US3444937A

US3444937A - Boring apparatus with valveless impactor

Info

Publication number: US3444937A
Application number: US644395A
Authority: US
Inventors: Henry G Warrington; George C Manning
Original assignee: Vulcan Iron Works Inc
Current assignee: Vulcan Iron Works Inc
Priority date: 1967-06-07
Filing date: 1967-06-07
Publication date: 1969-05-20
Anticipated expiration: 1986-05-20

Description

y 1969 H. G. WARRINGTON ETAL 3,444,937

BORING APPARATUS WITH VALVELEISS IMPACTOR Filed June '7, 1967 FIG! INVENTORS' HENRY G. WARRINGTON GEORGE C. MANNING yew United States Patent 3,444,937 BORING APPARATUS WITH VALVELESS IMPACTOR Henry G. Warrington, Palm Beach, and George C. Manning, Riviera Beach, Fla., assiguors to Vulcan Iron Works Inc., Chattanooga, Tenn., a corporation of Illinois Filed June 7, 1967, Ser. No. 644,395 Int. Cl. E21b 1/06, 5/00 U.S. Cl. 175-92 8 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to a method and apparatus for drilling or boring; and particularly for boring into rock or other frangible material commonly found in the earth.

An object of the present invention is to provide a new and improved boring apparatus combining the attributes of percussion boring and rotary boring.

Another object of the present invention is to provide a new and improved boring device for use in a borehole. Another object of the present invention is to provide a new and improved apparatus for boring into rock or other frangible material commonly found in the earth.

Yet another object of the present invention is the provision of a new and improved method of boring into rock or other frangible material commonly found in the earth. Further objects and advantages of the present invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

In accordance with these and many other objects of the present invention, there is provided an improved boring device for drilling or boring into rock or other frangible material and including a drill head for carrying suitable cutter bits and having a portion defining an impact pintle. A fluid actuated impactor is positioned to impart percussion impacts on the pintle while the drill head is simultaneously rotated. Thus the invention combines the attributes of percussion drilling as well as those of rotary drilling.

The invention also relates to a new and improved method of boring or drilling into rock or other frangible material and including the steps of rotating a drill head carrying a plurality of cutter bits in a borehole and simultaneously imparting percussion impacts to the drill head.

For a better understanding of the present invention reference may be had to the accompanying drawings wherein:

FIG. 1 is a cross sectional view of an improved boring device in its operative position in a borehole; and

FIG. 2 is a fragmentary cross sectional view of the boring device of FIG. 1 illustrated with the ram of the impactor in a different operative position.

Referring now to the drawings there is illustrated an improved drilling or boring device 10 according to the present invention and positioned within a driven pile 11 in the earth 12. The drilling or boring takes place beyond the lower open end 11a of the pile 11.

To provide for the drilling and impact, there is provided a drilling head 15 having a stepped lower surface 150. Conventional cutter roller bits 16 are radially located on the steps of the drilling head. Internal passages 17 in the drilling head 15 serve to supply lubricant such as bentonite to the roller bits 16 as they rotate. Additionally the hentonite provides a sealant to enter any interstices which may occur or which are existent in the walls of the hole being drilled. The upper end of the drill head 15 defines an impact pintle 18 for receiving percussion blows.

To provide the percussion blows to the drill head 15 there is provided an impactor 20 including a housing 21 defining a cylinder and having an impact ram or piston 22. The impactor 20 may be of known design and, in the illustrated embodiment, is of the valveless type having the single moving part forming the ram 22. The ram 22 is a differential diameter member having a lower ram portion 22a and an upper piston portion 22b of larger diameter. Motive fluid such as steam or compressed air enters through a fluid inlet 23 into a fluid chamber 24 acting on the area of the piston differential to the diameters of the ram portion 22a and the piston portion 22b to drive the ram 22 upwardly, as viewed in FIG. 1. The upward movement of the ram 22 uncovers a transfer port 24 in the wall of the cylinder communicating to a transfer passage 25 into a chamber 26 defined between the ram 22 and the cylinder head 27. The upward travel of the ram 22 is also effective to close an exhaust port 28 from the chamber 26.

From the above description, the operation of the impactor is believed clear. However, briefly, the impactor is of known type wherein the fluid pressure acting on the differential area between the ram portion 22a and piston portion 22b will drive the ram 22 upwardly from the position illustrated in FIG. 1 to the position illustrated in FIG. 2. Initial upward movement of the ram 22 will close the exhaust port 28 and open the transfer port 24 so that pressurized fluid may now enter through the transfer passageway 25 into the chamber 26 above the piston portion 22b. Since the area of the piston portion 22b opening into the chamber 26 is much greater than the differential area between the piston portion 22b and the ram portion 22a, the buildup of fluid pressure in the chamber 26 will drive the ram 22 downwardly to provide a percussion impact against the impact pintle 18 of the drill head 15. Downward movement of the piston portion 22b is effective to open the exhaust port 28 and to recycle the tool.

The impactor 20 is vertically attached to the drilling head 15 by mechanical means such as a plurality of drill head bolts 30 and cushioned therefrom by a spacer 31 of urethane or other suitable material defining a cushion pad of resilient material.

Rotational movement can then be transmitted to the drill head 15 through the casing 21 of the impactor 20 by means of a drive or square Kelly bar 35. A pressure fluid conduit 36 extends through the inside of the Kelly bar 35 and is connected to the fluid inlet 23 ofthe impactor 20. Additionally a conduit 37 extends through the inside of the Kelly bar connected to supply the bentonite drilling fluid to the passageways 17 in the drill head 15. The hollow interior of the Kelly bar also serves as an exhaust for the spent motive fluid coming from the port 28. The pressure and drilling fluids are rotatably admitted to the

conduits

36 and 37 at the top of the Kelly bar in a known manner by means of a tiered pair of swivels. A conduit 38 also exhausts into the hollow interior of the Kelly bar to provide air relief to the impactor ram 22.

The entire drilling machine assembly is contained within a cylindrical sleeve 40 interposed between the drilling head 15 and a head cap 41. The entire assembly is held 3 together in the vertical by a plurality of radially placed post-tensioned cables 42 attached to the drilling head and passing through and secured to the head cap 41.

Advantageously the present invention combines the attributes of percussion drilling as well as those of rotary drilling. The drilling operation may be performed as a dry hole operation or submerged in water. This type of drilling machine permits drilling beyond the limiting duct of the pile, caisson or sleeve. The impactive speed and rotational speed are independently variable and not coupled or dependent one upon another. A valveless type of impactor has only a single moving part. The control of the impactor is accomplished by change in the motive fluid pressure. The cable method of assembly provides quick disassembly and access to the impactor for service. The ingress of drilling fluid above the drilling machine provides suspended egress of the drilling waste and places the material available for airlift removal.

A specific embodiment of the invention was designed and specified to operate on compressed air having a delivery of temperature of 400 F. thus inducing a thermosetting reaction in the bentonite drilling fluid to force closure and sealing of the walls of the hole so drilled. Moreover thermo-set bentonite drilling fluid sealing and lining the hole so drilled is acceptable as form material for concrete poured therein after the hole has been drilled.

By its nature and concept, there is no theoretical limit to the diametric size of the holes to be bored. The hole size may be increased in diameter merely by changing the drilling head.

The present invention also relates to an improved method of boring a hole into rock or other frangible material found in the earth. More specifically the improved method includes rotating a drill head carrying a plurality of radially disposed cutter bits, and simultaneously applying percussion impacts to the drill head so as to obtain the combined attributes of percussion drilling as well as those of rotary drilling.

Although the present invention has been described by reference to only a single embodiment thereof, it will be apparent that numerous other modifications and embodiments will be devised by those skilled in the art which will fall within the true spirit and scope of the present invention.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. An improved boring device for use in a borehole comprising:

a rotary drill head having a portion defining an impact pintle and adapted to carry a plurality of cutter bits;

a valveless type impactor for imparting percussion impacts on said impact pintle including:

a housing defining a differential diameter cylinder closed at the top,

a differential diameter ram reciprocally positioned in said cylinder including an upper piston portion and a lower ram portion of reduced diameter,

inlet means for introducing fluid under pressure between the two portions of said piston,

exhaust means for said closed end of said cylinder including a port opening into the cylinder side wall positioned to be closed when said piston moves upwardly, and

fluid passage means communicating with the closed end of said cylinder and including a port in the side wall of said cylinder positioned to be opened and placed into communication with said inlet means when said piston moves upwardly;

means interconnecting said drill head and said impactor housing; and

means for transmitting rotary motion to said drill head.

2. A boring device as set forth in claim 1 wherein said drill head has a stepped lower surface for carrying said plurality of cutter bits.

3. A boring device as set forth in claim 1 including a plurality of cutter bits carried on said stepped lower surface.

4. A boring device as set forth in claim 1 wherein a cushion pad is positioned between said housing and said impactor.

5. A boring device as set forth in claim 1 wherein said drill head is carried at the lower end of a drill sleeve and said impactor is within said drill sleeve.

6. A boring device as set forth in claim 1 wherein the last mentioned means is a square Kelly.

7. A boring device as set forth in claim 1 and including means for supplying a drilling fluid to said drill head.

8. An improved boring device for use in a borehole comprising:

an impactor including a fluid actuated ram positioned for imparting percussion impacts on said impact pintle;

means interconnecting said drill head and said impactor;

a square Kelly for transmitting rotary motion to said drill head;

means for supplying a drilling fluid to said drill head, said means including conduit means in said square Kelly; and

additional conduit means provided in said square Kelly for supplying motive fluid to said impactor.

References Cited UNITED STATES PATENTS 848,107 3/1907 Karns -418 X 1,083,666 1/1914 Cook 175-415 2,033,527 3/1936 Kitching 17592 2,815,932 12/1957 Wolfram 175-418 X 2,823,013 2/1958 Stenuick 1755418 X 2,873,093 2/1959 Hildebrandt 175-92 3,050,033 8/1962 Carey 17592 X 3,151,687 10/1964 Sato et a1. 175-95 X 3,236,318 2/1966 Burdine 175-106 NILE C. BYERS, JR., Primary Examiner.