US 2513398 A
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Description (OCR text may contain errors)
July 4, 1950 BENKE 2,513,398
CORE CUTTING DEVICE Filed May 18, 1945 Haas; v Inventor 14in! ornez/ Patented July 4, 1950 UNITED STATES PATENT OFFICE CORE-CUTTING DEVICE Roy Benke, Dallas, Tex., assignor to The Atlantic Refining Company, Philadelphia, Pa., a corporation of Pennsylvania Application May 18, 1945, Serial No. 594,411
The present invention relates to improvements in devices used for the purpose of cuttingfgeologic samples from the side wall of a bore hole.
During the drilling of. awell the drill operator is always vitally interested in the type of geological strata through ;which the hole must pass since an accurate knowledge of the subsurface formation is highly conducive to increased efficiency in operation. In a vicinity where a plurality-of holes have been drilled, a picture of the formation underlying the entire locality may be obtained by correlating the information gleaned from the samples taken fromeach well.
The most practical and efiicient .method of obtaining the samples which will disclose the desired information is to cut av core from the rock strata. In order that the sample shall give a true picture of the formation it must be so out that its integral portions will'remainintheir true relative position with each other. Also, such core cutting device must be of relatively few parts and adapted for operation in the mud and water of a bore hole when positioned at a predetermined depth therein.
Therefore, one of the objects of this invention is to provide a means for obtaining a true ample of the geologic formation through which bore hole has passed.
Anotherobject of the'invention is to provide a means operable from-the surface of the earth for cutting a, sample from the side of abore hole at any predetermined depth Within the hole.
A further'object of the invention is to provide a means for cutting a core which is peculiarly adapted for operation in the mud and .water normally containedin abore hole.
Other objects .of the invention will be apparent from the description and claims which follow.
Reference is now made to the drawing, wherein like numerals are used to designate like parts.
Figure 1 is a side view partially in cross section, showing one form of the invention.
Figure 2 is a side View partially in cross section showing a modified form of the device depicted in Figure 1.
The device shown in Figure 1 comprises a cylindrical casing I provided with an opening 2 in one side wall thereof. An eye 3 is attached to the upper end of casing I and is adapted for attachment to a cable for lowering or raising the casing I within the confines of the well bore. A partition 4 divides the casing I into an upper and a lower compartment.
The lower compartment contains an operating arm Bafiixed to pivot 6 at the upper end of opening 2 in casing I. Such construction permits the operating arm to swing through opening 2 in casing I. The pivot and operating arm are of sufficiently sturdy construction to prevent any deviation from the plane of the are through which said arm is adapted to swing.
A leaf spring 1 is aflixed to a bracket 8 extending transversely across the-casing i, such bracket being rigidly attached to the casing wall by welding or other means. When operating arm 5 is in a retracted position within casing 5, leaf spring 7 is held compressed by said operating arm and applies continuous pressure to the arm to urge it outwardly of the casing. A core bit barrel housing 9 is aiiixed to the free or lower end of operating arm 5, and contains therein a core bit barrel Iii which, during the operation of the device, is rotated as hereinafter described and cuts therequired sample from the side of the bore hole.
Within the upper compartment are positioned two motors II and I2 immovably held in place by brackets l3 and M affixed to the walls of easing I, the function of which motors will be described hereinafter. Power is supplied to motors II and I2 by-pairs'of conductors 32 and 33, respectively, of an electric cable I5 introduced through the wall of easing l and insulated from said wall by means of insulator it.
The drive shaft ll of motor ll passes through bearing I 8 in partition 4 and is connectedto flexible drive shaft Ill, which, in turn, is operably connected to core bit barre-l it by means of cooperating gears 34 and 35 attached respectively togdrive shaft l9 and core bit barrel Ill, as shown. A cable 20'is afiixed to reel i-ZI actuated by motor I2. The cable 2d passes through an aperture in partition 4, then through pulley 23 affixed to the wall of casing I, through pulley 24, and is connected to core bit barrel housing 9 at lug 25. A light tension spring 26 is connected at one end to pulley 24 and at the other end to a lug 21 on the wall of easing I.
In Figure 2, a variation of the spring member depicted in Figure 1 is shown. Leaf spring I has been omitted and, in its stead, a coil spring 28 is used. To stabilize the coil spring 28 so that it will not buckle nor double under pressure, a telescopic guide bar 29 is provided axially of the coil spring 28 and is pivotally afiixed to the wall of casing I at 30 and the operating arm 5 at 3|.
In the operation of the device shown in Figure 1, the casing I is lowered into the bore hole and 3 positioned at a predetermined depth, the operating arm 5 being held retracted within the casing by means of cable 20 drawn taut by reel 2|. When casing l is positioned at the proper level current is supplied to motor I2 through electric cable [5, thereby actuating reel 2| and paying out cable 20. As cable 20 is slackened, operating arm 5, urged by the continuous pressure of leaf spring 1 wings through opening 2 in casing I until core bit barrel It] makes contact with the side wall of the bore hole. several further revolutions to insure that cable 20 will be s-ufliciently slack to permit operating 'arm 5 to be extended further through opening 2 during the actual coring process. Any excess slack in cable 20 by reason of the bore hole being of a smaller diameter than estimated, is fully taken up by the action of light tension spring 26 acting through pulley 24. It will be apparent that the tension on spring 26, While being sumcient to take up the slack of cable 20, is less than I that of leaf spring 1. Otherwise, operating arm 5 could not be projected through opening 2 as required.
At this point, the current supplied to motor I 2 is cut off and the motor stopped. Current is then supplied through cable 15 to motor H which actuates core bit barrel I through flexible drive shaft l9. As the core bit barrel I9 revolves and cuts the core, the barrel is forced into the forma- 1 tion by pressure of leaf spring 1 exerted again-st operating arm 5. 1 cutting the supply of current to motor II i cut Upon completion of the core on". To insure that the core will remain within the barrel when operating arm is withdrawn, casing i may be slightly raised or lowered in order to break off the core at itsbase.
Motor I2 is started in reverse by reversing the current supplied thereto through cable l5. Reel 2!, actuated by motor l2 Winds up cable 29, thereby withdrawing operating arm 5 into the Motor I2 is permitted casing 1 against the pressure of leaf spring I.
Such operation is continued until the arm is fully retracted. At that point, the current supplied to the motor 12 is cut off, the device raised to the surface, and the core extracted therefrom.
'In the modification of the device as shown in Figure2, the function of coil spring 28 in applying continuous pressure to operating arm 5 is identical with the function of leaf spring 1, as described above.
1. A device for obtaining geologic samples from the side wall of a bore hole, comprising a, casing having an opening in a side wall thereof, an
operating arm pivotally mounted on the casing adjacent said opening and limitedly extendable from said casing through said opening, a
core bit barrel housing afl'ixed to the free end of said operating arm, a core bit barrel rotatably mounted within said housing, means for rotating the core bit barrel, spring means disposed within the casing applying continuous pressure to the operating arm urging it outwardly of the casing, and means operable tov withdraw the operating arm inwardly of the casing againstthe pressure of the spring means.
2. A device for obtaining geologic samples from the side wall of a bore hole, comprising a casing having an opening in a side wall thereof, an operating arm pivotally mounted on said casing at the upper end of said opening and limitedly extendable from said casing through said opening, a core bit barrel housing afliXed to the free end of said operating arm at a right angle thereto, a core bit barrel rotatably mounted within said housing, means for rotating said core bit barrel, spring means disposed within the casing applying continuous pressure to the operating arm urging it outwardly of the casing, guide means for stabilizing said spring means, and means operable to withdraw the operating arm inwardly of the casing against the pressure of the spring means.
3. A device for obtaining geologic samples from the sidewall of a bore hole, comprising a casing having an opening in a-sidewall thereof, an operating arm pivotally mounted on the casing ad- J'acent said opening and limitedly extendable from said casing through said opening, a core bit barrel rotatably mounted on the free end of said operating arm, means for rotating the core bit barrel, spring means disposed within the casing applying continuous pressure to the operating arm urging it outwardly of the casing, and means operable to withdraw the operating arm inwardly of the casing against the pressure of the spring means.
REFERENCES orrn The following references are of record in the file of this patent:
Bandy ..Jan. 1, 1946