US2877984A - Apparatus for well drilling - Google Patents

Description

March 17, 1959 Filed 111137 26, 1954 o. A. CAUSEY APPARATUS FOR WELL DRILLING 3 Sheets-Sheet 1 CK I 32 M 9/ 28 2a I 26b 4 26 INVENTQR Oiz's H.C' ausey ATTORNEYS O. A. CAUSEY APPARATUS FOR WELL DRILLING March 17, 1959 3 Sheets-Sheet 2 Filed July 26, 1954 .saxu

w w. l u m r NVENTOR Oiis H. C'ausey ATTORNEYS WAAAAA/A? March 17, 1959 o. A. CAUSEY APPARATUS FOR WELL DRILLING S SheetS-Sheet 3 .Fl'ig. 0

Filed July 26, 1954 INVENTOR Ozis H. Causey M will United States This invention relates to well drilling implements or tools, a major object being to provide an air-operated tool unit by means of which a well may be rapidly drilled through soft or hard material.

The drilling mechanism includes members mounted in a starter or drill head and mounted therein for up and down movement as limited by a spider removably secured in the head, and which spider while an essential feature in the mounting and operation of the members, normally forms a bar against removal thereof. It is therefore another object of the present invention to provide for the release and removal of this spider, from the surface so that said members may be readily withdrawn from the drill head and well casing without disturbing the latter.

The drill tool unit includes a central pilot drill, side chisels spaced radially out from the drill, and a jack hammer to actuate the drill and chisels; and a further object of this invention is to arrange the drill and chisels in connection with the jack hammer in such an improved manner that the chisels will only be actuated after the drill has been driven down a predetermined distance relative to the chisels, so that the additional pressure necessary to operate the chisels need not be used if the drill is proceeding in soft ground and no Wear on the chisels is then involved.

A further object is to provide a novel method for counteracting and blocking ofi excessive underground pressures which may be encountered during drilling, so that such pressures will not interfere with continued drilling operations.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings:

Fig. l is an elevation of my improved well drilling apparatus, partly in section and showing the same as initially engaged with the ground or at the start of a drilling operation.

Fig. 2 is a similar view, but showing the side chisels lowered from the driving or starter head of the implement.

Fig. 3 is a fragmentary enlarged sectional elevation of the apparatus, showing particularly the chiselmounting block-and connected parts.

Fig. 4 is a sectional elevation of the structure of Fig. 3, on a reduced scale and transversely thereof, taken on line 4-4 of Fig. 3.

Fig. 5 is a fragmentary enlarged sectional elevation of the apparatus, showing particularly the upper drill-pipe supported block and connected parts.

Fig. 6 is a fragmentary elevation, partly in section, showing the upper block as raised and engaged with the fixed but removable spider, preparatory to the removal of the spider.

Fig. 7 is a sectional plan on line 77 of Fig. 1.

Fig. 8 is a similar view on line 88 of Fig. 1.

Fig. 9 is a fragmentary elevation, partly in section, showing a modified connection means between the starter head as released and lowered from the casing.

atent O i Patented Mar. 17, 1959 Fig. 10 is a similar view, showing the starter head as released and lowered from the casing.

Referring now more particularly to the drawings and to the characters of reference marked thereon, and particularly at present to the structure shown in Figs. 1-8, the apparatus comprises a relatively heavy tubular starter or driving 'head 1, in which all the parts of the apparatus, as hereinafter described, are mounted. This head is substantially the diameter of the well to be drilled, and com prises a straight-bored upper main portion 2 and a relatively short lower portion or extension 3 of the same out side diameter as portion 2 and removably secured thereto,

7 as shown at 4. Extension 3 is provided with a wearresisting liner 5, the bore of which flares somewhat in a downward direction-as at 6and terminates at its lower end in a sharpened lip 7, whose cutting edge is alined with the outer face of the head, as shown in Figs. 1 and 3.

At its upper end the head 1 is rigidly secured to the adjacent length 8 of a string of well casing; said casing extending to the surface and being added to as the drilling progresses, as is customary.

Removably screwed into the head 1 at its upper end is a spider 9 through the central hub 10 of which a pipe 11 slidably and turnably projects. Said pipe is relatively short, and at its lower end is secured in a block 12 which is of oblong form in plan, as shown in Fig. 8, so that while substantially turnably fitting at its ends in the head, the block has wide clearance at its sides from the inner wall of the head.

An enlarged hub or cup 13 on the upper end of pipe 11 normally seats on'the hub 10 and limits downward movement of the pipe and block 12 suspended therefrom. The adjacent length 14 of a string of drill pipe, which also extends to and above the ground surface and above the well casing string, is secured in cup 13.

A tubular air-feed stem 15 extends in clearance relation through pipe 11 and slidably projects through a guide sleeve 16 secured in and depending from the block 12 a certain distance. The stem has an enlarged head 15a on its upper end to limit downward movement of said stem through pipe 11. Said stem 15 projects below the lower end of sleeve 16 and is connected as shown in Fig. 2 to the upper end of a conventional jack hammer 17. The hammer includes a depending axially movable piston 18 non-turnably slidable through a cross bar or plate 19 secured on the upper end of a lower block 20 formed to leave an open space 21 below the cross bar.

downward pressure on the block. Said block is oblong and is arranged at its ends to turnably fit the head member 2, but so that its sides clear the bore of the head considerably as shown in Fig. 4. Since the piston 18 is normally relatively retracted in the hammer, as usual, upward movement of the hammer body will likewise move the piston and head 22 upwardly therewith. A tension spring 24, extending between and connected to the air hammer 17 and the upper block 12, will, therefore, cause the head 22 to be normally held up against the bar 19 as shown in Fig. 1.

A tubular stem 25 depends from piston 18 and through the block 20 below space 21 and carries a diamond-point drill 26 on its lower end, below the cutting edge 7 of the head 1, and which serves as a central pilot during a drilling operation.

Pivoted at their upper end on the block 20 in opposed relation, as at 27, are digging chisels 28, sharp-edged at their lowerend and notched circumferentiallyas at.28a

to form teeth as shown in Fig. 4. These chisels are initially retracted into the head extension 3 and as the lip 7 of said extension enters the ground and the lower edges of the chisels then contact and enter the same, such chisels, as block 20 is lowered, will gradually move laterally out, due to the taper slope of the inner face of the chisels as shown at 28b. When fully lowered, said chisels will project below and radially out from extension 3, so as to cut to a diameter at least as great as that of said extension as shown in Fig. 2. Relatively short immovable breaker chisels 29 are disposed between chisels 28 and depend from the block 2%, and are removably secured in place by pins 30.

Extending between blocks 12 and 2d are opposed telescopic air-passage units each comprising a pipe 31 secured at its upper end in the block 12. and another pipe 32 secured at its lower end in block 20 and extending upwardly into pipe 31 with a close sliding fit; a sealing unit 33 on the lower end of pipe 31 and engaging pipe 32, providing an air-tight unit. Conduits 34 in block 12 (see Fig. extend from the upper end of pipes 31 to communicate with the space between pipe 11 and stem check valves 35 in said conduits being arranged to prevent an upward or back flow of air from the pipes 31. At its lower end, each pipe 32 communicates with a passage 36 (see Fig. 3) drilled through block to discharge therebelow radially inward of the breaker chisels 29, as indicated.

Block 12 at its upper end is provided with upstanding lugs 37 arranged to fit into symmetrically arranged sockets or slots 38 formed in the under side of spider 9 (see Figs. 7 and 8).

In order to indicate to the operator at the surface, the rotated and vertical position of the block 20 and the chisels relative to the casing, the head is provided with a plurality of induction coils 39 spaced 90 apart in a common horizontal plane, and arranged to successively aline with an Alnico magnet 40 set in the block 20 (see Fig. 3). Such alinement sets up a current which may be used to actuate an instrument (not shown) at the surface which will indicate to the operator the position of the block 20 relative to the casing. Similarly, a pair of other induction coils 41, spaced 90 apart, are mounted in head extension 3 for the chisels 28 to successively aline with vertically spaced magnets 42 on such chisels, so that by means of a surface instrument (not shown) actuated upon such alinement being eifected, the operator will know the depth to which the chisels have been lowered from the driving head, or in the event of no alinement and normal actuation of the instrument not being obtained, that a chisel is broken. In order to lead the necessary wiring from the coils 39 and 41 to the surface, the head 1 is grooved on the outside to receive the wiring as shown at 43; the grooves at the upper end of the head terminating in passages 44 which lead diagonally into the casing 8 as shown; such wiring leading thence to the surface for connection to the instruments.

In operation, the assembled apparatus as above described, and with the chisels 28 retracted, is engaged with the ground, and the weight of the apparatus, together with additional pressure if required, causes the drill 26, and the sharp edge 7 of the head 1, to penetrate the relatively soft surface dirt. The dirt displaced by this action is forced to the surface past the blocks and out of the casing 8, by air pressure at relatively low pressure and small volume supplied into drill pipe 14 and feeding thence through the various air pipes and passages to the lower end of the implement below block 20. The volume and pressure of this air is insuflicient to overcome the resistance of the heavy spring 24, and which must be extended and thus loaded if the jack hammer is actuated. Someof this air feeds through passages 36, and some through the tubular stern, which at its lower end has air v dispose the chisels over uncut material.

4 outlet openings 45 and which are then adjacent the bottom of the pilot hole 46 made by the drill 26 as shown.

When hard material is encountered, air at high pressure is fed into the pipe 14 with a volume sufiicient to actuate the jack hammer 17, driving the drill 26 further into the ground. The volume of such high pressure air is calculated to offset the loss of air occasioned by the diversion of some of such air through the passages 36 and the tubular stem 25. When the drill has been thus driven down a predetermined distance, the head 22 engages surface 23, and thereafter the block 20 is also lowered, driving the chisels 28 down into the material :being drilled. This causes such materialwhich has been already weakened by the drill actionto be broken up and shifted toward the center of the hole, where it is pulverized by the breaker chisels 29. With this action, the block 21) and chisels mounted thereon, is given a jack-hammer action, due to the operating connection of the head 22 with the block surface 23 and the pullingup action of the spring 24. When the chisels have depended to the limit determined by engagement of head 15a with cup 13, the air feed is cut off, and the block 20 is lifted somewhat by pulling up on the drill pipe 14, so as to retract the chisels into head extension 3. The drill pipe 14 is then rotated somewhat, which causes a corresponding rotation of blocks 12 and 20, so as to The air feed and jack hammer operation is then repeated, effecting a further drilling operation. While the air is thus being supplied to the jack hammer, a certain amount thereof is also feeding into the bottom of the hole, so as to continuously force the loose material out of the hole and up through the head 1 and casing 8 to the surface.

The extent of lifting of the blocks and parts connected thereto is limited by engagement of the upper block 12 with the underside of spider 9, and when desiring to rotate the blocks for the purpose above described, it is necessary that the upward pull on pipe 14 shall be stopped before such engagement of the block 12 with the spider 9 takes place.

This is because when such engagement is eifected, the lugs 37 non-rotatably seat in the sockets 38. This feature is made use of when it is desired to remove the operating partsincluding the various chisels-from within the head 1 for repair or chisel replacement. The seating of the lugs in the sockets of the spider enables the latter to be unscrewed from head 1 by rotation of pipe 14 in the proper direction, which in turn clears the head of obstructions and allows the spider 9 together with the blocks therebelow, and all parts connected thereto, to be pulled out of the head and easing without disturbing the same. When exposed clear of the well casing, the chisels may be readily replaced, since the retaining pins 27 or 30 are removable and need only be pulled out.

If underground pressures interfere with drilling, the well casing is capped, the amount of such underground pressure is determined, and air at greater pressure is then fed through the casing and into the bottom of the hole to offset and force such underground pressure back into the ground strata from which such pressure is exuding, the-casing remaining capped and the pressure being retained in the well while the drilling proceeds.

If it is found impractical to seal off the well by lowering the casing and drilling head, cement is fed into the bottom of the hole and forced against the exposed wall of the hole by air pressure. This pressure is held against the cement until the latter has set, before drilling is resumed, and the operation is repeated as and if necessary. Under ordinary conditions however, it is not necessary to confine pressure within the casing and head 1 as drilling progresses.

Under certain conditions it may be desired to lower the starter head and tools therein relative to the casing, and to make such head and the tools removable from the casing as a unit without altering the construction of the blocks 12 and 20, the drill pipe 14 and pipe 11, and the connecting parts which extend between said blocks; the starter head and casing connection shown in Figs. 9 and 10 is-employed.

In this arrangement a relatively short depending shoe 47 is rigidly secured to the lower end of casing 8.

Removably screwed at its upper end into the upper end of the shoe, as at 48, for disengagement from the shoe by upward movement, is an extractor ring 49. Removably screwed into the lower end of the ring 49, as at 50, for downward releasing or unscrewing movement relative thereto, is the neck 51 formed on the upper end of the starter head 1a; said neck replacing the spider 9 of the first described type and containing the hub 10a through which the pipe 11 is slidable, and the sockets or slots 38a to receive the lugs 37 on the upper face of the block 12.

, With this arrangement the wiring 52 from the various instrument-controlling coils below (not shown in these views) passes from the head 1a through the interior of the ring 49 to suitable connection with a collector or slip ring unit 53 on the drill pipe 14 adjacent its lower end and from which unit the corresponding wires 54 extend to the surface. The portion of wiring 52 between neck 51 and the slip ring 'unit 53 is provided with sufiicient slack to allow of the necessary vertical movement between the head 1a and the pipe 14.

To withdraw the starter head 1a and the tool unit from casing 8, drill pipe 14 is raised to engage lugs 37 in slots 38a, and said pipe is then rotated in a direction which will tighten neck 51 in ring 49 and then unscrew the ring from the shoe 47; the threads 48 and 50 being cut in the same direction (both right hand or both left hand) so that the above action will be obtained.

As soon as the threads 43 are disengaged, a straight upward pull on the pipe 14 will lift the head 1a and parts mounted therein through and clear of the shoe, permitting the head and drilling unit to be drawn clear of the well.

To enable drilling operations to be continued while leaving the casing stationary, the lugs 37 are again eugaged in the slots 38a, and the drill pipe is then rotated in the opposite direction, or so as to tighten the ring 49 in the casing shoe, and to unscrew the neck 51 from said ring. This will enable the starter head, supported by the drill pipe unit, to be lowered from the casing as much as may be required for continued drilling operations.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention, as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

I claim:

1. A well drilling tool comprising a tubular casingsupported driving head, a spider mounted in the head at the top, a drilling unit below the spider and including an upper block, means suspending the block from the spider for limited vertical movement and including a member above the spider arranged for connection to a vertically movable drill pipe for manipulating the unit from above ground level, a lower block in the head having depending digging members, means connecting the blocks for limited vertical movement of the lower block relative to the upper block andincluding a jack hammer having a depending reciprocating piston, a center drill supported by the piston and projecting through and below the lower block, and connecting means between the piston and lower block allowing of limited vertical movement of said lower block relative to the piston.

2. A tool as in claim 1, in which said last named means comprises a horizontal cross bar on the lower block through which the piston slidably projects, and an enlarged 'head on the piston below the bar and normally engaging the under side thereof; the lower block being formed with a head engaging surface a predetermined distance below the cross bar to allow of a predetermined downward movement of the piston and head before the latter imparts movement to the lower block.

3. A well drilling tool comprising a tubular casingsupported driving head, a spider mounted in the head at the top, a drilling unit below the spider and including an upper block, means suspending the block from the spider for limited vertical movement and including a member above the spider arranged for connection to a drill pipe for manipulating the unit from above ground level, a lower block in the head having depending digging members, means connecting the blocks for limited vertical movement of the lower block relative to the upper block and including a jack hammer between the blocks having a depending reciprocating piston operatively connected to said lower block for reciprocating the same, and a tension spring between the upper block and the jack hammer normally yieldably maintaining the hammer a predetermined distance from the upper block while allowing of downward movement of the jack hammer relative to said upper block.

4. A well drilling tool comprising a tubular casingsupported driving head, a spider mounted in the head at the top, a drilling unit below the spider and including an upper block, means suspending the block from the spider for limited vertical movement and including a member above the spider arranged for connection to a drill pipe for manipulating the unit from above ground level, a lower block in the head having depending digging members, means connecting the blocks for limited vertical movement of the lower block relative to the upper block and including a jack hammer unit operatively engaging the lower block for reciprocating the same, the block suspending means providing air passage means for supplying air to the jack hammer, a telescopic pipe unit extending between and connected to the blocks and providing an open-ended conduit therethrough, passage means in the upper block extending to the upper end of the conduit and placing the same in communication with the air passage means, and passage means extending through the lower block to the under surface of said block and connected at its upper end to the lower end of the conduit.

5. A well drilling tool comprising a tubular casingsupported driving head, a spider mounted in the head at the top, a drilling unit below the spider and including an upper block, a pipe slidable through the spider and connected to the block, an enlarged cup on the pipe above and normally resting on the spider and arranged for connection to an air-feed drill pipe, a lower block in the head and having depending digging members, means connecting the blocks and including a vertical jack hammer unit disposed between the blocks, and having a depending reciprocating piston operatively engaging the lower block to initially support and subsequently impart hammer blows to the latter, an air supply pipe connected to the hammer and slidable through the first named pipe, an enlarged head on the upper end of said air supply pipe and normally above the cup, but engageable therewith to limit downward movement of the jack hammer relative to said upper block, and a spring between the hammer and upper block yieldably holding said hammer up and said head raised from the cup.

6. A well drilling tool comprising a casing-supported tubular driving head, a drilling unit within the head and removable from the upper end thereof, a guide spider mounted in the head above the unit for removal upon rotation of the spider in one direction, an air passage unit including a pipe slidably projecting upwardly through the spider, and a drill pipe projecting upwardly from the first named pipe and arranged for rotation and axial movement from above ground, and means between the drilling unit and spider to lock the two, against relative rotation upon upward movement of the unit a predetermined distance whereby upon rotation of the drill pipe in said direction to then remove the spider to enable the unit to be withdrawn from the head.

7. A tool as in claim 6, in which the spider is threaded into the head and said means comprises a block forming the upper portion of the drilling unit and turnable with the drill pipe, and lugs upstanding from the block; the spider having sockets in its underside to receive the lugs in fitting relation when the block is raised into engagement with said underside of the spider.

8. In a well drilling structure which comprises, with a well casing, a starter head depending from the casing, a rotatable and vertically movable drill pipe Within the casing, means to connect the drill pipe with the starter head for rotation and vertical movement as a unit upon predetermined initial upward movement of the pipe, and means between the starter head and easing normally connecting the head in supported relation from the casing and arranged to enable the starter head to be disengaged from the casing and lowered therefrom upon rotation of the drill pipe and starter head in one direction, and to be disengaged from the casing and lifted inside the same upon rotation of the drill pipe and starter head in the opposite direction.

9. A well drilling structure comprising, with a well casing, a shoe on the lower end of the casing, an extractor ring screwed into the shoe for removal therefrom in an upward direction; a starter head and tool unit depending from the ring, a neck on the upper end of the starter head screwed into the extractor ring for disengagement therefrom in a downward direction, a vertically movable and rotatable drill pipe, and means between the drill pipe and neck to releasably lock the drill pipe against rotation relative to the neck and starter head upon a predetermined extent of upward movement of the drill pipe.

References Cited in the file of this patent UNITED STATES PATENTS 1,461,713 Gilman et a1. July 10, 1923' 2,345,024 Bannister Mar. 28, 1944, 2,485,098 Johnson Oct. 18, 1949 2,544,979 Brokaw et al. Mar. 13, 1951 2,559,012 Davis et al. July 3, 1951 2,626,778 Lockett Jan. 27, 1953 2,675,082 Hall Apr. 13, 1954

Images