US2595401A

US2595401A - Drill head

Info

Publication number: US2595401A
Application number: US633934A
Authority: US
Inventors: Moon James
Original assignee: Signal Oil and Gas Co
Current assignee: Signal Oil and Gas Co
Priority date: 1945-12-10
Filing date: 1945-12-10
Publication date: 1952-05-06
Anticipated expiration: 1969-05-06

Description

May 6, 1952 Filed DGO. lO, 1945 J. MOON DRILL HEAD 2 SHEETS-SHEET l HYDRAULIC JACK HYDRAULIC JACK INA/EN Tok,

(IH/115,5 Moo AT TOR/Vex May 6, 1952 J. MOON 2,595,401

DRILL HEAD Filed Dec. 1o, 1945 2 SHEETS-SHEET 2 INVENTQR.

IIA/w55 Moo/v A T TO/ZNE y'.

Patented May 6, 1952 DRILL HEAD James Moon, Altadena, Calif.,.assignor to Signal Oil and Gas Company, Los Angeles, Calif., a

corporation of Delaware Application December 10, 1945, Serial No. 633,934

Claims. (01;'255-23) n" invention relates toa combined drill head and motor assembly.

In conventional rotary assemblies for rotary `drilling of bore holes for oil or gas wells, the drill pipe is rotated by and passed vertically through the rotary drill table. The drill pipe and casing is handled by the conventional drilling rig. A conventional swivel is employed for passage of mud fluid into the drill pipe.

It is an object of my invention to design a power operated drill head and swivel structure which may be mounted upon a power operated hoist and which will move together with the drill pipe as the drill pipe advances during drilling and will also function to rotate the drill pipe.

My drill head is particularly adapted for use with hydraulically operated jacks which are so mounted as to advance the drill pipe or casing into or-withdraw drill pipe or casing from the bore hole.v

It is a further object of my invention to design such a drill head wherein the motive power for rotation of the drill pipe may be mounted with the drill head and advance therewith, and to reduce the size of the power unit by employing a plurality of such power units.

'It is an additional object of my invention to provide means for transmitting the power to the drill head through a plurality of shafts, each separately connected to a source of motive power mounted in association with said drill head.

It is a further object of my invention to so mount the drill stem in association with the drill head that the loads imposed longitudinally of the drill stem are not transmitted to the gear system by which the rotary power is transmitted from the shafts to the drill stem.

These and other objects of my invention will be better understood by reference to the accompanying drawings which illustrate a preferred embcdiment of my invention, and in which:

Fig. 1 shows an assembly view showing the mounting of my drill head on a well bore drilling machine;

Fig. 2 is an end View of Fig. 1; and

Fig. 3 is a sectional view of my drill head taken along the line 3-3 of Fig. 2.

In Fig. 1 the drilling machine I includes braces 2 which also act as the longitudinal braces of the machine and the longitudinal braces 3. Transverse end braces 4 and

transverse braces

5 and 6, and angular braces l are also provided at .suitable places to impart rigidity to the structure. y Mounted on transverse brace 6 is a pair of hydraulic jacks 8 and 9. The cylindersv are mounted on 5 and pass through the transvers'brace 5. The jack piston rods il' and Iii are connected to the yoke II which is mounted on rollers l2 adapted to roll on braces 2 which act as tracks.

Mounted on cross brace 5 and connected to brace 3 is a pair of hydraulic jacks I3 and It. The jack piston rods are connected to yoke I5 which moves on rollers I8 guided on the braces 3' which act as tracks therefor.

Slips Il are mounted on brace 5 and slips Ii! on brace 6. Mounted on yoke I5 are the compound slips IS and 2). Bolted to yoke II is the combination drill head and swivel assembly 2l.

The drill head box 22 (see Fig. 3) carries the cylindrical journal boxes 23 in which are positioned the sleeves 2d carrying bearings 26 and 28. The .bevel gear 23' is mounted on hollow shaft 2l in bearing 26. Shaft 2l is keyed in the tube 25 and mounted in bearing 2S and packed off at 28a. The shaft 3l is driven by a gear formed of a ring gear 2S! mounted on a disc 3@ which rotates on ball bearings 3io. The hollow shaft 3I is driven by 30 through the splines 3 Ia in bearings 3Ib and is packed olf at 33. The housing is bolted to I I so that the drive shaft 3l is in axial alignment with the slips l'I and the drill pipe 4i. The shaft 3i carries a load disc 32 abutting against 3B. There is no rotational connection between 32 and 43E) except through shaft 3l via splines 3Ia. The shaft 3l operates against a thrust bearing 34 mounted in the housing cover` 35. Telescoping into shaft 3| and suitably packed by packing 36 is a stationary tube 3l carried on the spider 38 formed integrally with the cover 35. A ilange connection 39 holds the tube 3i in the spider and in the packing.

Mounted on the yoke I I' (see Fig. l) is a pair of power units 46 connected to the shafts 2'I. These vpower units may be a pair of electric motors, such as synchronous motors connected to a common supply of alternating current, or a pair of hydraulic motors connected in parallel to a common supply of fluid such as oil under pressure. Such hydraulic motors are Well known and one example thereof is the type described in Patents No. 2,320,727 and No. 2,313,407. These motors have the characteristic such that for a given setting of the motor the speed is dependent on the volume of the applied uid and so long as this volume is maintained constant for any motor setting, the speed of the motor remains constant. A

Fig. 1 shows two such Vickers hydraulic motors mounted on the yoke I I and connected, one each, to the shafts 2l.

The use of such means of motive power with a plurality of gears 28 to drive the single gear 29, preferably spaced around said drive gear 29 and in mesh therewith, and each driven by a separate power shaft 21, has a number of advantages. It permits of the application of a large amount of power to the gear 29 while employing relatively small gears such as 28', and thus the size of the gear box may be kept small. This is highly desirable for a drill head which is to be mounted on the yoke II. By placing a number of gears 28' and the associated power unit at various positions around the periphery of the gear 21, the size of each power unit can be minimized. Two such gears and power units are vshown in Fig. 3. A larger number may be used. By using a multiplicity of small gears instead of a single gear, I am able to balance wear load on the gears 28' and the gears 29 so as to get uniform tooth wear. By using a multiplicity of gears we are able to apply a total drive load to gear 28 equal to the sum of the loads applied via each pinion gear. The total tooth pressure is held to the pressure applied by the pinions and will thus be materially less than the tooth pressure required to transmit the same load through one pinion gear.

Since, however, each gear 28' is operated from a separate power unit, I have found it desirable that the speed of all of the gears 29' be the same. Where all the gears 28 are the same size, this means that the shafts 21 should rotate at the same R. P. M.

Where these shafts are operated from different power units there is a danger that these speeds cannot be kept at the desired equal R. EP. M. I have provided a simple means for obtaining this synchronized speed. Thus, by employing hydraulic motors such as described above and assuring, by proper manifolding, that the fluid pressure applied to each motor is the same and that the volume of fluid at such pressure is the same to each motor, I can be sure that the motors will rotate all shafts 21 at the same speed. This is accomplished by a balanced manifolding of the fluid inlets and outlets from the hydraulic motors and by adjusting the setting of the hydraulic motors. As an alternative I may employ, when space considerations permit, A. C. synchronous motors in parallel driven from the same source of A. C., so that each motor will turn at the same speed determined by the current characteristics in the feed line. In these manners, also, I may rotate all shafts 21 at the same speed.

The connection between shaft 3| and 39 forms a floating mounting of drive shaft 3|. As shown in Fig. 3, any upward thrust of the spindle 3|, occasioned as will be described below, will be transmitted to the thrust bearing 34 and will not be transmitted to the ring gear 29. This is caused by the spline connection 3Iaand the absence of any connection between 3l' and 3G whereby any thrust toward bearing 34 is transferred to the disc 30. This is important since it assures that the alignment of the

gears

23 and 29 will be unaltered notwithstanding the sudden and large variations in load which occur during drilling, as will be described below. Any upward thrust on the gear 29 will cause a jamming of the teeth of 29 into the teeth of 28 and thus cause an acceleration of wear and an excessive loading of gear 28.

Any reverse load on spindle 3l causes a pressure of the load disc 32 against the disc Sil which is transmitted to the bearings 3Ic. Additionally, any thrust load occurring during rotation of 29 by 28 is also taken up by 3Ic. In this manner 4 the relationship of the

gears

29 and 28 remains unaltered notwithstanding any sudden and large variation of load on the spindle 3 I In operation, the yoke II, being at its extreme position with piston rods 9 and I0 in full retard position and its extreme position near 5the slips i1 are set to grip pipe 4I and the connection at e2 is broken. The rods 9 and I9 are extended to separate II from 5 and a section of pipe is lntroduced and connected to the drill pipe in slips Il' and to connection 42. Slips I1 are opened and again the pipe is advanced through the open slips Il by attaching the piston rods 9 and I0. Zin this manner pipe is advanced until the drill d in drilling position in the bore hole. Slips il' are opened and 39 is connected to a hose for mud iluid. The power is connected to '40 and drilling is commenced. The gears 2S' rotate 29 and this rotates the spindle SI via the splines 3 Ia. The tube 31 is stationary While 3| rotates. As drilling is continued the mud is circulated down and through the swivel connection 31 through Si and down the drill pipe, and returns up the bore hole outside the drill pipe.

In advancing the drill pipe by retracting the jacii piston rods 9 and IIJ, during rotation of the pipe by means of 3| or with the rotation interrupted, the resistance to the advance of the drill pipe down the hole causes a thrust up the drill pipe and spindle 3i which is taken up by the thrust bearing 34 with the results described above.

When it is desired to withdraw the drill pipe from the bore, for example, when the drill is to be changed, the reverse procedure is followed. With the slips I1 open the piston rods 9' and I0 are extended. The slips I1 are set to grip pipe di and the joint 'I2 is broken and the pipe uncoupled above the slips I1. The loosened joint is removed. The rods 9 and I9 are retracted and the pipe in the slips I'I is joined to the spindle 3| by the joint 42. The slips I1 are freed and another joint of pipe 4I is withdrawn by extending the rods S and IIB. In this manner the pipe may be withdrawn from the bore.

In thus operating, the resistance of the pipe, due to its weight and drag, causes a pull on the spindle 3| which is taken up in the bearings 3I with the results described above.

Provision is made in the drilling machine for introducing casing. With the drill pipe entirely withdrawn from the well, casing is run through the slips I9, 29, and I8, and with slips I9 set and 2i) and I8 open, the casing is introduced into the well by jacks I3 and Ill. In similar manner the casing may be withdrawn by opening slips I9 and I8 and setting slip 29.

While I have described a particular embodiment of my invention for the purpose of illustra- "5 tion, it should be understood that various modifications and adaptations thereof may be made within the spirit of the invention as set forth in the appended claims.

I claim:

l. A bore hole drilling head, comprising a hollow drill pipe drive shaft, means for connecting said drive shaft to drill pipe, a drive gear, a spline connection between said shaft and said drive gear, said shaft being driven by said gear through said spline connection, pinion gear in meshing engagement with said drive gear, a power shaft for said pinion gear, means for transferring the axial load on said drive shaft to said gear in one axial direction only, said means including a load disc on said drive shaft abutting the side of said drive gear between said gear and said thrust bearing, the shaft being mounted for relatively free movement in said gear in the opposite axial direction, and a thrust bearing for said gear mounted against the opposite side of said drive gear.

2. A bore hole drilling head, comprising a hollow drill pipe drive shaft, means for rigidly connecting said drive shaft to said drill pipe, a drive gear, a spline Aconnection between said shaft and said drive gear, said shaft being driven by said gear through said spline connection, a plurality of pinion gears peripherally spaced around said drive gear and each in meshing relation with said drive gear, a drive shaft for each pinion gear, a thrust bearing for said drill pipe drive shaft, means for transferring the axial load on said drive shaft to said gear in one axial direction only, said means including a load disc on said shaft abutting the side of said drive gear between said gear and said thrust bearing, the shaft being mounted for relatively free movement in said gear in the opposite axial direction, and a thrust bearing for said gear mounted against the opposite side of said drive gear.

3. A drill head adapted for rotating and advancing and lowering of drill pipe into and from bore holes for wells drilled in the earth, which coinprisesa housing, a hollow drive shaft in said housing, means for rigidly connecting said drive shaft to said drill pipe, a drill pipe advancing and withdrawing means, means for mounting said housing on said advancing and withdrawing means with said hollow drive shaft in axial alignment with the drill pipe, a drive gear in said housing, a spline connection between said drive shaft and said drive gear, a pinion gear in said housing in mesh with said drive gear, means for transferring the axial load on said drive shaft to said gear in one axial direction only, said means including a thrust bearing for said shaft mounted on said housing, a load disc on said hollow shaft abutting said drive gear and mounted on said shaft between said drive gears and said thrust bearing, the shaft being mounted for relatively free movement in said gear in the opposite axial direction, and a thrust bearing in said housing mounted on the opposite side of said gear.

4. A drill head adapted for rotating and advancing and lowering of drill pipe into and from bore holes for wells drilled in the earth, which comprises a housing, a hollow drive shaft in said housing, means for rigidly connecting said drive shaft to said drill pipe, a drill pipe advancing and withdrawing means, means for mounting said housing on said advancing and withdrawing means with said hollow drive shaft in axial alignment with the drill pipe, a drive gear in said housing, a spline connection between said drive shaft and said drive gear, a plurality of pinion gears peripherally spaced about said drive gear in meshing relation therewith, a thrust bearing for said shaft mounted on said housing, means for transferring the axial load on said drive shaft to said gear in one axial direction only, said means including a load disc on said hollow shaft abutting said drive gear and mounted on said shaft between said drive gear and said thrust bearing, the shaft being mounted for relatively free Inovement in said gear in the opposite axial direction, and a thrust bearing in lsaid housing mounted on the opposite side of said gear.

5. In a power transmission device, a drive shaft, means for connecting said drive shaft to drill pipe, a drive gear, a spline connection between said shaft and said drive gear, said shaft being driven by said gear through said spline connection, pinion gear in meshing engagement with said drive gear, a power shaft for said pinion gear, a thrust bearing for said drive shaft, means for transferring the axial load on said drive shaft only in one axial direction to said gear, said means including a load disc on said drive shaft abutting the side of said drive gear between said gear and said thrust bearing, the shaft being mounted for relatively free movement in said gear in the opposite axial direction, and a thrust bearing for said gear mounted against the opposite side of said drive gear.

JAMES MOON.

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

UNITED STATES PATENTS