US2667144A - Rotary and impact tool - Google Patents

Description

`Fam. 26, 1954 Filed NOV. 2l, 1949 HI.; "J1 50 S. EVANS ROTARY AND IMPACT TOOL l 2 Sheets-Sheet l Sei/7 Evans INVENTOR.

Way-KM AroRNEY Jan. 26, 1954 5 EVANS ROTARY AND IMPACT TOOL.

2 sheets-sheet 2 -Filed Nov. 21, 1949 1N V EN TOR.

ATTORNEY Patented Jan. 26, 1954 ROTARY n AND IMPACT TOOL Seth Evans, Houston, Tex., assignor to Hughes Tool Company, Houston, Tex., a corporation of Delaware Application November 21, 1949, Serial No. 128,654

15 Claims.

This invention relates to an impact tool and more particularly to a fluid actuated device especially adapted to use in forming earth bores such as oil and gas wells by the rotary method of drilling.

While the description of the invention hereinafter is directed primarily to the drilling of wells, it is to be understood that the invention is not confined thereto, but may be used wherever energy is desired in the form of impacts to accomplish a given purpose.

When drilling wells by the rotary method of drilling, a bit is secured to the lower end of a tubular drill string. While this drill string and bit are rotated, with the bit on bottom, fluid is pumped downwardly through the drill string and out through the bit to eiect cooling thereof and to carry the cuttings removed from bottom upwardly within the well bore. Frequently, pressures of many thousands of pounds are applied to the bit to induce cutting action upon bottom and, particularly Where earth strata are inclined, there is a tendency for the well bore to deviate from the vertical. Furthermore, great diculty is experienced in drilling in some extremely hard formations, such as chert and the rate or drilling in such formations is extremely slow.

It is a primary object of the invention to facilitate drilling and to overcome difficulties as above indicated and others that are experienced when using conventional apparatus and techniques.

Another object oi the invention is to provide a device capable of imparting impact energy to a rotary earth boring drill so that combined action of rotation and impact will effect drilling.

Another object is to provide an impact tool that will produce impacts at a rapid rate so that arelatively large amount of energy may be supplied for action, but Without excessive energy per stroke.

It is also an object to provide an impact tool having a wide range in length of stroke whereby the tool may be readily maintained in operathig position.

Still anotherobject is to provide a tool in which the range of pressure iluctuation is small whereby loss of energy and destructive effects upon equipment are minimized.

The invention also comprehends the provision of a combination rotary and impact tool capable of drilling a straight hole, or of straightening hole theretofore produced and deviating from the vertical.

l Still another object is to provide, in one form of the invention, an impact tool having a piston actuated by pressure fluid pumped downwardly to the tool and cooperating means ior intermittent admission or pressure fluid to the piston and intervening isolation of the piston from the pumped fluid so that the return stroke of the piston is unaffected by the fluid pumped during the period of isolation.

A still further object is to provide means for successively admitting pumped uid to the operating piston and isolating the piston from the fluid being pumped and means for storing energy for the succeeding stroke during the period of isolation.

The foregoing objects, together with other objects and advantages of the invention, will be more fully apparent from the following description considered in connection with the accompanying drawings in which:

Fig. 1 is an elevational View, partly in section, showing one form of the invention;

Fig. 2 is an elevational view, partly in section,

showing the accumulator used in connection with the structure shown in Fig. 1 and comprising an upward continuation thereof;

Fig. 3 is a detail showing one form oi the valve structure of the device, parts being shown in their relative positions at the beginning of the downward stroke of the impact assembly;

Fig. 4 is a view similar to that shown in Fig. 3, but shows the relative position of parts when the impactassembly is in its lower-most position;

Fig. 5 is a detail sectional view showing alternate form of piston and valve actuating mechanism;

Fig. 6 is a detail showing a still different form of the piston and valve actuating mechanism.

A form of the invention is shown in Figs. l and 2 as comprising a body l having a cone type of bit 2 attached to the lower end thereof. The

body l is threaded internally at 3 for engagement with complementary threads on the lower end of a drill string, or the threads 4 of the accumulator, when used, shown generally at E andv opening to receive the barrel i4 having passage l5 so that a stream of pumped fluid may pass downwardly into the chamber I5 and thence through the flushing passages in the bit 2.

Attention is directed to the fact that the barrel Ill ts slidably within the spider II and has collar I5 secured thereto and resting upon an annulus II of resilient material, it being intended that this structure shall be capable of resisting shock and at the same time providing a fluidE seall between the barrel and the spider.

A valve ts slidably within the body I and the lower end thereof is provided with a seating;

surface 2l adapted to engage the complementary valve seat 22 on the interior of the body. Similar'- ly, the upper end of the valve 2ilh'as a valvesurface 23 adapted to engage the complementary seat 24 on the nether side of the spider I I. The valve is shown in engagement with this seat. in Fig. 4 and when in such position, passage I3 is closed to flow of iluid downwardly therethrough.

Slidably mounted within the body I and below the valve seat 22, is an annular piston. 25.- having inward projection 25 near its lower end, there being a seal between this projectionandthebarrel I4 to prevent leakage of fiuid past thepistonat this point. It is apparent that the piston 25 thusforrns the bottom of an annular piston cham-- ber I9.

The piston 25 terminates at its upper end in c. plurality of leaf spring elements 2l, each being bifurcated at its upper end to receive valve actuating roller 28 mounted on pin 29 passing through these bifurcations. The rollers 28 are adaptedto ride upon the inwardly converging surfaces 35 and 3| on the inwardly extending ribs 32 on the valve 20. As the piston assembly moves downwardly from the position shown in Fig. 3 and as the rollers 28 pass over the crest formed by the surfaces 30 and 3i, the valve 20, under the iniiuence of leaf springs 2l, is caused to move upwardly so that it will. engage the valve seat 26, whereupon the piston 2G is isolated from fluid being pumped downwardly through the drill string and in the direction indicated by the arrows 52 in Figs. 1 and 2.

As above indicated, closure ofthe valve 2Il'upon its seat 2l! terminates ilow of iiuid through the passage I3 so that continued. flow is maintained only through thev barrel I4. Quite obviously, this condition tends to produce pulsations in the hydraulic system. To minimize this condition and to store energy proximate the device to be used in a succeeding stroke, I provide the-accumulator 5 which, as above explained, comprises body-extension 5 threaded at 4 and I for connection, re-Y spectively, to the body I and the drill pipe with which the device is used. The annular piston within the extension 5 fits slidably within thering 36 mounted in the extension proximate breather openings 3l. These openings permit liquidto freely ow to and from the space 38 above the piston 35.

The piston 352carries a ring 33 engaged byonel or more compression springs shown as 40, 4I- having their opposite ends in abutment with collar 42 secured in the extension 5 by suitable means such as the snap retainerring 43. A protective sleeve or liner 44 is secured to the collar l2 and extends downwardly therefrom to confine the movement of springs 4U and 4I to the annular space 45 between such seeve and the extension It is to be noted that the piston 25has a downwardly facing shoulder [l5 which engagesy the upper end of a compression. spring 4l.; Theopposite. end. of'v this spring: is in engagement.. with disk; or'Bellevillaspring dlunderlying a shoulder:

49 on the interior of the body I. The disk spring is held in place against the shoulder 49 by collar 50 threadably secured in the lower end of the body I. The lower end of the disk spring 48 is engageable by the arcuate shoulder 5I on the piston 25 whereby the assembly just described is resiliently decelerated and brought to rest at an upwardlimit of travel asl will be" more fully described. hereafter.

The piston 25 has inwardly extending projections 55 which move in close contiguity with the outer surface of the barrel I4. These projections are capable of engaging the ring 56, reciprocable for. a limited distance on the surface of the barrel I4, andwhich is held in an uppermost position by the spring 57i' having its lower end in abutment with thering. 53 resting on an upwardly facing shoulder on the barrel. This arrangement serves asa. bumper for the piston 25 in event the tool is held in a suniciently elevated position that the piston 25 tends tomove downwardly beyondthe pointof. engagement of the projections 55 withthe ring 55.

There is a splinedconnection 52. between. the piston 25 and the body I so that reciprocatory movement may be had therebetween, but at the same time, rotary driving actionby the bodywill be imparted to the piston and the bit 2 secured thereto. This enables rotation of the bit inl thev manner well-known in the rotary method, of drilling.

In further explaining. the operation of the device, thus far described, it will be noted that thev spring l'i normally holds the piston 25 in an uppermost position with the, shoulder 5I on the piston inengagement with` the disk spring'd. Thevalve 25 is then in its lowermost position; shown.

in each of Figs. land 3 and fluid pumped downwardly, as indicated by the arrow 5.2,4 will exert pressure upon, and eiect downward movement of,

the piston 25. This will causey the bit 2 to ad. Vance and effect a desired impact upon the surface to be disintegrated. It is understood, ofy

course, that rotative effort will simultaneously be applied to the drill stem, to which the device4 is attachedso that cutting action from both rotation and impact will be effected.

As the piston 25approaches its lowermost position the rollers. 25, ride over the crests formed at the meeting of converging surfaces 30 and 3.I. on the respectivev ribs 32 on the valve 29 whereby an upward component of force is exerted on the valve which then moves upwardly so that the seating surface 23 on the valve, engages the. seat 24 whereby the admission of fluid to the piston.25 is cut-off.

The movement of the valve upwardly uncovers ports 53 in the body I and such ports serve as exhaust openings for the fluid from above the piston 25 as itv moves upwardly toward its uppermost position under the influence of thel spring lll. It is` to be understood. that, prior to the initiation of the return movement of the piston. 25, the desired impact of the bit 2. on bottoinhas taken place.

As the piston 25 rises, the rollers 28 initially ride upon the surface 3I- and thence upon the surfaces 3D, whereby a downward force is exerted on the valve 2B which moves the valve' downwardly, closes the ports 53 and thereafter engages the seat 22, whereupon the component parts of the, assembly are in the initially assumed position o1'. Fig. 3.

The influx of fluid above the piston 25;- effects deceleration. of.` the;y piston and` associated parts of the piston-and-bit assembly and the upward movementl of the piston is finally terminated by engagement of the shoulder 5I with the disk spring 48. This spring absorbs kinetic energy from the piston and thus prevents shock that would otherwise result. Also, the energy absorbed by the disk spring is returned to the piston assembly as the succeeding downward stroke, above explained, is initiated.

It is also to be understood that when the accumulator 5 is used, the piston 35 thereof moves upwardly after the valve 29 engages the seat 2-4, and in this manner energy is restored in the spring or springs, i8 and il so that luiddisplacement will subsequently take place from downward movement of the piston 35 to transfer the stored energy to the piston on the succeeding downward stroke of the latter.

An important feature of the invention resides in the fact that the device is capable of effecting a relatively large range of length of strokes. In devices in accordance with the invention, it has been found that stroke lengths from one and one-fourth inch to two and one-fourth inches can be had and are extremely effective. For such a range of stroke lengths, the splined connection 52 should be in the neighborhood of two and one-half inches, and for such illustrative dimension, the tool should be so held that the bit is between one and one-fourth inch and two and one-fourth inches, maximum, off bottom during drilling. This range of oif-bottom distance enables ease of control in lowering the tool and drill string at the proper rate to obtain most effective cutting action.

In the form of the piston and valve mechanism shown in Fig. 5, the piston is shown at 25 and has paired upstanding ears 60 to receive pivot pin 6i upon which bell-crank 62 is adapted to rock. This bell-crank lever is bifurcated at its upper end and carries the roller 23 upon pin 29 so that the roller rides upon the rib 32' on the valve 20. The rib 32 on the valve is slightly modied from that previously described in that the inwardly converging surfaces and 3l merge into a ilat inner surface E3. This feature causes a slight delay in the movement of the valve from a given terminal position and hence provides a somewhat greater stroke of the piston.

The bell-crank lever E2 is constantly urged in a clockwise direction by a collar 64 slidably surrounding the barrel Ell and pressed upwardly by the spring 65, having its lower end resting upon the shoulder $5 on the inner periphery of the piston.

The port 53' for the exhaust of uid from above the piston 25', when the valve 2D is in its uppermost position, communicates with a passage 61 in the wall of the body I, and this passage preferably terminates inwardly below the seal 26 so that the exhausted fluids pass downwardly through the conventional ushing passages in the bit 2 to clean and cool the cutters thereon and also to impinge upon the bottom of the hole and thus assist in disintegration of the bottom.

In the modiiication shown in Fig. 6, the valve 20" has inwardly extending webs 'l0 which carry an integral sleeve 'il on their inner ends. This sleeve has ribs 32, each of which is engaged by a roller 28 carried by a bell-crank lever 62 mounted on a pin di carried by the piston 25" which has an annular groove 12 to receive springs 'i3 which constantly urge] the actuator rings I4 upwardly, whereby the bell-crank levers 62' are urged in a counter-clockwise direction and the rollers 28 are held in engagement with the ribs 32". This form also utilizes a spring 'I which engages a shoulder 15 on the barrel I4 and the lower end of the sleeve 1I. The compressive force exerted by this spring supplements the upward component of force exerted on the valve 2U by the rollers 28 riding upon the surfaces 3|" of the ribs 32".

Broadly, the invention comprehends a fluid actuated impact tool capable of effecting both rotary and impact action to disintegrate earth formations and to thereby form bore holes in the earth.

The invention claimed is:

1. An impact device comprising, a body adapted to be attached to the lower end of a drill pipe and having at least one port between the interior and exterior thereof, a baiile in said body above said port forming an annular passage axially of the body, a piston mounted to reciprocate within the body and forming the bottom of a chamber below said baille, an annular valve slidably mounted in the body and movable to alternately close said port and said passage, whereby pumped iluid is intermittently directed to and from said chamber.

2. An impact device comprising, a body adapted to be attached to the lower vend of a drill pipe and having at least one port between the interior and exterior thereof, a baiile extending transversely of the body above said port and forming an annular passage within the body and above the port, a piston mounted to reciprocate within the body below said bafe thereby forming a chamber in the body above the piston, a valve seat on said baiiie, a second valve seat within the body below said port, and an annular valve slid-v ably mounted in the body and movable to alternately engage said seats to open and closel said passage and said port so that fluid pumped into the body is intermittently directed to and from said chamber.

3. An impact device comprising, a body adapted to be attached to the lower end o-f a drill pipe and having at least one port between the interior and exterior thereof, a baffle extending transversely of the body above said port and forming an annular passage within the body, a barrel secured in said bailie and extending downwardly, said barrel providing a iiuid by-pass from above the baffle to a point therebelow and forming, with the body, an annular chamber, an annular piston mounted to reciprocate within and forming the bottom of said chamber, and an annular valve slidably mounted in the body and movable to alternately 'close and open said passage and port respectively so that fluid pumped into the body is intermittently directed to and from said chamber.

4. An impact device comprising, a body, adapted to be attached to the lower end of a drill pipe, a piston in said lbody, a valve seat within the body, a valve movable to and from said seat, said valve including opposed camming surfaces thereon, and means carried by the piston and engageable with said camming surfaces for moving said valve to and from said seat so that pumped iluid is alternately applied to and discharged from above the piston.

5. In a iiuid operated impact tool wherein a piston is normally resiliently urged upwardly within the tool body counter to the direction of movement of actuating pressure fluid the improvement comprising, means for alternately adademas mitting: pressure fluid to; the pistoni and isolating the pistonfromthe pressure fluid, means for exhausting fluid from above the piston during the periods` of isolation, and additional means for storing pressure fluid` energy supplied during the periods of isolation.

6. An impact tool comprising a body, a piston therein, resilient means normally biasing said piston to an uppermost position, means for alternately admitting pressure fluid to and from the chamber above the'piston, and additional means for resilient engagement by the piston at the end of'itsupward stroke tov absorb energy therefrom and thereafter accelerate the piston in a downward direction at the beginning'of the succeeding downward stroke.

7. An impact tool comprising a body, a piston therein, means for producing reciprocatory movement of the piston from fluid pumped, downwardly into the body, and means for decelerating the piston proximate the end of. its upward stroke and thereafter accelerating the piston at the beginning of the succeeding downward stroke.

8. An impact tool comprising a body, a piston therein, means for producing reciprocatory movement of the piston from fluid pumped downwardly into the body, means for decelerating the piston proximate the end of its upward stroke and thereafter accelerating the piston at the beginning of the succeeding downward stroke, said last mentioned means comprising a disk spring mounted within the body, and an abutment on the pistonv engageable thereby.

9. 1n combination, a fluid actuated impact device, including a piston and means for intermittently admitting fluid to and exhausting fluid from above the piston, and an accumulator connected to said impact device to absorb energy from the uid stream, during the period the piston rises for a succeeding stroke.

10. In combination, a fluid actuatedv impact device including, a piston and means for successively admitting fluid ilow to the pist-on and isolating the piston from the fluid flow, and an accumulator connected to the impact device to absorb energy from the fluid stream during the period the piston rises for a succeeding stroke.

11. A device of the class described comprising, a body adapted to be attached to the lower end of a drill pipe, a piston therein, means for successively admitting uid flow to and isolating the piston from fluid ow downwardly through the drill pipe, an upward extension on said body, and means in said extension for successively absorbing and releasing energy of the fluid stream to minimize pulsations in the stream as said first mentioned means successively isolates and admits fluid flow to the piston.

l2. A device of the class described comprising, a body adapted to be attached to the lower end of a drill pipe, a piston therein, means for successively admitting fluid ow to andl isolating the piston from fluid flow downwardly through the drill pipe, an upward extension on said body. and means in said extension for successively absorbing and releasing energy of the fluid stream to minimize pulsations in the stream, said last mentioned means including an annular piston having its opposite sides subjected respectively to the fluid pressures interiorly and exterorly of the body.

13. In a device of the class described, a body, a piston reciprocable therein, spaced Valve seats within the body, a valve slidable axially of the body to alternately engage said seats, converging surfaces on said valve and extending longitudinally thereof, and a spring pressed element carried by the pist-on and riding upon said surfaces so that the valve is urged from seat to seat as the element rides alternately upon said surfaces.

111. In aV device of the class described, a body, a piston reciprocable therein, spaced valve seats within the body, a valve slidable axially of the body to alternately engage said seats, radially extending ribs on said valve, converging surfaces on the free edge of each of said ribs, and means carried by the piston to alternately apply a resilient pressure upon said surfaces so that the valve is urged from seat to seat.

15. An impact device comprising, a body adapted to be attached to the lower end of a drill pipe and having at least one port between the interior and exterior thereof, a baille extendingl transversely of the body above said port and'forming an annular passage within the body and above the port, a piston mounted to reciprocate within thev body below said baffle thereby forming a chamber in the body above the piston, a valve seat on said baille, a second valve seat within the body below said port, an annular Valve slidably mounted in the body and movable to alternately engage said seats to open and close said passage and said port so that fluid pumped into the body is intermittently directed to and from said chamber, and means forming a fluid by-pass from above the baille to a point therebelow to by-passy a portion of the pumped fluid.

SETH EVANS.

References Cited in the le 0f this patent UNITED STATES PATENTS Number Name Date 910,447 Bant et al 1 Jan. 19, 1909 1,087,632 Benjamin Feb. 17, 1914 1,132,063 Bordeen Mar. 16, 1915 1,892,517 Pennington Dec. 27, 1932 2,359,147 Mertenr Sept. 26, 1944 2,390,646 Hays Dec. 11, 1945 2,422,031 Merten June 10, 1947 2,424,108 Merten July 15, 1947 2,507,585 Bassinger May 16, 1950

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