US2890861A

US2890861A - Underwater geophysical prospecting

Info

Publication number: US2890861A
Application number: US479186A
Authority: US
Inventors: Carl V Cook
Original assignee: Phillips Petroleum Co
Current assignee: Phillips Petroleum Co
Priority date: 1954-12-31
Filing date: 1954-12-31
Publication date: 1959-06-16
Anticipated expiration: 1976-06-16

Description

June 16, 1959 c. v. cooK UNDERWATER GEOPHYSICAL PBOSPECTING 2 Sheets-Sheet 1 Filed Dec. 31, 1954 WIRES TO CHARGE FIG.

IN VEN TOR.

GO-DEVlL ROD c .v. coon A TTORNEVS June 16, 1959 c. v. COCK 2,890,861

\ UNDERWATER GEOPHYSICAL PROSPECTING FIGJO BY;- 69 2 A 7' TORNE V5 2,890,861 Patented June 16, 1959 fiice UNDERWATER GEOPHYSICAL PROSPECTING Carl V. Cook, Bartlesville, kla., assignor to Phillips Petroleum Company, a corporation of Delaware Application December 31, 1954, Serial No. 479,186 2 Claims. (Cl. 255-61) This invention relates to geophysical exploration under water. In one aspect it relates to apparatus for and a method of preparing cavities or holes under a body of water for receiving an explosive charge for geophysical exploration. In still another aspect it relates to a method for boring holes and placing explosive charges below a body of water wherein a marker is allowed to remain which does not interfere with off-shore fishing operations. In yet another aspect it relates to an improved knock-off bit, and adapter assembly for use in drilling in under water geophysical exploration operations.

In prior art operations for off-shore geophysical exploration it is the practice to drill a number of shot holes,

for example, from 40 to 50 holes, in advance of the shooting crew of men who shoot the explosive charges in the holes. When holes are drilled with or without placing of the explosive charges prior to operation of the shooting crew, it is necessary to leave markers in order that the shooting crew can locate the holes. Common practice has been in the past to leave drill tubing in the hole and extending above the surface of the water. This practice has been suspended in some states in which olfshore regions are prospected because of state rulings requiring that such operations not interfere with fishing. It is obvious that drill hole tubing which extends above the surface of the water or above the ground level and below the surface of the water could interfere with operation of fishing nets. To overcome this difiiculty and to permit a large number of holes to be drilled in advance of j the explosive charge and removal of the drill tubing.

. One object of my invention is to provide a method for making a drill hole for placing an explosive charge whereinthe drill tubing is removed.

Another object of my invention is to provide a method for makingdrill holes for placing of explosive charges wherein the drill tubing is removed and yet a marker is left.

Still another object of my invention is to provide an i improved knock-01f and expendible drill bit, and adapter 7 assemblyfor use in such operations.

Yet another object of my invention isto provide an improved drill bit, and adapter for use in said operations wherein the drill bit iseasily separated from the adapter and tubing and the latter are recovered for reuse.

These and other objects and advantages of my inven: tion will be realized upon reading the following description, which taken with the. attached drawing, forms a part of specification.

In the drawing Figure is an elevational view of my 2 knock-off drill apparatus positioned in a drill hole heneath a body of water. Y

Figure 2 is an elevational view, partly in section, of the apparatus of Figure 1 after placement of an explosive charge. I

Figure 3 is an elevational view of a. portion of my apparatus. 1

Figure 4 is an elevational view of another portion of my apparatus.

Figure 5 is an elevational view, partly in section, of still another portion of my apparatus.

Figure 6 is an elevational view of still another portion of my apparatus.

Figure 7 is an elevational view, partly in section, of a portion of the apparatus of Figures 1 and 2 on an enlarged scale.

Figure 8 is a side elevational view, partly in section, of the apparatus of Figure 7.

Figure 9 is a plan view of a portion of the apparatus of Figures 7 and 8.

Figure 10 illustrates an alternate form of a portion of my invention. a

Referring now to the drawing, in Figures 7 and 8 reference numeral 11 identifies a collar or adapter which is provided with internal threads 35 for attaching to the lower end of a drill tubing 53 (Figs. 1 and 2). Such a drill tubing is identified by reference numeral 53 in Figures l and 2. The upper portion of this adapter 11 is identified by reference numeral 12 while the lower portion is identified by reference numeral 13. This lower portion 13 of the adapter is intended to telescope over an upper portion of a shank 15 of a drill bit 14. At the bottom of the drill bit are disposed a pair of oppositely directed cutting edges 16. The cutting edges 16 are so disposed on lower portion of the drill bit that when the tubing 53 and bit 14 are rotated by drivehead 51a in a clockwise direction the cutting edges advance into the earth. Drivehead 51a is powered by engine 5112 which is supported on barge 51c. In the lower portion of the drill bit 14 and near the cutting edges 16 area pair of open ings 34 so disposed that drilling fluid can be pumped downward through the drill tubing and drill bit and through the holes to cool the cutting edges and to assist in carrying away the cuttings. These openings 34 are so positioned that th'e'discharge of the drilling'fluid is on the back side of the cutting edges.

The drill bit 14 is provided with a shoulder 27 extending all the way around the bit. This shoulder serves as a seat for the lower end 28 of the adapterll. In order that the drill tubing which is threaded to the adapter can rotate the drill bit a plurality of keys or splines 26 are provided on the outer periphery of the upper portion 15 of the bit. These keys or splines are disposed with their longitudinal axes vertical. A plurality of keyways 25 are provided in the inner surface of the lower portion 13 of the adapter in such a mannerthat the keys or splines 26 match with the keyways 25. When the lower portion 13 of the adapter is positioned over the upper portion 15 of the drill bit with the keys and keyways matching the drill bit is rotated upon rotation of the adapter.

Inorder to prevent the drill bit 14 from becoming dis engaged from the adapter 11 as the drilling assembly is lowered from the drilling rig through the water to the surface of the ground beneath the water one or more shear pins 29 are provided. Holes are drilled at an angle of about 30 from the horizontal in the wall of the lower portion 13 of the adapter. Horizontal holes are drilled through the shank portion 15 of the drill bit in such a manner that the holes in the adapter match the holes in valve least two shear pins can be inserted through these openings to hold the drill bit to the adapter until such time -itgisqdesiredsto separate Lthese members. .In some cases it is preferable to provide four setssof' theseshearxpin '-holes*so.that four-'shear pins'can be used. I have found, thowever rthat in-gmost, applicationssthe useof two shear pins for holding the drill bit to the adapter are sufficient. 1 v As shear pins: I use ordinary-nails or sheet metal nails. When using sheet metal nails or any other type of nail, iit ispreferable that-the headsoflthe nails be made of lead so that upon insertion of the nails through the. holes the heads. can beflattenedagainst the outer surface of the adapter. In thismannerthe nail-.heads 'will. not be sheared oif nor abraded duringthe drilling operations. I prefer to construct the shearpin holes in the directions .d-isclosed above 7 so that upon driving a nail through .these -.openings. the. nailwill become bent and therefore will be held tightly in place.

Asmentioned hereinbefore one. preferred method of operation of such a drill bit.is to use a-inud .or:merely :water as adrilling-fluid; Whenusingagdrillingfluid in this operation the fluid is pumped downward. through the drill tubing into the drill-bit and outvopenings 34 to cool the cutting edges of the bit and to assist in removal of the cuttings. In order topreventcuttings or sands or other solid matter from flowing through openings 34 from the .bore hole into the drill: bit at such times that drilling operations are suspended I-providea check valve 17. This. check valve permitsdownward flowof fluid through the tubing but checks upward flow. In one embodiment this check valve'comprises a ring or plate 19 having an opening .31.centrally positioned therein. Immediately below. this plate is thevalve 21 of the assembly. In one .embodiment I preferto use leather as the valve. This valveis'circular in shapenand has a diameter about the .same as the outside diameter of the drill shank 15. This .valve has a. support ring 21a which rests upon an upper surface 24 of the shank, see Figure 7. A flapper 21b is movably attached, by neck 210 to support ring 21a. The flapper, neck. and ring are. usually made from one piece of material, as leather, by merely cutting out a section leaving slot 21d. .An opening 30 (Figs. 7 and 8) in the valve 17 is 'for passageof fluid downward when the .valve is open. Washers.20 and 22'are provided on .the upper and lower faces. respectivelyv of .valve 21. The diameter ofthe larger washerzz and the diameter of the opening.31 in plate 19 are related in such amanner that when upward pressure against the valve is greater than downward pressure thereon-the valve closes and the flapper 21b cannot be forced upwandthrough opening 31. A bolt 23 extends through washers 20and 22 and through the valve 21 to hold these three members together. A shoulder or flange Y 18 is provided around the inner periphery ofthe adapter 11 at a level intermediate the threaded section and valve 17 to prevent the valve assembly from moving upward. It is not necessarythat shoulder .18 .hold the valve assembly tightly against shoulder 24 but the valve should be maintained in close :proxirgrity to the shoulder 24 as illustrated in Figures 7 and v In Figure 8 thevalve- 17 is illustrated as beingin an open position while Figure 7 shows the valve closed.

Figure-9 is a plan'view illustrating valve 21. The valve comprises a ring 21a, a flapper 21b, neck 21c with a slot 21d permitting free movement of flapper 21b.

Figure is' a sectional view of a portion of a shank a ofa' drill bit similar to bit 14 of Figures 7 and 8, provided with a keyway 25a, and a portion of a collar or adapter 11a with a key or spline 26a matching the keyway 25a. e I f Inthe operation and use "of the apparatus of my invention; the drill .bit 14 is attached to the adapter. 11 with ne'ior more shear pins .29 af ter positioning the'check 17. The adapter 11 is then threaded onto the lower end of the drill tubing and the bit and drill. tubing are then lowered through the water preparatory to drilling. Any suitable above water drilling means can be used, such as drilling apparatus on a floating barge or on a more or less conventional boat. About the only require ments being that the power apparatus be adaptable for rotating the drill tubing and :bit and furthermore that the power apparatus, be maintained relatively still so as not to bend the tubing by horizontal movement of the barge or boat. After the drilling is started water is usually pumped into the top. of the drilltubing and, is forced through the check valve 17 and through openings 34 and this water with drill cuttings flows upward around the drill bit and adapter and out the top of the drill hole. Such operation is continued until the hole has been drilled to a desired depth. The drilling is then stopped and a go-devil 60 (Figure 6) is dropped down the tubing and upon impact against the check valve 17 shears'the shear pins29 to free the drill- 14.from-the adapter 11.; The drill bit 14 is'in some instances raised, upwardand away from the bottomof the drill hole and the go-devil is then dropped thereby shearing pins 29 and loosening the drill bit 14 from the collar or adapter 11. The plate 19 is usuallymade ,sufliciently thick that it can withstand the impact of the go-devil. This go-devil.60.is substantially a piece of iron 2% to 3.inches in diameter and from 3 to 4 feet in length and is of considerable weight. The godevil should be sufficiently heavy, that when it is dropped down thetubing it will strike the upper portion of the valve. or the upper surface 24. of the drill. bit with sufficient forceto shear the pinsvand loosen the bit. It is necessary; to retrieve the go-devil notonly for further use insubsequent operations but IOuIIIlOVE it from the tubing for placing ofthe explosive charge. In order to retrieve the go-devil an eye bolt 61 or;hook is attached to the top of the go-devilsand, cable is attached thereto in such a manner that the go-devil can be pulled up the tubing after it has served, its purpose. vAfter the go-devil has been removed from the tubing and of course the adapter 11 loosened from the drill bit, an explosive charge 56 (Figure 2) is then lowered through the tubing 53. A pairof .wires 55 are ,attachednto the charge for passage of electric current for detonation. The wires are, of sufficient length to'extend from the charge at the bottom of the borehole to a level well above the surface of the water 51. I use one of several methods for removing the drill tubing and adapter from the drill hole. One method involves attaching a floatsuch as a wooden float 59 (FiguresZ and 3) to the upper ends of wires 55, and then the tubing is pulled upward and over the float. As the lower end of the tubing 53 and the adapter. 11 are removed from the water the wooden float 59 floats on the water. This woodenfloat is then allowed to remain as a buoy or float to identify the locationof the bore hole withits explosive charge. The actual drill bit 14 is the only piece of apparatus which is notretrieved for further use. Sincethese drill bits are inexpensive their loss is a very small item. v

Another means for wi drawing the tubing 53 from the drill hole involves use of a hollow pipe .57 (Figure 4 closed, water-tight at both ends. Use of thishollow pipe in retrieving the drill tubing is similar to that disclosed relative to the wooden float 59. Ahook .or eyeSS isprovided at one end of pole 57 for attachment of the upper ends of wires 55. ,1

Reference numeral 52 identified the surface of the earth beneath the body of water. 1

I use still another method for marking of the drill hole after placement of the explosive charge. This latter method involves use of a steel band 54 bent generally into the form of a circle with theends being bolted together as illustrated in Figure 5. The circle so formed is tied to the upper endsof wires 55 after the explosive charge is placed and is forced into the top of the tubing 53. Upon removal "of the tubing 53 upward the 'band 54 slides through the tubing and as the lower end of the tubing 53 approaches the water level the band 54, is caught with a hook to retrieve the ends of the wires 55. After the band 54 is removed from the tubing the wires are disconnected from the band and a float such as the hollow pole 57 or wooden float 59 is attached to the wires for permanent marking.

As many drill holes as desired can be produced in a manner herein disclosed with each drill hole being marked by a float. When using such floats as float 57 or float 59 fishing nets are easily operated and there is no danger whatever of obstructing movement of the nets. As soon as the net passes over a given float the float will merely rise to the surface of the water again.

I prefer to use a 4 inch drill tubing so that an. explosive charge package having a relatively large diameter can be used. When using an explosive charge of relative large diameter the entire charge is concentrated more nearly at a point. A charge so shaped is more efficient for geophysical exploration than is a long charge of small diameter such as would have to be used if the drill tubing were smaller than 4 inch tubing.

By increasing the length of tubing 53 the drill hole can be drilled to any desired depth under water. In general the deeper the drill hole is made the smaller the explosive charge can be and yet carry out eflicient geophysical exploration.

While I have described the shear pin holes in the lower portion 13 of the adapter 11 as being drilled at an angle of about 30 from the horizontal this angle is not critical and it can be sloping at angles more or less than 30 as desired, but the hole should be sloping to a sufiicient degree that a nail driven therethrough through and through a corresponding horizontal opening in the drill shank will be bent and therefore held rigidly in place.

From the above description it is seen that an improved knock-off bit, and adapter assembly have been devised which permit drilling of, for example, a hole With a 4-inch diameter drill tubing for use of concentrated explosive charges. Furthermore the drill bit is rigidly held by a plurality of keyways and shear pins to a collar or adapter on the lower end of the drill tubing. My invention provides an improved means of planting explosive charges under the floor of bodies of water without requiring that the drill pipe be left in place between the time that the drill hole is made and explosive charge is set off. Even when drill pipes are allowed to remain in the holes after placing the charges they are removed after the charges are detonated and all observations are terminated. The invention further illustrates methods for getting the wires to the charge through the drill pipe to permit removal of the pipe without interfering with the wires. Other diameter drills and drill pipes can be used when desired. The 4-inch drill and tubing were described merely as a preferred example when drilling holes for explosive charges in geophysical exploration operations.

One alteration suitable for use with the apparatus of my invention is that a key can be made integral with the inner surface of the lower portion 13 of the collar or adapter 11 and the matching keyway formed in the outer surface of the drill shank 15 in place of the key on the drill shank and keyway in the collar as described hereinbefore.

While certain embodiments of the invention have been described for illustrative purposes the invention obviously is not limited thereto.

I claim:

1. Apparatus for preparing a cavity for an explosive charge in the earth below a body of water comprising, in combination, a drill bit adapted upon rotation to bore a hole into the earth, a drill tubing for rotating said bit, means for rotating said tubing, means for transmitting rotation from said tubing to said drill bit comprising a collar on the lower end of said tubing, the lower portion of said collar surrounding the upper portion of said drill bit, at least one key disposed axially on one of the outer periphery of said upper portion of said drill bit and the inner periphery of said lower portion of said collar, and a matching keyway on one of the inner periphery of said lower portion of said collar and of the outer periphery of said upper portion of said drill bit respectively, and means for holding said upper portion of said bit Within said lower portion of said collar, this latter means comprising at least one shear pin extending through the walls of said upper portion of said bit and the lower portion of said collar, a check valve assembly supported by the up per end of said upper portion of the drill bit, a flange on the inner surface of said collar above and adjacent said check valve assembly holding same against upward movement and the valve of said assembly being positioned to open in a downward direction for downward circulation of fluid through said tubing, bit and check valve assembly.

2. A knock-off bit and adapter assembly comprising, in combination, an adapter of circular cross section, means to attach the upper portion of said adapter to a drill tubing, a drill bit adapted upon rotation to bore a hole into the earth, the upper portion of said drill bit being disposed within the lower portion of said adapter, at least one key disposed axially on one of the outer periphery of said upper portion of said drill bit and the inner periphery of said lower portion of said adapter, and a matching keyway on one of the inner periphery of said lower portion of said adapter and of the outer periphery of said upper portion of said drill bit respectively, means for holding said upper portion of said bit within said lower portion of said adapter, said latter means comprising at least one shear pin extending through the walls of said upper portion of said bit and the lower portion of said adapter, a flange disposed around the inner Wall of said adapter intermediate its upper portion and its lower portion, and a check valve assembly supported by the upper portion of said drill bit and held against. upward longi tudinal movement by said flange, and the check valve of said assembly being positioned to open in a downward direction for downward circulation of fluid.

References Cited in the file of this patent UNITED STATES PATENTS 1,512,066 Taylor Oct. 21, 1924 1,905,497 Peters Apr. 25, 1933 2,532,686 Ware Dec. 5, 1950 2,550,563 Hughes Apr. 24, 1951 2,562,298 Creighton July 31, 1951 2,614,804 Carlisle Oct. 21, 1952 2,621,895 Toelke Dec. 16, 1952 2,665,886 Ellis Jan. 12, 1954 2,669,431 Crowell Feb. 16, 1954 2,685,251 Davis et al. Aug. 3, 1954 2,773,669 Norman et a1 Dec. 11, 1956 2,793,833 Daniel May 28, 1957