the expanding element co-acts with the rear edges of the blades which swing said blades outwardly into an expanding or cutting position. Of course, this outward swinging movement of the blades is against the tension of the coil spring 24 which connects the blades. So long as the expanding element is in the lowered position (Figure 6), the blades 22 are extended outwardly and a rotation of the apparatus will result in carrying out the reaming operation.

In order to retract the blades 22, it is only necessary that the piston 26 and its expanding element 25 be moved upwardly with respect to said blades and as said element returns to the position shown in Figure 3, the connecting coil spring 24 will immediately retract the blades. When in a retracted position, the outer longitudinal cutting edges of the blades are substantially within the confines of the outer diameter of the housing l6 so that said blades will not hang up as the assembly is lowered or raised within the well bore.

For controlling the movement of the piston 26 and its associated expanding element 25, said piston is formed with an upwardly projecting As is clearly il- 3' tubular extension 29 which is made integral therewith. The extension 29 projects through an opening 30 in the upper end of the housing 16 and has its upper portion enlarged at 3l,- whereby an external annular shoulder 32 is provided on the exterior thereof. The extreme upper end of the extension 29 is coupled, to the drill pipe l5, whereby th'en'tire assembly is suspended from said pipe. The extension 29 is formed with an axial bore 33 and a reduced bore 34 which extends entirely through said extension, piston 26 and expanding elements 25 so that circulation downwardly through the device to the reamer blades 22 and drill bit 18 may be accomplished.

In order to maintain the piston 26 in its raised position so that an inclined beveled shoulder 35 on said piston may engage an internal beveled seat 36 within the housing, a spring 31 surrounds the reduced lower portion of the extension and is confined between the upper end of the housing I6 and the external shoulder 32 on said extension. This spring is relatively strong and is of a predetermined tension and obviously exerts its pressure to urge the extension upwardly with respect to the housing; thus, the piston 26 is normally maintained in a raised position within its cylinder with the shoulder 35 at its upper end engaging the seat 36 within said housing. It is obvious that in order to move the piston 26 downwardly, a weight suflicient to collapse the spring 31 must be imposed on the extension 29. Collapse of the spring is accomplished by imposing the weight of the drill pipe or stem l5 upon the member, after the drill bit l8 has engaged the formation and is holding the housing l6 stationary.

For connecting the drill apparatus or assembly A to the whipstock I0, the enlarged upper portion 3| of the extension 29 is formed with a series of coarse left-hand threads 38 which are disposed externally thereof. Co-acting coarse internal threads 39 are provided within the recovery collar M of the whipstock l0 and make it possible to detachably connected the extension 29 of the drilling apparatus or assembly A to said collar.

- The connected position of the parts is illustrated in Figure 1 and in such position, the drilling apparatus or assembly A is disposed opposite the straight wall section l3 of the whipstock; at this t me the reamer blades 22 are in a retracted position.

In order to make it possible to orient the whipstock so that its guide face I2 is disposed in a proper azimuthal position or direction, the tubular extension is provided with a magnet 40 which is mounted in its wall. When the

threads

38 and 39 are coupled together to connect the drilling apparatus or assembly A to the whipstock I0, the magnet 40 is disposed in the vertical plane in which the whipstock guide face is directed. Thus, by using any of the well known methods of determining the position of the magnet 40, it is possible to determine in which direction the whipstock face is pointing so that proper orientation of the whipstock may be carried out and subsequent drilling in a desired direction accomplished. An example of the methods which may be employed for locating the position of the magnet and, therefore, the azimuthal position of the whipstock face [2 are illustrated in the patents to R. S. Hyer No. 2,120,670 and L. C. Miller No. 2,327,658.

In the operation, the drilling apparatus or as sembly A is coupled to the recovery ring l4 of the whipstock M by connecting the coarse left-hand threads 38 of the extension 29 to the internal aaaaare threads 39 within the collar. In this position, the drilling apparatus abuts or extends contiguously to the straight wall section l3 of the whipstock III, as shown in Figure 1 and at this time the relatively strong spring 31 is maintaining the extension 29 raised with respect to the housing It.

It is evident that the extension telescopes the housing and so long as the spring 31 urges the extension upwardly with respect to the housing, the piston 26 is in its raised position within the cylinder I9 of said housing. At this time, the expanding element 25 connected to said piston is raised with respect to the reamer blades 22 (Figure 3) and said blades are held in their inneror retracted position by the coil spring 24-.

Obviously since the drilling apparatus or assembly which is attached to the drill pipe [5, is coupled to the whipstock, the drill pipe may be utilized to lower the complete assembly into position within the well bore B. The whipstock is lowered until it strikes a cement plug C provided for the purpose or engages the formation at the lower end of the bore. Upon reaching the lower end of the bore, the position of the whipstock face l2, that is the direction in which this surface is facing, may be determined by lowering a magnetic instrument (not shown) through the drill pipe into a position opposite the magnet 40. By means of a photographic record obtained by said instrument, the position of the magnet may be determined, whereby the azimuthal position of the guide face of the whipstock may be ascertained. After the azimuthal position of the whipstock face is known it is obvious that a rotation may be imparted thereto to dispose said face in a desired direction so ,that subsequent drilling may be performed in a desired direction. Of course, it may not be necessary or required that the direction or position of the whipstock face be known, in which case the determination of the position of the magnet 40 need not be accomplished. After setting of the whipstock, the drill pipe is rotated in a direction to uncouple the left-

hand threads

38 and 39. It is noted that the frictional engagement of the whipstock with either the cement plug or the formation is sufficient to hold the recovery collar stationary so that a rotation of the drill pipe will accomplish uncoupling of the

threads

38 and 39.

After the drilling apparatus or assembly A is uncoupled from the whipstock, said apparatus is lowered downwardly and the drill bit I8 is guided by the inclined face l2 of said whipstock into engagement with the formation. The operator will know the whipstock is uncoupled be cause the drill stem can move freely downwardly. When the drill bit l8 engages the formation, the drill pipe is rotated and suflicient weight is imposed upon the drill bit to perform the drilling operation. The operator will know when sufficient weight is imposed because if too much weight is imposed the stem will have a quick dropping movement due to compression of spring 31. This weight issufiicient to force the bit 18 into the formation but the spring 31 is strong enough to prevent any telescoping movement of the extension 29 with respect to the reamer blade housing [6 so that at this time, the reamer blades remain in a retracted position. Drilling by the bit 18 continues in this manner until the pilot hole or til weight is sufficient to collapse the spring 31 which normally prevents telescoping of the extension 29 with respect to the housing 15. Collapse of the spring 31 allows the extension to move downwardly with respect to the housing, whereby the piston 26 and its expanding element 25 are moved downwardly with relation to the pivoted reamer blades 22. It will be obvious that as the expanding element 25 moves between the blades 22, said blades are swung outwardly to their expanded or reaming position, as illustrated in Figure 4. It is noted that downward movement of the piston 26 and its expanding element 25 are limited by the lower end of the piston 26 striking the internal shoulder 20 within the cylinder l9. So long as the weight suflicient to maintain the spring 31 collapsed is imposed on the assembly, the reamer blades 22 remain in an expanded position and the continued rotation of the drill pipe results in the blades carrying out a reaming or hole enlarging operation as a follow up to the pilot bore D being drilled by the bit l8.

The blades 22 are arranged to move outwardly a distance which will be sufiicient to form a full gauge bore and, therefore, the deflected or angular bore which is drilled by the assembly will be of the same size as the original well bore B. Drilling of the deflected or angular bore may be continued until said deflected bore has suflicient depth to subsequently guide an ordinary bit thereinto.

To remove the assembly, it is only necessary to lift the drill pipe and the drilling apparatus upwardly until the threads 38 of the apparatus engage the internal threads 39 of the recovery collar, after which these threads may be recoupled. Subsequent upward lifting of the drill pipe to remove the apparatus A will simultaneously remove the whipstock l0 therewith.

From the foregoing it will be seen that a relatively simple apparatus which permits the drilling of a deflected or angular bore to full gauge is provided. The coupling arrangement through the use of the left-hand coarse threads eliminates the use of shear pins and this obviates the possibility of unintentionally disconnecting the drilling apparatus from the whipstock. The reaming blades 22 are normally maintained in a retracted position and may be held in this position as long as desired. In other words, the expansion of the reamer blades is controlled solely by the operator through the imposition of the weight on the drill pipe. There may be instances where it is not desirable to actuate the reamer blades and in such case, drilling of the deflected or angular bore will be accomplished by the drill bit l8 and this may be done by imposing only sufficient weight to cause digging by the bit l8 without collapsing the spring 31.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

l. A rotary earth bore drilling apparatus including, a deflecting tool, a drilling assembly detachably connected to said deflecting tool, said assembly comprising a rotatable drill pipe, an earth drill bit rotatably connected to the lower end of said pipe, an expansible reaming means mounted in the drill pipe above the bit and normally in a retracted position, the apparatus be- 7 ing lowered into a well bore as a unit to locate the deflecting tool within the bore, means for disconnecting the drilling assembly from the tool to permit a rotary earth drilling operation to be carried out with the drill bit rotating relatively to and being guided in its direction by the deflecting tool, and means actuated by relative longitudinal movement of the drill pipe with respect to the reaming means for expanding thereaming means whereby reaming of the bore drilled by the drill bit may be accomplished without removing the apparatus from said bore.

2. A rotary earth bore drilling apparatus including, a deflecting tool, a drilling assembly detachably connected with the deflecting tool tracted position, means operable from the surface for disconnecting the drilling assembly from the tool when the latter is properly located within the bore, whereby subsequent lowering and rotation of the drill pipe results in the drill bit performing a drilling operation with said bit rotating relatively to and being guided by the deflecting tool, and means actuated by relative longitudinal movement of the drill pipe with respect to the reaming means for expanding the reaming means, whereby movement of the reaming means into and out of reaming position is controlled from the surface.

3. A drilling apparatus as set forth in claim 1, wherein the deflecting tool is a whipstock having a recovery collar at its upper end and also wherein the detachable connection between the drilling assembly and the whipstock comprises coarse left-hand threads on said assembly and within the collar of said whipstock.

4. A drilling apparatus as set forth in claim 2, wherein the deflecting tool is a whipstock having a recovery collar at its upper end and also wherein the detachable connection between the drilling assembly and the whipstock comprises coarse left-hand threads on said assembly and within the collar of said whipstock.

5. A drilling apparatus as set forth in claim 2, wherein the expansible reaming means comprises pivoted cutting blades which are mounted to swing inwardly and outwardly in a radial direction with respect to the drill pipe.

6. A rotary earth bore drilling apparatus including, a deflecting tool, a drilling assembly detachabiy connected with the deflecting tool whereby said assembly and tool may be lowered into the bore as a unit to position said tool at the desired depth in the bore, said drilling assembly comprising, a rotatable drill pipe, a reamer housing having expansible cutting blades which are normally in a retracted position, means for connecting the reamer housing to the drill pipe to permit said pipe and housing to be moved axially with respect to each other, means actuated by the movement of the pipe axially with respect to the housing for expanding the cutter blades, a drill bit secured to the lower end of the drill pipe below the reamer housing, and means actuated from the surface by manipulation of the drill pipe for detaching the drilling assembly from the deflecting tool, whereby a drilling operation may be carried out.

7. A rotary earth bore drilling apparatus including, a deflecting tool, a drilling assembly dev normally in a retracted position, means for con- 4 necting the reamer housing to the drill pipe to permit said pipe and housing to be moved axially with respect to each other, means actuated by the movement of the pipe axially with respect to the housing for expanding the cutter blades, a drill bit rotatably connected to the lowerend of the drill pipe below the reamer housing, and means actuated from the surface by manipulation of the drill pipe for detaching the drilling assembly from the deflecting tool, whereby a drilling operation may be carried out, axial movement of the drill pipe with respect to the reamer housing being effected by theimposition of a predetermined weight upon said drilling assembly through the drill pipe, whereby expansion and retraction of the reamer blades may be controlled from the surface.

8. A rotary earth bore drilling apparatus including, a deflecting tool, a drilling assembly detachably connected with the deflecting tool whereby said assembly and tool may be lowered into the bore as a unit to position said tool at the desired depth in the bore, said drilling assembly comprising, a rotatable drill pipe, a reamer hous ing having expansible reaming cutters which are normally in a retracted position, a telescoping connection between the housing and the drill pipe whereby these parts may move a limited distance with respect to each other, means actuated by the movement of the drill pipe with relation to the housing for expanding the reaming cutters, resilient means associated with the telescoping connection for normally holding the pipe and housing in a position with the reamer cutters retracted, a drill bit connected to the lower end of the reamer housing, and means operable by manipulation of the drill pipe from the surface of the well bore for disconnecting the drilling assembly from the deflecting tool, whereby the assembly may be subsequently lowered and rotated to perform a drilling operation which is guided by the deflecting tool.

9. A rotary earth bore drilling apparatus for drilling a bore at an angle to and of approximately the same diameter as a, bore extending from the surface, said apparatus comprising a defleeting tool, a rotatable drill pipe, means for connecting the deflecting tool to the drill stem for lowering into the bore from the surface and for then permitting disconnection of the tool by a relative movement between the pipe and tool to thereby permit the pipe to rotate relatively to the tool, a drill bit rotatably connected to the lower end of the drill pipe below its connection with the deflecting tool and capable of being deflected by the tool and by pipe rotation drilling a bore at an angle to and of less diameter than the bore from the surface, expansible reaming means carried by the drill pipe above the drill bit and normally positioned to be inoperative, and means operable by a relative longitudinal movement of the drill pipe with respect to the reaming means for expanding the reaming means so that it will function to enlarge the bore drilled by the bit as the drill pipe is rotated.

10. A rotary earth bore drilling apparatus for drilling a bore at an angle to and of approximately the same diameter as a bore extending from the surface, said apparatus comprising a deflecting tool, a rotatable drill pipe, means for connecting the deflecting tool to the drill stem for .iowering into the bore from the surface and for then permitting disconnection of the tool by a relative movement between the pipe and tool to thereby permit the pipe to rotate relatively to the tool, a member mounted on the lower end of the drill pipe below its connection with the deflecting tool for rotation with the pipe but capable of axial movement with respect thereto, a drill bit mounted on said member and capable of being deflected by the tool and by pipe rotation drilling a bore at an angle to and of less diameter than the bore from the surface, expansible reaming means carried by the member above the drill bit and normally positioned to be inoperative, and means 10- operable by the moving of the pipe relatively to the member for expanding the reaming means so as to enlarge the bore drilled by the bit as the pipe is rotated.

JAMES C. STATON.

REFERENCES CITED --The following references are of record in the file of this patent:

UNITED' STATES PATENTS Number Name Date 1,795,553 Getty Mar. 10, 1931 1,955,631 Harris Apr. 17, 1934 1,970,761 McVicar Aug. 21, 1934 2,108,419 Trotter Feb. 15, 1938 2,120,670 Hyer June 14, 1938 2,327,658 Miller Aug. 24, 1943