US2883154A - Method of positioning charges and removing drill stems from shot holes - Google Patents

Description

April 21, 1959 1. P. DANIEL, SR

METHOD' CF' POSITIONING CHARGES AND REMOVING DRILL sTEMs FROM SHOT HOLES Filed Nov. so', 195e 2 Sheets-Sheet 1 Plll 21, 1959 J. P. DANIEL., SR 2,883,154

METHOD OF' POSITIONING CHARGES AND REMOVING DRILL STEMS FROM SHOT HOLES y j Filed Nov. 30,- 1956 2 Sheets-Sheet 2l 1NVENToR- 'United States. Patent O METHOD OF POSITIONING CHARGES AND RE- MOVING DRILL STEMS FROM SHOT HOLES John P. Daniel, Sr., New Orleans, La.

Application November 30, 1956, Serial No. 625,466

3 Claims. (Cl. Z55-1.8)

This invention relates in general to new and useful improvements in the drilling of shot holes for seismographic operations, and more specifically to an improved method of placing charges in shot holes after a drilling operation while the drilling tool is still in the shot hole and the removal of such drilling tool over the `detonator wire for the charge. v #This application is a continuation-in-part of my copending application Serial No. 337,835, tiled February `19, 1953, and now Patent No. 2,793,833, lgranted May 28, 1957.

` In seismographic operations, it is necessary that a large number of explosive charges be exploded beneath the .ground simultaneously. In order toaccomplish this, itis necessary that for each explosive charge a shot hole be drilled.` Unfortunately, in seismographic operations for oil fields the formation of the earth in which the shot holes -are being drilled is such that if the drilling tool were removed from the shot hole prior to the placing of the explosive charge therein, the walls of the shot hole would collapse and prevent the proper positioning ofthe explosive charge. It has therefore been necessary to place the explosive charge within the shot hole while the drilling tool remains therein and to explode such explosive charge while the drilling tool remains in the shot hole with the resultI that the drill bit and a lower portion of the drill string of the drilling tool are destroyed.

Not yonly has the heretobefore method of drilling shot holes, ythe placement of explosive charges therein and the tiring ofexplosive charges been expensive because of the destroying of material, particularly when such material must be transported to out-of-the-way places, but also extra work has beeninvolved. It is necessary that one crew drill the shot holes and place the explosive charges. The next crew then comes along and lires the explosive charges and records the results thereof. In view of the fact that many state laws require that the drill string be removed from the shot hole and also to salvage the undestroyed portion of the drill string, it is necessary that either a third crew or the rst crew must pull the drill Vstrings after the explosive charges have been red.

It is therefore the primary object of this invention to provide an improved method of drilling shot holes and placing explosive charges therein which may be accomplished with one setup and with the loss of a minimum amount or in some instances none of the drilling equipment.

Another object of this invention is to provide an improved method of anchoring a detonator Wire for an explosive charge in such a manner whereby a drilling tool may be pulled from a shot hole after the explosive charge hasbeen placed therein and over the detonator wire thereof without the detonator wire being any problem whatsoever during the removal operation.

These, together with vother objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafterdescribed :and claimed, reference being had to the Ice 2,883,154

lowered into the shot hole through the drilling tool,.

intermediate portions of the drilling tool and the earth being omitted;

Figure 2 is an enlarged sectional view showing the drilling tool elevated slightly from the bottom of a shot hole during the withdrawal operation of the drilling tool, the balled upper end of the detonator wire being shown in its frictional engagement with the drilling tool;

Figure 3 is an enlarged sectional view similar to Figure 2 and shows the nal stage of the withdrawal of the drilling tool with the explosive charge remaining in the bottom of the shot hole; and

Figure 4 is an enlarged exploded perspective view of the drill bit of the drilling tool with portions thereof being broken away in order to clearly illustrate the internal construction of the drill bit.

Referring now to the drawings in detail, it will be seen that there is illustrated in Figure 4 a special drill bit which is referred to in general by thereference numeral 10. Thedrill bit 10 includes 'amain drill section 12 and anauxiliary drill section 14. Also, if desired, thedrill bit 10 may include a valve 16.

Themain drill section 12 includes an uppercylindrical portion 18 which has depending therefrom a pair ofintegral teeth 20. Theteeth 20 project outwardly beyond thecylindrical portion 18 and are in diametrically spaced relation. It is to be noted that theteeth 20 are longitudinally curved so thatcutting tips 22 thereof are offset and are disposed at an angle to the longitudinal axisof the dri-l1 bit to effect a cutting operation.

In order that sections `of a tubing of la drill suing may be attached to thedrill bit 10, themain drill section 12 is provided in theupper portion 18 thereof withinternal threads 24. Thethreads 24 will be scattered for the particular type of tubing with which thedrill bit 10 is to be used.

Extending through themain drill section 12 is abore 26 which will be considered a flow passage. A lower part of thebore 26 is enlarged and there is formed in the interior of the main drill section 12 a downwardly facingshoulder 28. The purpose of thisshoulder 28 will be set forth in detail hereinafter.

Formed in the inner faces of theindividual teeth 20 areguideways 30. Theguideways 30 extend longitudinally of themain drill section 12 and are in opposed diametrically spaced relation. The purpose of theguideways 30 will be set forth in detail hereinafter.

Theauxiliary drill section 14 includes abody portion 32 which is generally cylindrical in outline. Formed integrally with thebody portion 32 and extending downwardly therefrom areteeth 34. Theteeth 34 are disposed closely adjacent to each other and are longitudinally curved so as to presentcutting edges 36 which are disposed at slight angles to the longitudinal axis of theauxiliary drill section 14. It is to be noted that theteeth 34 are curved in the same manner as theteeth 20 so that theteeth 34 cooperate with theteeth 20 in a. drilling operation.

Thebody portion 32 is provided with an enlargedopening 38 therethrough which functions as a ilow passage. The opening 38 communicates through the bottom of theauxiliary drill section 14 by means of abore 40. Thus drilling fluid may pass through theauxiliary drill section 14. A

In order that theauxiliary drill section 14 may be Patented Apr;A 21 ,Y 1959 positioned 'within the lower part of themain drill section 12 and to facilitate the turning of theauxiliary drill section 14 with themain drill section 12, there is formed on the exterior of the body 'portion 32 longitudinally extendingribs 42. Theribs 42 are in diametrically spaced relation and are of a size and configuration to be received within theguideways 30. Normally the pressure exertedupon the drill bit during the drilling operation twill 4be-fsufcient'to retain the auxiliary drill section 14 :withn themain drill section 12. However, if desired, suitable frangible locking means may be used to prevent the'two from separation accidentally.

When thedrill bit 10 is assembled, the valve 16 is disposed above the -auxiliarydrill section 14 and is retained in 'engagement with the shoulder '28 thereby. The valve 16v includes astiffening plate 44 which has secured to the llower'portion thereof asealing plate 46. Thesealing plate 46 has acentral flapper portion 48 which is hingedly connected to the remainder thereof to facilitate the 'flow of drilling mud or other drilling 'lluids through the valve 16and at the same time prevent the reverse ow thereof.

At this time it is pointed -out that in the drilling of shot holes in kmost instances theauxiliary drill section 14 will be required. However, in certain soils, parti'cularly swampy `ground and the like, it is not necessary that there be provided the auxiliary drill vsection i114. When Vthe ground in which the shot -hole lis being drilled is ysulliciently soft, the core which would normally be forme'd'fby thecutting action of themain drill section 12 will be washed away by the drilling fluid and the necessity of the central portion of the drill which theauxiliary drill section 14 represents is eliminated. However, at such time as theauxiliary drill section 14 is required, after the drilling operation is completed, it will be removed from themain drill section 12 prior to the lowering Iof an explosive charge into the shot hole which has been -drilled in accordance with the procedure set forth in 'my copending application Serial No. 337,835. 'Ihe valve 16 will be removed at the same time.

Referring now to Figure l in particular, it will be seen that there has been drilled in the earth 50 a shot hole 552 of fa desired depth. Theshot hole 52 has been diill'ed'lby utilizing a drilling tool which will be referred to 1in Igeneral by thereference numeral 54. The drilling tool -52'4 lincludes adrill string 56 and thedrill bit 10, only the uppermain section 12 of thedrill bit 10 being used. Thedrill string 56 includes a plurality of individual sections ofdrilltubing 58 which are suitably coupled/to each other and to thedrill bit 10. It is to -be understood that the terrain in which the shot hole "52 has `been drilled is relatively soft and that it has been found that theauxiliary drill section 14 may be eliminated Jduringfthe drilling operation.

`-`With theVdrilling tool 54 remaining in theshot hole 52 to prevent the caving in of the earth formation, an explosive 'charge 60 has been lowered into theshot hole 52 down through thedrilling tool 54 utilizing a detonator wire^62 which is secured to the explosive charge 60l for the purpose of exploding it at a later time. It is to Tbe' understood that theexplosive charge 60 will fall readilythrough the entire drilling tool 54' due to the provision of theflow passage 26 in the main drill section 12 'andthe `normal tubular 'construction of the drill string 5'6.

WhenA'the detonator wire 62 is connected to theexplosive charge 60, it is normally dispensed from a reel. Thus thereis provided any desired amount of thedetonator wire 62. Accordingly, in accordance with the practice of `this invention, 'an extra amount of thedetonator wire 62 is cut off 'from the reel and this extra amount oft'heidet'onator wire62 is formed into aball 64 which is forced into the upper part of thedrill string 56. It is to be understood that theball 62 is of a size to frictionally engage the interior surface ofthe individual sections of .4tubing 58 and that the friction between theball 64 and the drill .string 56 is such that theexplosive charge 60 will remain at the bottom Vof theshot hole 52 even though thedrilling tool 54 is removed therefrom.

In order that thedrilling tool 54 may be pulled from theshot hole 52, there is provided a liftinghead 66 which is connected by acable 68 to the draw Works (not shown) of the drilling rig (not shown) used in drilling theshot hole 52.

Referring `now to Figure 2 in particular, it will be seen that thedrilling tool 54 has been moved slightly upwardly in the shot 'hole 52 in the process of being pulled from theshot hole 52. At this time thedrill bit 10 has moved from above theexplosive charge 60 which remains at the bottom of theshot hole 52. At the same time, the -ball 64 of thedetonator wire 62 remains at its same position above the level of the ground Si) as the sections oftubing 58 pass up over theball 64.

The individual sections oftubing 58 are removed during the pulling ofVthe drilling tool 54 in the normal manner. The pulling of thedrilling tool 54 is continued in the customary manner until such time as the last section oftubing 58 and thedrill bit 10 are disposed above the level of the ground 50', as is best illustrated in Figure 3. Before the 'ball 64 of thedetonator Wire 62 passes out yof thedrill bit 10, one may reach his hand beneath ythe drill `bit l10 and grasp thedetonator wire 62. Thus, the upper end of thedetonator wire 62 may be readily anchored above the surface of the ground S0.

It is pointed out atv this ktime that while the walls of theshot hole 52 have been shown as being undisturbed after the pulling of thedrilling tool 54, in most instances this is not the case. Particularly in soft formations the walls of theshot hole 52 will cave in and theexplosive charge 60 will be buried. This is desirable rather than detrimental inasmuch as theexplosive charge 60 will be'more eie'ctive in a seismographic operation if it Vis covered and not permitted to blow back through the -shot hole 52.

It is 'to be understood vthat a plurality of shot holes S2 will y'he drilled and theexplosive charges 60 placed therein by a drilling crew. This drilling crew will anchor the upper ends of thedetonator Wires 62 in .a suitalble manner above the surface of theground 50. 4Then the detonator and recording crew will follow. This second crew will connect a suitable ring device (not shown) to the upper ends of thedetonator wires 62 so that a large number of theexplosive charges 60 may be exploded simultaneously.

It is to be understood that when theauxiliary drill section 14 is utilized in conjunction with themain drill section 12, the only difference in the procedure set forth above willvbe that theentire drilling tool 54 will be slightly elevated above the bottom of theshot hole 52 and the valve 16 and theauxiliary drill section 14 will be removed prior to the lowering of theexplosive charge 60 down through thedrilling tool 54. Also, the valve 16 and theauxiliary drill section 14 will not be retrieved.

From the foregoing description of thedrill bit 10 and the use thereof in the yformation of shot holes, yit will be readily apparent that a great saving will be effected. Not only is all of 'thedrill string 56 and themain section 12 of thedrill bit 10 retrieved, which in the case of drilling in soft formations constitutes the entire drilling .tool 54, ibut the entire drilling and pulling operation maybe accomplished `by a single crew in a single setup. This fin itself is a large cost factor. Further, in certain terrains it is extremely difficult to move in the drilling equipment and special transportation devices are required. Inasmuch as `there is no loss of thetubing 58, it will be seen that only thattubing 58 which is required during the actual drilling operation with a few spare sections, will be required "to Vbe moved into inaccessible areas. This provides a further saving. While with anindividual shot hole 52 such a saving may not appear too great, it is to be understood that shot holes 52 are used for only one explosion and that hundreds of shot holes are drilled in a seismographic operation. Therefore, in View of the fact thatmany shot holes 52 are formed, it will be seen that the saving eifected by the use of the drill bit and the method of placing theexplosive charge 60 and the removal of thedrilling tool 54 prior to the explosion of theexplosive charge 60 will be relatively great.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In the drilling of shot holes with a drilling tool including a hollow drill string having a bit secured thereto, the bit having a flow passage communicating with the drill string to provide for circulation of drilling lluid through the drill string and bit, the method of charging a shot hole while the drilling tool remains in the shot hole comprising providing an explosive charge with an elongated length of detonator wire, lowering said explosive charge into the drilling tool through the ow passage and into the shot hole using said detonator wire, forming the upper end of said detonator wire into a large ball of a size to pass through the drilling tool and frictionally engage the interior of the drill string, releasing said detonator wire, pulling the drilling tool from the shot hole over said detonator wire.

2. The method `of drilling and charging a shot hole comprising providing a drilling `tool including a drill string and a drill bit on the lower end of said drill string, said drill bit having a flow passage therethrough of a size substantially equal to the internal cross section of said drill string for the circulation of drilling fluid through 40 said drill string and with said drilling tool, providing an explosive charge with an elongated length of detonator Wire, lowering said explosive charge into said drilling tool through said flow passage and into said shot hole using said detonator wire, forming the upper end of said detonator wire into a large ball of a size to pass through said drilling tool and frictionally engage the interior of said drill string, releasing said detonator wire, and pulling said drilling tool from said shot hole over said detonator w1re.

3. In the drilling of shot holes with a drilling tool including a hollow drill string having a bit secured thereto, the bit having a flow passage communicating with the drill string to provide for circulation of drilling fluid through the drill string and bit, the method of charging a shot hole while the drilling tool remains in the shot hole comprising lifting the drilling tool a slight distance above the bottom of the shot hole, removing a portion of the drilling tool to increase the cross-sectional area of the flow passage to permit the passage of au explosive charge through the drilling to a point therebelow, providing an explosive charge with an elongated length of detonator wire, lowering said explosive charge into the drilling tool through the flow passage and into the shot hole beneath the drilling tool using the detonator wire, forming the upper end of the detonator wire into a large ball of a size to pass through the drilling tool and frictionally engage the interior of the drill string, releasing the detonator wire, and pulling the drilling tool from the shot hole over the detonator wire with the explosive charge remaining at the bottom of the shot hole.

References Cited in the le of this patent UNITED STATES PATENTS 1,905,497 Peters Apr. 25, 1933 2,282,596 Wise et al. May 12, 1942 2,464,781 Baker Mar. 22, 1949 2,793,833 Daniel May 28, 1957

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