US3381766A

US3381766A - Drilling system

Info

Publication number: US3381766A
Application number: US409735A
Authority: US
Inventors: Clyde E Bannister
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-11-09
Filing date: 1964-11-09
Publication date: 1968-05-07
Anticipated expiration: 1985-05-07

Description

May 7, 1968 c. E. BANNISTER DRILLING SYSTEM 3 Sheets-Sheet l Filed Nov. 9, 1964 CONT/ML V R m f M um m om r T A a M f. ,my w n May 7, 1968 c. E. 'BANNsTER 3,381,766

DRILLING SYSTEM Filed Nov. 9, 1964 5 Sheets-Sheet fi CYyQ/e f. `50/7/7/5 fer INVENTOR BY www T 555mm- ATTO/PNE? May 7, w58 c. E. BANNISTER l 3,381,766

DRILLING SYSTEM 5 Sheets-Sheet 3 Filed Nov. 9, 1964 C75/de en/WJ /e/f INVENTOR BY @MT hamm 3,381,766 DRILLING SYSTEM Clyde E. Bannister, 2727 Carolina Way, Houston, Tex. 77005 Filed Nov. 9, 1964, Ser. No. 469,735 Claims. (Cl. 17E-i166) The present invention relates to the field of subsurface exploration and drilling systems utilized therefor, and more particularly to a system especially useful for drilling large holes in the earth.

One of the prior art drilling systems for oil exploration and recovery and the like was the apparatus commonly termed a rotary rig. The rotary rig included a derrick at the surface for suspending a drill string and a motor and mechanism for rotating the drill string to turn a bit attached at its far end. The cuttings were removed by a fluid sent down the drill string and tiowing back to the surface through the borehole annulus, the space between the drill string and the borehole Wall.

In many applications the fluid force or pressure was not sufficient to remove the cuttings as fast as necessary. The dcrease in pressure was most evident When the hole size was increased, whereby the uid iiowed from a drill string having a relatively small opening into the vast expanse of the borehole annulus.

One approach employed with some success for large holes was the reverse circulation technique. As described in the article 72-in. Holes are Being Drilled, by Robert G. Burke, in the May 4, 1964 issue of The Oil and Gas Journal, pages 71-73, the drillers utilized reverse-air circulation in which air was pushed down the annulus of the borehole, across the bit face, and returned through the drill string. A very high capacity compressor had to be used to develop even a relatively low pressure and there still was circulation loss and inadequate tluid force at times.

Recognizing the limitations of the prior art, I have invented a drilling system which is capable of maintaing a high uid pressure to remove the cuttings rapidly and which does not require an extremely large fluid pump or compressor. My invention can be used to drill large holes, such as the shafts required by the Atomic Energy Commission for underground nuclear explosions.

My invention is not limited to use with a rotary rig. In fact, I disclose herein an embodiment of drilling apparatus that has the advantages of high iiuid pressure and minimum non-drilling time. This embodiment utilizes a bit driven by an oscillating motor to grind up the cuttings into pieces that can be removed easily. The oscillating motor is iiuid actuated and I have provided a valve arrangement which is especially advantageous where a high fluid pressure is controlled.

The above objects and advantages are obtainable with my invention, wherein the borehole annulus is not used as a conduit for the liuid and, instead, means is provided in the drill string, for example, to carry the liuid into and out of the borehole. A seal is established adjacent the bit to prevent the uid from exiting through the borehole annulus. The cuttings are washed with a high pressure fluid carried down the drill string and the uid and cuttings are carried up the drill string by the fluid at high pressure to the surface.

In one embodiment of my invention, a drilling system with an oscillating bit can be provided with a seal adjacent the driving motor and flexible hose can carry the fluid down to and out of the depths of the borehole. The oscillating bit grinds up the earth into very small pieces and the cuttings require only a small exhaust hose.

In connection with my invention, I have provided control means for the seal means, so that the drilling apparatus can be disposed freely in the borehole, and at a States Patent O ICC desired depth the seal means can be actuated from the surface to close olf the borehole annulus. In one embodiment the iiuid in the drilling apparatus actuates the seal means. The seal means in one form can be an expandable means, such as a rin-g or tube around the drilling apparatus which is inflated by a pressure generator. The pressure generator can be disposed in the drilling apparatus, actuated by the uid pressure to produce an even greater pressure for inating the tube. The control means can selectively actuate the seal means to establish or release the seal. The drilling can continue with the seal established and moving forward with the drilling apparatus.

My improved valve for a iiuid motor or other devices receiving a high pressure is arranged to minimize the antiunseating fluid force. A relief hole is provided in the valve closure member and a closure means is provided for the relief hole. The closure means is removed prior to unseating the valve closure member to relief the fluid pressure. In accordance with my invention, a valve also can be jarred prior to unseating to eliminate sticking. In an embodiment with a valve rod, the valve closure member can be freely mounted thereon and the valve rod can have an engaging means spaced from the valve closure member to move a given distance with the valve rod before striking the valve closure member.

These and other objects of my invention are illustrated by several preferred embodiments to be described with reference to the drawings, wherein FIG. l is an elevation view, partially in section, showing one embodiment of a drilling system in accordance with my invention.

FIG. 2 shows in more detail one form of pneumatic control means for operating the seal means of the drilling system shown in FIG. 1 or of other drilling systems.

FIG. 3 is a horizontal section along the lines 3--3 of FIG. 1.

FIG. 4 is an enlarged view of one form of sealing means for the drilling system of FIG. l or other drilling systems.

FIG. 5 is an elevation view in section of a tiuid motor equipped with my improved valve.

FIG. 6 is an enlarged elevation view, partially sectioned, of the valve shown in FIG. 5.

FIG. 7 is an elevation view, partially sectioned, of another from of drilling apparatus in accordance with my invention.

FIG. 8 is an elevation View, partially in section, of a rotary rig arranged in accordance with my invention.

FIG. 9 is a horizontal section along the lines 9*-9 of FIG. 8, showing the internal arrangement of a drill pipe.

FIG. l0 is a horizontal section along the lines 10-10 of FIG. 8, showing the internal arrangement of a drill collar.

A description of several preferred embodiments of my invention follows next. It will be obvious to one skilled in the art, after reading my description, that other apparatus is equally capable of using my invention and that changes and modifications in the disclosed apparatus embodiments can be made Without departing from my invention.

A drilling system in accordance with my invention is capable of drilling lange holes, such as a hole or borehole 1 (FIG. 1). Borehole 1 may be as large as six feet in diameter. One possible way of drilling borehole 1 would be to use conventional drilling equipment, such as a rotary rig or oscillating drill system. With a rotary rig, a bit would be supported in borehole 1 by the drill string and rotated in one direction therewith. The cuttings would be removed by uid ilowing down the drill string and out the borehole annulus. But if the fluid must expand into at large volume of the borehole annulus, the uid pressure drops and the cuttings are not washed away rapidly enough. Reversing the fluid flow route, into the borehole through the borehole annulus and out the drill string, requires a very large capacity pump and the fluid pres sure or velocity is not always suicient to remove large cuttings.

I have shown in FIG. l a drilling apparatus 2 capable of operating in large borehole 1 with a high fluid velocity. In general, fluid is carried into borehole 1 by conduit means in drilling apparatus 2 and a bit 3, disposed at the end of the drill apparatus 2, is rotated to remove portions or cuttings from the borehole bottom 4. The uid washes the cuttings out of the borehole through another conduit means in the drilling apparatus 2 at a high pressure. The exhaust conduit means takes the place of the borehole annulus and has the advantage of a constant, relatively small but adequate size, irrespective of the -borehole size, to maintain a high fluid pressure.

To prevent the iluid from exiting through the borehole annulus 6, I provide a seal means adjacent bit 3 which substantially closes off borehole annulus 6. Seal means 5 is operated Iselectively by a control means to open or close off annulus 6 at will. Drilling can continue while borehole annulus 6 is closed to penetrate further into the earth '7.

The particular form of drilling apparatus shown in FIG. 1 utilizes an oscillating, fluid actuated motor S mounted in a cylindrical housing 9. Motor 8 can be of several types, such as the improved motor disclosed in my copending application, Ser. No. 265,839 filed Mar. 18, 1963, now U.S. Patent 3,183,787. Fluid enters housing 9 through a flexible inlet hose 10 and is coupled to motor 8 to sustain oscillating movement of an impeller blade coupled to drive shaft 11. The oscillating movement is coupled to bit 3 through clutch 12 and an intermediate shaft 13 threaded at one end to engage bit 3 and mounted for rotational movement in bearing 21. Fluid leaves motor 8 within the cylindrical skirt 300 of motor casing 302 and passes through a central passage 14 in intermediate shaft 13, through an opening 15 in bit 3 to wash the borehole bottom 4 and cuttings. When an electric oscillating motor is used instead of a uid motor, inlet hose is coupled directly to bit opening 1S by suitable means.

The washed cuttings are picked up by the iluid and llow around bit 3 into housing 9, in the direction of arrows 16. Motor 8 is suspended in housing 9 from arms 17, resembling a spider (as best shown in FIG. 3), so that the fluid and cuttings can travel between the inside of housing 9 and the outside of motor casing 302 to the entrance of a flexible exhaust hose 18, in the direction indicated by arrows 19. Exhaust hose 18 is fastened to a shelf 20 of housing 9. Shelf 20 prevents the fluid from passing further along housing 9, forcing the uid into exhaust hose 18. Exhaust hose 18 conveys the uid and cuttings to the surface and the drilling operation continues, supplied by a continuous amount of fluid in inlet hose 10.

Bit 3 can have a diamond cutting edge and its oscillating motion grinds borehole bottom 4, so that the cuttings are relatively small and can be carried through a small exhaust hose.

Drilling apparatus 2 is arranged further for continuous drilling by having one or more weighted sections 22, generally referred to as inertia barrels, to maintain the load on bit 3 necessary for maximum cutting effect. Sections 22 are attached to housing 9, preferably by a removable coupling, such as a tool joint (not shown). Inlet hose 10' and outlet hose 18 pass through sections 22 and are provided with

reels

23 and 24, respectively, for storing sufficient hose length to lower bit 3 to a desired maximum depth. The fluid entering inlet hose 10 is at a high pressure, because a pump 25 is connected

intermediate tluid couplings

26 and 27. Fluid enters coupling 27 from a reservoir (not shown) at a low pressure and the pressure is increased in the pump output to coupling 26 which is connected to inlet hose 10. The elongated structure of housing 9 and sections 22 is suspended in borehole 1 by a cable 28 attached at one end to the end section 22 and at the other end to a reel 29. Cable 28 takes the load oif inlet hose 10 and exhaust hose 18 and the cable reel 29 is attached to a drive mechanism (not shown) to raise and lower bit 3 at will.

Cable 28 is provided with insulated electric conductors (not shown) that are used for a purpose to be described and these conductors are connected to

electric lines

30, 31 and 32., respectively, through a cornmutator assembly 33 on ree129.

The seal means can take several forms to carry out its function of substantially sealing olf the borehole annulus 6. The sealing mechanism can be an extendable member inserted between the borehole wall and the drilling apparatus that circumferentially engages the borehole wall and drilling apparatus, or knifes into the borehole wall to seal off borehole annulus 6. Another arrangement is to have the seal means formed by pivotally mounted sections of an annular plate that is forced into engagement with the borehole wall and the drilling apparatus. These embodiments do not normally have freedom of axial movement in borehole 1, which is desirable, although not essential, and the seal means has to be Aretracted to move drilling apparatus 2 any appreciable distance. For this reason I have illustrated an embodiment that substantially seals off the borehole annulus 6 and allows for at least some axial movement in borehole 1 to have continuous drilling without adjusting the seal means. It is apparent that other forms of seal means can perform these functions.

Seal means 5 is supported at the end of housing 9 adjacent bit 3. The fluid and cuttings can enter housing 9 but they cannot go very far into the borehole annulus y6, because seal means S, when closed, presents a substantially complete fluid lock between housing 9 and the borehole wall. The seal or fluid lock is formed by an inflatable tube 35 (FIG. 4), constructed of rubber or other elastic, fluid containing material, that rings or circumferentially surrounds and fits in a recess of housing 9.

Tube 35 has a rectangular vertical cross-section when deilated, one of its longer sides 37 lying against a flat annular face 38 of housing 9 and one of its smaller sides 36 lying against another flat annular face 39 of housing 9. The other smaller side 40 lies against a at annular face 41 of a ring 42 having an internal thread that engages a threaded end 43 of housing 9. Ring 42 can be unscrewed to remove tube 3S. The other longer side of tube 35, generally termed the shoe, has its outer face 44 substantially even with the outer face of housing 9 when tube 35 is dellated. Adjacent ring 42, the corner of tube 35, where the uid first hits, has a projection 45 that is 'beveled towards the borehole wall so that the fluid will tend to increase the pressure of shoe face 44 against the borehole wall. When tube 35 is deflated, as shown in FIG. 4, projection 35 rests against a matching beveled face 46 of ring 42. Tube 35 has an annular central cavity 47.

One of the support arms 17 for motor 9 (FIG. 3) is larger than the other support arrn 17 to allow space for a passage 50 extending between housing face 38 and a surface 51 of support arm 17'. Tube 35 has inlet extension 55 constructed of the same material as tube 35 that lies in passage 50 and has a metal, externally threaded, open end piece 56 projecting above support arm surface 51. End piece 56 has a nut 57 firmly securing tube inlet extension 55 in support arm 17. Secured to support arm 17 in fluid tight relation by fasteners or welding (not shown) is a valve having a housing 59 with a chamber 60 in which tube end piece 56 extends and a second chamber 61 communicating with chamber 60 by a passage 62. Passage y62 has a poppet valve closure member 63 that seats with the uid, biased closed by coil spring 305, and is opened by an electromagnet 64 when energized by a current from power source 122 (FIG. 1) through electromagnet coil having terminal leads 65 and 66. Chamber 61 has an internally threaded aperture that is coupled to an externally threaded end of pipe 67.

The operation of seal means 5, without reference at this point to anything more than the simplest control means, can be pictured by lirst assuming that tube 35 is deflated, as shown in FIG. 4, with a captive, imcompressible iluid 48 in the tube cavity 47, tube inlet extension 55, and

chambers

60 and 61. Valve 80 is opened `by energizing electromagnet 64, withdrawing poppetA valve closure member 63. If there is no pressure in pipe 67 nothing will happen. As pressure is built up in line 67, tube 35 expands because of the increased pressure in tube cavity 47. The only way tube 35 can expand is at the shoe face 44 and as pressure increases furthe-r shoe face 44 engages the borehole wall completely around housing 9 and over a substantial face area. The new shape of tube 35 is represented by dotted lines 71. The fluid and cuttings are deilected by tube side 40 and projection 45 and the borehole annulus 6 is substantially sealed oit. Once tube 35 is expanded, electromagnet 64 can be de-energized, closing valve 80, and tube 35 will remain inilated.

The pressure in pipe 67 that inates tube 35 can come from many sources disposed at a number of locations. For example, the pressure can be controlled by a pressure generator at the surface coupled to pipe 67. The pressure in pipe 67 can be decreased after poppet valve 80 is closed to allow tube 35 to deate a predetermined amount whenever valve 80 is opened, as may be desirable momentarily to move bit 3 in or out of borehole 1. Normally, housing 9 and sections 22 move further into borehole 1 with tube 35 inflated and maintaining a substantial fluid lock as the dril'ing continues.

The pressure in pipe 67 that inates tube 35 is preferably provided by a pressure source mounted on drilling apparatus 2. The pressure source thereby need not trans mit the high fluid pressure required to inflate tube 35 over a long distance. In my preferred embodiment, a pressure transmitter 100 (FIG. 2) is mounted in housing 9 on the other side of shelf 20 from where the fluid and cuttings flow. Pipe 67 passes through shelf 20 in a fluid tight seal (not shown), in the same manner as inlet hose 10, and is connected to a high pressure port 101 in a transmitter housing. One end of the transmitter housing is a cylinder 102 that receives a slidable piston having a head 103 and connecting rod 104 to form a pressure generator. Piston head 103 has means for providing a slidable iiuid seal against the wall of cylinder 102, such as O-ring 105. The volume in front of piston head 103 and pipe 67 contains captive, incompressible tluid 48, that is placed under pressure as piston head 103 moves towards housing port 101.

Connecting rod 104 can be manipulated by any suitable means to control the pressure in pipe 67. For example, an electromagnet or reversible motor can be used. I have illustrated a more sophisticated mechanism which does not require an electric power source, except to energize two valves, and can be operated without any electrical connection, if desired.

In my embodiment, pressure transmitter 100 includes a pressure operated actuator formed by a cylinder 106, at the opposite housing end from cylinder 102, and a piston head 107 having O-ring 108. Piston head 107 is attached to connecting rod 104 to move piston 10'3 and is biased in the opposite direction from piston 103 by a coil spring 109 surrounding connecting rod 104 and engaging a housing ledge 110 and the inner face of piston 107. In this arrangement, piston 107 normally is held against housing end 111 and is motivated in the opposite direction only by a force created by permitting fluid from inlet hose 10 to pass through coupling 112, valve 113, and coupling 114 to a port 115 in housing end 111. Valve 113 has two positions, electrically selected by a current over electric line 116 (the two wires of a conventional electrically controlled valve are shown as one electric line for convenience). One position, called position A, when valve 113 is energized, connects coupling 114 to coupling 112 and the other position, called position B, connects coupling 114 to a vented coupling 117, open at its unconnected end to the air in housing 9 above shelf 20. The f volume on the opposite side of piston 107 from port 115 is continuously vented to the air in housing 9 above shelf 20 by a coupling 118 connected adjacent housing ledge 110.

`The operation of pressure transmitter 100 is controlled from the surface where the fluid pressure in inlet 10 is generated and can be turned on or olic by control unit 120 energizing or stopping `pump 25, respectively. Control unit 120 includes

switches

123 and 124, for example, that can be operated individually or in a desired sequence by activation of control unit 120. For example, switches 123 and 124 can be part of electromagnetic relays, each operated manually and separately by push-buttons. The electric Wires running to the

electromagnet terminals

65 and 66 of valve 80 have been represented as a single electric line 121 in FIG. 2. for convenience, but in actual arrangement a two wire cable is used. One Wire from each of

lines

116 and 121 can be tied together and connected to one of the electric wires in cable 28, mentioned above, and ultimately connected through commutator assembly 33 to line 30. The other two wires, one from valve 113 and one for valve are individually connected to separate wires in cable 28 and ultimately connected to

lines

31 and 32, respectively. Line 30, being the common lead, is directly connected to one side of a power source 112, usually a DC supply, and

lines

31 and 32 are selectively coupled to the other side of the DC supply by

separate switches

123 and 124 actuated at will, either individually or together, by a control unit 120, the sequence depending on the desired operation.

As the drilling apparatus 2 is lowered into borehole 1, pump 25 is de-energized and no iluid flows in inlet hose 10.

Valves

80 and 113 are de-energized (valve 113 is in position B, venting cylinder 106), and tube 35 is deated as shown in FIG. 4. Piston 107 of pressure transmitter is held against housing end 111 by spring 109. Once the drilling position is reached, control unit 120 energizes

valves

113 and 80 by closing

switches

123 and 124, and pump 25 is energized to send a high pressure fluid down inlet hose 10. A part of the uid flows into cylinder 106 and acts against the face of piston 107 which is substantially larger than the face of piston 103, preferably at least four times larger.

The iluid pressure in inlet hose 10 and entering cylinder 107 is not high enough to adequately inflate tube 35 and there is the further problem of bleeding the Huid lines. Pressure transmitter 100 serves to increase the pressure and provides a uniform control with several further advantages. Piston 107 is displaced by the tluid pressure against the force of spring 109 and, and because of the common connecting rod 104, piston is also displaced to increase the pressure of captive fluid 48 in cylinder 102, pipe 67, and cavity 47. The increase in pressure within tube 35 causes shoe face 44 to extend and force against wall of borehole 1 to substantially seal off the `borehole annulus 6. The smaller face area of piston 103 produces a much greater force or pressure than the pressure acting on piston 107. It is apparent that tube 35 will not be inated until there is suicient pressure in inlet 10 to displace piston 107. In other words, there is a predetermined pressure below which piston 107 will not be displaced and there is a predetermined pressurethe normal pressure in inlet lil-Which will displace it completely. The drilling system, including pressure transmitter 100, is designed so that the normal uid pressure in inlet 10 is adequate to expand tube 35 to the maximum expected borehole annulus spacing and tube 35 expands laterally if the spacing is less than the maximum expected.

Once tube 35 is infllated to seal off borehole annulus 6, control unit 120 is operated to de-energize valve 80, retaining the high pressure in cavity 47. Valve 113 can be be de-energized also, venting cylinder 106 adjacent piston 107 to the air. Spring 109 forces out all the liuid in cylinder 106 and

pistons

107 and 103 return to their biased positions. The withdrawal of piston 103 reduces the pressure in pipe 67 to normal. Then valve 80 can be energized and tube 35 will deate, opening the seal. The energization of

valves

80 and 113 can be timed to permit a total or partial deflation of tube 35. The partial deflation can be used to free tube 35 should it happen to become stuck against a projecting part of the borehole wall and it is not desired to completely release the seal.

The actuation of tube 35 need not require the use of valves or any electrical connection to the drilling apparatus 2. For example, control of the Huid pressure in inlet 10 is sufficient to actuate selectively tube 35. Assuming that

valves

80 and 113 are not in the system, i.e. the connections are as if each Valve is energized, with fluid from inlet 10 entering cylinder 106 and tiuid from pipe 67 entering tube 35. When the uid pressure is below a predetermined level, piston 107 will not be displaced. As the pressure is increased, piston displacement occurs and tube 35 is inated at the normal pressure in inlet 10. To deflate tube 35, the luid pressure in inlet 10 is decreased, by turning pump ofi, for example, and piston 107 returns to its biased position after expelling the fluid from cylinder 106.

Other forms of pressure transmitters can be employed to build up the pressure for inflating tube 35, and these pressure transmitters can be controlled in several ways to close or open the seal.

As mentioned above, my invention can be applied to a rotary rig, such as rotary rig 130 shown in FIGS. 8-10, with a few modifications of existing equipment. The conventional derrick 131 (only partially shown) is located above borehole 1 and includes platform 132. The drill string 133 is composed of modified drill pipes 134 and modified drill collars 135 Drill pipe 134 (FIG. 9), including kelly joint 134', has two conduits 136 `and 137, for the inlet iiuid and outlet uid, respectively, formed by the tubular body wall and an 'axially extending partition 138 secured therein. Partition 138 extends into the tool joints on each drill pipe and kelly joint 134', and, when drill pipes 134 and kelly joint 134' are coupled tightly, two essentially continuous conduits are formed. Each drill collar 135 (FIG. l0) has two longitudinally extending and laterally spaced

holes

139 and 140 therethrough that line up, when drill collars 135 are coupled together to provide two continuous conduits. The tool joint between the end drill collar 135 and the end drill pipe 134 provides a separate passage (not shown) connecting one of the conduits in the drill collar 135 to a conduit in the drill pipe 134, and another passage (not shown) connecting the other of the conduits in the drill collar 135 to the other conduit in the drill pipe 134. The end drill collar 135 is coupled to bit 141. The inlet fluid conduit in end drill collar 135 is coupled to la central aperture in bit 141 and the exhaust conduit opens at the lower face adjacent bit 141. Fluid passes from the inlet conduit in end drill collar 135, through bit 141 and forces the cuttings into the exhaust conduit in end drill collar 135.

Drill string 133 is rotated by a kelly 142 yand its associated engine (not shown). The fluid coupling 154 to the kelly joint 134 has a lower portion that rotates with drill string 133 and an upper portion that is stationary. The rotatable joint, which can be similar to the coupling shown in my U.S. Patent 2,345,465, or other types, is

connected through conduits to the respective inlet and outlet conduits of kelly joint 134'. Coupling 154 connects the inlet conduit of kelly joint 134', to inlet hose 150 carried by a swiveled pay-out block 152 suspended by derrick 131. Hose 150 is connected to the fluid pump 153. The exhaust conduit in kelly joint 134' is connected by fluid coupling 154 to exhaust hose 155 also carried by pay-out block 152 and connected to a fluid reservoir (not shown).

The drilling operation for rotary rig 130 follows the conventional procedures, except for the use of seal means 5 supported adjacent bit 141 on end drill collar 135. The mechanical details for seal means 5 can be the same as described above. End drill collar 135 is arranged to mount tube 35 outside and pressure transmitter 100 inside which is coupled to the inlet conduit. Valves and 113 need not be employed and pressure transmitter 100 can be operated by controlling the fluid pressure in the inlet conduit, as described above. Alternately, when

valves

80 and 113 are incorporated, an electric cable can be layed in one of the conduits and a commutator assembly used adjacent coupling 154 to connect `a control means and power supply 122 in the manner described above.

Seal means 5 functions in the same manner on rotary rig to provide a substantial lluid lock across the borehole annulus 6. Drill string 133 moves further into borehole 1 as the drilling continues and seal 5 permits this movement while still retaining the substantial fluid lock.

The drilling apparatus shown in FIG. 1 can be moditied as shown in FIG. 7 to include the yadded feature of retrieving a borehole core as the drilling continues. The surface equipment is the same and the only major change is in the motor 9 and ibit 3. Motor 9 is modied to the extent that the solid drive shaft 11 is replaced by a hollow drive shaft and a tube 176 extends over one end of drive shaft 175 and is mounted in axial alignment in housing 9. The other end of drive shaft 175 is coupled through a coupling 176 having a central opening that connects drive shaft 175 and the shaft end of a bi-t 178. Bit 178 has the conventional cutting teeth 181, preferably diamond edge, and is mounted for rotational movement in bearing 179. The inlet fluid passes from motor 9 through several passages 180 in bit 178, out the lower face of bit 178 to wash the cuttings into the exhaust fluid path through housing 9.

Bit 178 further includes a rigid, axially aligned tube 182 projecting outward from the cutting teeth 181 into Iborehole bottom 4. The far end of tube 182 has a cutting edge 183, preferably diamond studded, for cutting into the e-arth. In this manner the center of the borehole bottom 4 is cored and not drilled. The center of the borehole 1 is the slowest section drilled due to the slow movement of bit 178, so that no appreciable delay in drilling is produced. Tube 182 receives core 184. Core 184 passes through an axial opening in bit 178, into coupling 176, drive shaft 175 and into tube 176. Drive shaft 175 rotates freely within the end of tube 176, tube 176 being stationary and constituting a core storage facility that can extend a substantial distance.

In drilling a large hole, the fluid motor for drilling apparatus 2 (FIG. 1) must be of substantial size. One of the chief problems in enlarging a uid motor which has valve closure members that seat with the fluid, is unseating the valve closure members. A uid motor like the one described i'n my above referenced application can be lmodiiied to facilitate valve unseating. The modification improves the motor operation with'a high pressure, continuously liowing duid, decreasing the chance of a stuck valve closure member. In general, I have provided a means for relieving the pressure against the valve closure member so that the valve closure member can be opened more easily while not inhibiting the closing function. In another respect, I have provided actuator means that moves a distance before engaging the valve closure member with a jar to -dislodge a stuck valve closure member.

A preferred embodiment of a fluid motor 200 having these improvements, is shown in FIG. 5. Motor 200 is arranged in most respects like the motor described in my above referenced copending application, including motor casing 201, fluid inlet pipe 202, drive shaft 203 mounted in bearing 204, motor housing 205 with only the intake block 206 and part of the valve rod block 207 shown. The impeller blade (not shown) is driven by the fiuid entering the motor housing by manipulation of the valve means 208 in the intake block and exhaust block (not shown), as is described in my referenced copending application.

The valve means 208 includes intake poppet valve closure members 209 and 210l and the exhaust poppet valves (not shown), each arranged in the same unique fashion of my invention on their

respective valve rods

211 and 212 for seating with -the fluid pressure in matching valve seats 213 and 214, respectively.

Valve rods

211 and 212 are supported and pass freely through

spiders

215 and 216, respectively, in intake block 206 to prevent lateral movement.

Valve means 208 is manipulated by an actuator means 217 including projection means 218 on drive shaft 203 for oscillation therewith. Projections 218 operate a lostymotion spring-loaded actuator means 219 that, in turn, shifts the linkage means 220 to open an intake valve on one side of the impeller blade (not shown) and the exhaust valve on the other side of the impeller blade, then opening the other intake and exhaust valves, and alternating this sequence with the oscillation of drive shaft 203. Linkage `means 220 is also actuated by an auxiliary valve unseating means 221. All these mechanisms operate as described in my above referenced copending application.

The modification in the valve vmeans 208 that reduces sticking and facilitates opening the valve closure member is best shown in FIG. 6` for poppet valve closure member 209 and valve rod 211. Poppet valve closure member 209 closes fluid passage 225 (FIG. seating with the fluid when valve rod 211 is in one position. A heavy pressure continues to keep valve closure member 209 closed and when valve rod 211 is lifted by the linkage means 217 la very large force is required to counter the fiuid pressure.

I have provided in valve closure member 209 a central passage 226 that, when open, carries fiuid from the face 227 of valve closure member 209 into the motor housing through spider 215. When passage 226 is opened, pressure is relieved on valve closure member 209 and linkage means 217 can unseat valve closure member 209 more easily. Passage 226 has a poppet valve seat 228 that receives a poppet valve closure member 229 that slides freely on valve rod 211, has a smaller surface area face than face 228 and seats with the fiuid pressure. When valve rod 211 is in the position for valve closure member 209 to close, as shown in FIG. 6, valve closure member 229 is seated also.

Valve rod 211 passes freely through `a ring 235 supported in passage 226 from valve closure member 209', by spaced arms 240 that permits fiuid flow therearound. As linkage means 220 moves valve rod 211 to a second position, opening valve closure member 209, valve rod 211 has engaging means, such as collar 230 fixed thereto and spaced between and from valve closure member 229 and ring 235 that jars and unseats valve closure member 229 to permit fiuid to enter

passage

209 and 225. The pressure on valve closure member 209 being relieved, valve closure member 209 is jarred and unseated by an engaging means, such as a collar 231 fixed to valve rod 211 and spaced from ring 235 on the opposite side from collar 230. The spacing is sufficient to develop a forceful jar. As long as valve rod 211 is in the second positionvalve closure member 209 remains unseated.

The arrangement of engaging means and valve rod can take other forms to unseat a relief valve closure member first. Other arrangements of a valve rod and valve closure member can be used to provide a jar at a central location to prevent valve sticking. These features, either together or individually, can be utilized in other devices where valves are employed and for many types of valves.

While I have disclosed several preferred embodiments of my invention, other embodiments could be illustrated and are obvious to one skilled in the art. These other embodiments and changes or modifications in the disclosed embodiments are a part of my invention as defined in the attached claims.

I claim:

1. Apparatus for creaing a hole in the earth, comprising,

means for drilling said hole,

said drilling means having conduit means for Carrying a fluid into and away from the hole to remove portions of the earth from the hole as the drilling is proceeding,

means for preventing said fluid from passing between said drilling means and the hole wall and thereby forcing said fluid to exit only through said conduit means,

said preventing means including a member expandable to close off the passage between the drilling means and the hole wall, said member having a central volume in communication with a fluid line, said fluid being coupled to a piston-operated pressure generator including a first piston and having a captive fluid in said line, said first piston being actuated by a piston operated pressure actuator including a second piston coupled for motivation by fiuid coming into said drilling means, said first piston producing a higher pressure in said fiuid line than said incoming fluid produces on said second piston, first valve means for decoupling said pressure actuator from said incoming fiuid and second valve means for closing off said fluid line, and control means for actuating said first and second valve means to cause selectively said member to contract with or without fiuid coming into said drilling means and to expand selectively said member with fluid coming into said drilling means.

2. Apparatus for sealing a hole in the earth, comprising,

means including an elongated structure to be disposed lengthwise in the hole,

means supported by said structure for substantially sealing off the passage between said structure and the hole wall,

means for controlling said sealing means to open and close said passage at selectable times,

said sealing means comprising an expandable member surrounding said structure,

a piston operated pressure generator including a first piston coupled to said member for expanding or contracting said member to substantially close or open, respectively, said structure-hole passage,

a piston operated pressure actuator including a second piston coupled to a fluid to motivate said first pressure generator, said first piston producing a higher pressure than said fluid acting on said second piston,

first valve means for venting said pressure actuator,

second valve means for retaining the pressure built up in said member,

said control means including electrical circuit means to be disposed at the surface for actuating said first and second valve means to expand and contract said member selectively.

3. Apparatus for drilling a borehole, comprising,

an elongated structure to 'be suspended lengthwise in the borehole,

motor means carried by said structure,

cutting means coupled to said motor and being positioned at the one end of said structure to be disposed in the borehole to remove portions of the borehole when driven by said motor means,

means carried by said structure for sealing the passage between said structure and the borehole, said sealing means comprising an inatable member surrounding said structure, permitting axial movement of said structure in said borehole without adjusting said sealing means when said passage is closed off.

control means for activating said sealing means to close or open selectively the structure-borehole passage,

support means including a cable, and rst and second hoses attached at one end to one end of said structure for carrying fluid into and out of the borehole, respectively, said structure being arranged for suspension in the borehole from said support means cable and supporting said motor means and carrying said sealing means,

said structure having an inlet passage connecting with said rst hose for carrying the uid to the end of said structure where said cutting means is disposed, and having an outlet passage connecting with said second hose for carrying the fluid and removed borehole portions for withdrawal from the borehole,

said cutting means being a bit,

said motor means being an oscillating rotary motor actuated by the duid entering said housing from said first hose, to rotary oscillate said bit, said structure acting as on inertia member for said oscillating, rotary motor, subjecting said seal member substantially only to axial movement in said borehole to force said bit into said borehole.

4. Apparatus, as described in claim 3, wherein,

said bit includes a central, longitudinal opening formed by a projecting tube having a cutting edge at the end to remove a core from the borehole as the bit oscillates and to store the core in said housing.

'5. Apparatus for drilling a borehole in the earth, comprising,

an `elongated structure to be suspended from a cable lengthwise in the hole,

cutting means supported lat one end of said structure to be disposed in said `hole yand comprising an oscillating, rotary motor fand "a bit coupled to said motor,

means Ifor motivating said motor, .to cause said bit to rotary oscillate and remove portions of the earth,

said structure having means for conducting a iiuid to and away from said one structure end to carry away the removed earth portions,

means supported by said structure for substantially sealing ol the passage-between said structrue and hole Iwall adjacent the cutting means and thereby fforcing said iiuid to ow through said structure conducting means, and permitting axial movement of said structure in said borehole for continuous drilling into said earth,

said structure having means acting as an inertia member for said motor and lforcing said bit into said borehole, to permit substantially only axial movement of said seal means as said structure forces said bit into said borehole with said sealing means closing oi said passage.

References Cited UNITED STATES PATENTS 385,60() 7/1'888 Dunbrow 166-1'87 X 597,3116 1/1898 Durbrow 175-215 X 1,484,065 2/ 1924 Gould 175-99 X 2,002,386 5/1'935 Bannister 175--106 X 2,373,005 4/ 1945 Baker 166-122 2,663,545 12/195'3 Grable 17543-25 X $13,587 11/ 11957 Mounce 1-66-187 X 298116,7-35 12/ 1957 Dalinda et al. 175-325 X 2,942,667 6/ 1960 Blood et al. 175-325 X 301,1,554 122/ 1961 Desbr-andes et al. 16d-4100 CHARLES E. OCONNELL, Prm'aly Examiner.

4 I. A. CALVERT, Assistant Examiner.

Claims

1. APPARATUS FOR CREATING A HOLE IN THE EARTH, COMPRISING, MEANS FOR DRILLING SAID HOLE, SAID DRILLING MEANS HAVING CONDUIT MEANS FOR CARRYING A FLUID INTO AND AWAY FROM THE HOLE TO REMOVE PORTIONS OF THE EARTH FROM THE HOLE AS THE DRILLING IS PROCEEDING, MEANS FOR PREVENTING SAID FLUID FROM PASSING BETWEEN SAID DRILLING MEANS AND THE HOLE WALL AND THEREBY FORCING SAID FLUID TO EXIT ONLY THROUGH SAID CONDUIT MEANS, SAID PREVENTING MEANS INCLUDING A MEMBER EXPANDABLE TO CLOSE OFF THE PASSAGE BETWEEN THE DRILLING MEANS AND THE HOLE WALL, SAID MEMBER HAVING A CENTRAL VOLUME IN COMMUNICATION WITH A FLUID LINE, SAID FLUID BEING COUPLED TO A PISTON-OPERATED PRESSURE GENERATOR INCLUDING A FIRST PISTON AND HAVING A CAPTIVE FLUID IN SAID LINE, SAID FIRST PISTON BEING ACTUATED BY A PISTON OPERATED PRESSURE ACTUATOR INCLUDING A SECOND PISTON COUPLED FOR MOTIVATION BY FLUID COMING INTO SAID DRILLING MEANS, SAID FIRST PISTON PRODUCING A HIGHER PRESSURE IN SAID FLUID LINE THAN SAID INCOMING FLUID PRODUCES ON SAID SECOND PISTON, FIRST VALVE MEANS FOR DECOUPLING SAID PRESSURE ACTUATOR FROM SAID INCOMING FLUID AND SECOND VALVE MEANS FOR CLOSING OFF SAID FLUID LINE, AND CONTROL MEANS FOR ACTUATING SAID FIRST AND SECOND VALVE MEANS TO CAUSE SELECTIVELY SAID MEMBER TO CONTRACT WITH OR WITHOUT FLUID COMING INTO SAID DRILLING MEANS AND TO EXPAND SELECTIVELY SAID MEMBER WITH FLUID COMING INTO SAID DRILLING MEANS.