US3342130A - Explosive holder for seismic prospecting - Google Patents

Description

Sept 19, 1967 T. E. MILLER ETAL EXPLOSIVE HOLDER FOR SEISMIC PROSPECTING 2 Sheets-Sheet l Filed March 8, 1966 sept. 19, 1967 EXPLOS IVE Filed March 8, 1966 MQW/@W vavN//w//s Fig.8

T. E. MILLER ETAL. 3,342,130

HLDER FOR SEISMIC PROSPECTING 2 sheets-sheet'z Fig. 7

. 7. Thomas E. Miller William A. Parker INVENTORS United States Patent 3,342,130 EXPLOSIVE HOLDER FOR SEISMIC PROSPECTING Thomas E. Miller, El Centro, Calif. (731 Poplar, Wasco,

Calif. 93280), and William A. Parker, El Centro,

Calif. (2109 1st St., P.O. Box 296, Wasco, Calif.

Filed Mar. 8, 1966, Ser. No. 532,727 7 Claims. (Cl. 102-21.8)

ABSTRACT OF THE DISCLOSURE A holder adapted to position an explosive charge within a borehole which holder comprises a tubular body member adapted to support the explosive `charge by the provision of upwardly and downwardly projecting resilient borehole wall gripping members adapted to normally preclude upward or downward movement of the holder subsequent to its being set at a predetermined position in the borehole.

The present invention relates to explosive holders and more specifically to explosive holders adapted to selectively secure a suitable charge of explosive at a predetermined point within a borehole such as is normally utilized in conjunction with a seismic prospecting procedure. More particularly, the present invention relates to an explosive holder of the class described which is adapted to secure an explosive charge within a borehole in such a manner so as to resist movement of the charge by an explosion or implosion caused by the detonation of another charge of explosive within the borehole.

Numerous devices have been proposed heretofore to facilitate placement of an explosive charge within a borehole. However, many such devices are unduly cumbersome, complicated and do not properly anchor the explosive charge so as to substantially resist movement of the charge due to the forces exerted by the detonation of another explosive charge within the borehole.

It is therefore a primary object of the present invention to provide an explosive charge holder adapted to selectively position an explosive charge within a borehole such as utilized in a seismic prospecting procedure.

Another object of the present invention is to provide an explosive charge holder adapted to selectively position an explosive charge within a borehole, which 'holder is provided with means engaging the borehole wall to preclude displacement of the explosive charge holder due to the forces exerted by the detonation of a second explosive charge within the borehole.

A further object of the present invention is to provide an explosive charge holder for seismic prospecting and the like which is adapted to be utilized in conjunction with explosive charges such as stick dynamite, as well as explosive lled containers such as metal cans wherein a plurality of cans may be threadably coupled to vary the charge.

Still another object of the present invention is to provide an explosive charge holder which comprises a generally cup-shaped body member provided with a plurality of rigidly secured spring steel members adapted to engage the'borehole wall in a manner so as to preclude displacement ofthe charge holder from its predetermined position within the borehole.

Still a further object of the invention is to provide an explosive charge holder of the class described wherein the borehole wall engaging means utilized to secure the charge holder is further provided with a restraining means to selectively prevent engagement of one or more of the borehole wall engaging means with the borehole wall so as to facilitate placement of the exploisve charge at a ICC predetermined point within the borehole after which the restrained borehole wall engaging means may be released from above ground to permit the borehole wall engaging means to grip the borehole wall.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a side elevational view showing one ernbodiment of an explosive charge holder constructed in accordance with the present invention positioned at the bottom of as well as at an intermediate point within a seismic prospecting borehole;

FIGURE 2 is an enlarged side elevational view of the charge holding device of FIGURE 1 further showing the method and means of selectively restraining certain of the elements `comprising the anchoring means so as to permit placement of the charge holder within the borehole;

FIGURE 3 is a perspective view of the explosive charge holder of FIGURE 2;

FIGURE 4 is an enlarged horizontal sectional view of the charge holder of FIGURE 1 taken substantially along the plane of line 4 4 of FIGURE l;

FIGURE 5 is an enlarged fragmentary side elevational View taken substantially along the plane of line 5 5 of FIGURE 2 showing details of the manner in which a plurality of explosive lled containers are secured to the body `rof the charge holding device;

FIGURE 6 is a fragmentary side elevational View of a further embodiment of an explosive charge holder constructed in accordance with the present invention which holder is primarily adapted to be utilized in conjunction with stick dynamite and the like;

FIGURE 7 is a side elevational view of the explosive charge holder of FIGURE 6; and

FIGURE 8 is a top plan view of the explosive charge holder of FIGURE 7.

Referring now to the drawings in detail and FIGURES 1 through 5 in particular, it will be seen that the embodiment of the present invention illustrated therein cornprises an explosive charge holder indicated generally at 10 which is positioned within a borehole 11 in engagement with the borehole wall 13. The holder 10 includes a generally cup-shaped body member 12 having a generally tubular vertically disposed side wall portion 14 and a horizontally disposed bottom wall portion 16.

As see-r1 best in FIGURE 5, the bottom wall portion 16 is provided with a centrally disposed aperture as indicated at 18 to facilitate securing a plurality of explosive lled containers such as 20 adapted to be threadably connected in contiguous longitudinally extending relationship. As also seen best in FIGURE 5, each of the explosive lled containers 20 is provided with a threaded male portion 22 at one end of the container and a threaded female connection as indicated, at 24 at the opposite end of the container, the inner diameter of which is complementary to the outer diameter of the threaded male connection 22. Thus, as seen in FIGURE 5 a plurality of explosive lled containers 20 may be secured to the body member 12 of the explosive charge holder 10 by inserting the male connection 22 of a container 20 upwardly through the aperture 18 in the bottom wall portion 16 of the body member 12 and then threadably tightening a second container 20 of explosive onto the above-mentioned container 20 by engaging the threaded female connector 24 with the male connector 22 projecting upwardly through the aperture 18. In a similar fashion the desired number of explosive holding containers may be secured in rupwardly and down-` wardly extendingr relationship to the first' two containers f 20 secured to the body member 12.

As further seen in FIGlURE 2y the` charge comprised of a plurality of'interconnected explosive filled containersy n above ground.

It will be further noted that the explosive charge holder 10 includes a stabilizing means indicated generally at 3f) which includes a plurality of arcuate yrelatively rigid resilient gripping members 32 which kare secured such as at 34 to the body member 12 intermediate of the ends thereof by means' of welding for example so as to provide a f plurality of outwardly diverging fingers adapted tor engage the wall 13 oftheborehole 11. The arcuaterelaktively rigidy resilient 'members 32 are prefer'ably,falthough notnecessarily, formedof spring steel for example.y And with` an upwardly, longitudinally extending explosive charge positioning means which includes a rigid `rod or n tube 140 rigidly secured to the body member 112 by means of welding or the like. The rod 140 is further provided with one or more spring clips 142 which pass` about the rod 140 and a stick of dynamite 120,y as seenk best in ,FIGURE 6, thereby frictionally retaining the dynamite 120 to they rod 140 The fuses 144 of the dynamite 120 are connected in a suitable manner to a squib device,

not shown, in order to facilitate' detonation of the ex' plosive. Although not shown, it will kbe understood that the relatively rigid arcuate resilient gripping members -132 maybe restrained in an inwardly disposed position by a restraining means analogous to the means 40 illustrated in connection with the embodiment of the invention kShown in FIGURE 2.

as seen best iny FIGURE 4, the ends of the members 32 are cut at 'a diagonal so asto provide sharp points such asat 33 to facilitatepenetration of the borehole wall 13 to aid in precluding movement ofthe positioned charge.

` y practice of thek presentinventionis thought to be obviousy Referring now 'to FIGURE 2, it will be seen that the lectively f releasable restraining means indicated generally at which is adapted to restrain two'or more of .ther outwardlydivergingends ofthearcuate members 32y inwardly out of engagement with the wall 13. Towards this end, several plies of a .plastic'orv 'cloth'adhesive tape 42r y y v members 132 are taped together such as with tape 42 tok n restrain the points 33 so'as to prevent their engagementr are wrapped about the outer ends of the members 32 to form a continuous loop thereabout, as seen in FIGURE 2. The tape is preferably notched as 'at 44 to facilitate severingthereof and the restraining means 40 is further proexplosivecharge holder 10k may kbe provided with a sef Itwill be further understoodthat the clips k142 may alternately be rigidly secured to the rod 140 at appro-y priate `points kalong the lengthy thereofy ydepending uponv the length of the stickexplosive utilized. n n n n Although the method of utilizing the explosive charge holders 1.6 and 100 constructed in accordance with the from the foregoing, the method of utilization thereof will be briefly described. As seen best in FIGURES l and 2,

in order to place a .plurality of Lexplosive charges within a borehole, such as is normallyy done in a seismic prosn pecting. procedure, 'an appropriate number of containers ofk explosive 26 are secured to the explosive charge holder vided with a severingy means indicated at 46 which includes a wire clip 48 which is formed from a continuous the connection of an actuating line 50 thereto to permit severing of the tape 42 from above ground by pulling upon the line 50 to release the arcuate gripping members 32 to engage the borehole wall 13.

Referring now to the embodiment of the present invention shown in FIGURES 6-8, it will be seen that the explosive charge holder indicated generally at 100 includes a generally cup-shaped body member indicated generally at 112. As seen best in FIGURES 7, the body member 112 includes a generally tubular vertically disposed side wall portion 140` and an imperforate bottom wall portion 160. In the embodiment shown, the body member 112 is sized so as to receive the end of a stick of dynamite such as indicated at 120, however, it will be understood that the inner diameter of the body member 112 may be of any suitable dimension to accept other forms of explosives.

The explosive charge holder 100 is further provided with stabilizing means indicated generally at 130 which includes a plurality of relatively rigid arcuate resilient gripping members 132 which are rigidly secured to the body member 112 such as at 134 by means of welding for example.

As seen best in FIGURES 6 and 7 the arcuate members 132 are preferably secured to the body member 112 intermediate of their ends so as to provide a plurality of youtwardly diverging fingers which project upwardly and downwardly relative to the body member 112 and are thus adapted to frictionally and positively engage the Wall 13 of the borehole 11. Toward this end, the arcuate gripping members 132, preferably formed of spring steel or the like, are cut diagonally adjacent their ends so as t0 provide sharp points 133 adapted to grip the wall 13 of the borehole 11.

The CXPlOSiV .Charge hOlder 100 is further provided kklength of wirepassed aboutthe tape 42 which'wire is f alsofbentto rprovide a loop at the top thereof to facilitate 4G` 10, with a detonating device 26 secured to the top thereof. To place the lowermost charge, as seen in FIGURE l,

the downwardly projecting arcuate resilient gripping with the borehole wall k13a asthe ,charge is pushed downwardly in the borehole'll such aswith a loading pole restrained arcuate resilient gripping members 32 engaging the borehole wall 13.

The uppermost charge as seen in FIGURE 1, which also includes a plurality of explosive filled containers 20 secured to an explosive charge holder 10, is placed within the borehole by first providing the explosive charge holder 10 with the restraining means 40 illustrated in FIGURE 2 so as to permit placement of the explosive charge within the borehole 11 with a loading pole such as 80. When the charge has been pushed to the appropriate point within the boreole 11, which is normally at a point spaced apart from the lowermost charge, the control cable 50 is pulled to sever the tape 42 thus permitting the downwardly projecting portions of the arcuate resilient gripping members 32 to assume the position shown in FIGURE 1 thus securing the uppermost charge in a manner so as to preclude its displacement from the predetermined position by the forces created on the detonation of the lowermost charge at the bottom of the borehole 11.

It will therefore be seen that when the lowermost charge in the borehole is detonated the sudden expansion of air within the borehole 11 will not substantially displace the uppermost charge due to the fact that the arcuate resilient upwardly projecting portions of the gripping members 32 engage the borehole wall 13. In a similar fashion, when the air rushes downwardly within the borehole 11 subsequent to the detonation of the lowermost charge the uppermost charge will not be displaced downwardly due to the fact that the downwardly projecting portions of the arcuate resilient gripping members 32 likewise engage the wall 13 of the bore-hole 11.

It will therefore be seen that there has been provided an explosive charge holder which satisfies the objects of the present invention and overcomes the shortcomings of many explosive charge holders proposed heretofore. Al-

though not specically discussed, it will nevertheless be understood that the method of utilizing the embodiment of the explosive charge holder 100 shown in FIGURES 6-8 is similar to that discussed with the exception that dynamite sticks are utilized instead of explosive filled containers.

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 combination with an explosive charge, a holder adapted to position the explosive charge within a borehole which comprises a generally tubular cup-shaped body member adapted to receive at least a portion of the explosive charge, stabilizing means secured to said body member and adapted to selectively position the holder within a borehole by gripping the wall of the borehole and adapted to normally stabilize the holder against both upward and downward movement in the borehole, said stabilizer means including a plurality of upwardly and downwardly diverging relatively rigid resilient borehole wall gripping members adapted to normally secure said holder within a borehole at a predetermined point, whereby said holder will be held relatively stationary against upward and downward movement in the borehole during detonation of another explosive charge spaced from the charge held by said explosive holder.

2. The combination of claim 1, wherein said body member is an upwardly opening cup-shaped member including a bottom wall portion provided with an aperture whereby a plurality of explosive lled containers provided with complementary threaded coupling members may be secured to said cup-shaped member by interposing said apertured bottom portion between two threadably coupled explosive filled containers.

3. The combination of claim 1 wherein said body member is an upwardly opening cup-shaped member having an imperforate bottom adapted to receive the lower end of a stick of dynamite and the like, said holder including an upwardly extending rod rigidly secured to said body member, said rod being provided with clip means adapted to grippingly engage the stick of dynamite.

4. The combination of claim 1 wherein said holder includes a selectively releasable restraining means adapted to restrain at least said downwardly diverging gripping members out of engagement with the borehole to facilitate placement of the charge holder at a predetermined point within the borehole, said restraining means including a continuous loop of severable tape, said tape being positioned about said gripping members, and severing means coacting with said tape and operable `from above ground to sever said tape to release said gripping members into engagement with the borehole wall.

5. The combination of claim 1, wherein said outwardly projecting ngers comprise arcuate spring metal gripping members rigidly secured to said body member intermediate their ends.

6. The combination of claim S, wherein the ends of the arcuate spring metal members are provided with sharp points adapted to assist in engaging the borehole wall.

7. An explosive holder adapted to position an explosive charge within a borehole which comprises a generally tubular cup-shaped body member adapted to receive at least a portion of the explosive charge, stabilizing means secured to said body member and adapted to selectively position the holder within a borehole by gripping the wall of the borehole and adapted to normally stabilize the holder against both upward and downward movement in the borehole, said stabilizer means including a plurality of upwardly and downwardly diverging relatively rigid resilient borehole wall gripping members adapted to normally secure said holder within a borehole at a predetermined point, whereby said holder will be held relatively stationary against upward and downward movement in the borehole during detonation of another explosive charge spaced from the charge held by said explosive holder.

References Cited UNITED STATES PATENTS 1,220,208 3/1917 Ellis l02-24 1,560,815 l1/1925 Hill IGZ-21.8 X 2,450,366 9/1948 Williams 102-21.8 X 2,965,031 12/1960 Johns 175--4.52 3,046,886 7/1962 Joslin IGZ-21.8

BENJAMIN A. BORCHELT, Primary Examiner. V. R. PENDEGRASS, Assistant Examiner.

Claims (1)

1. IN COMBINATION WITH AN EXPLOSIVE CHARGE, A HOLDER ADAPTED TO POSITION THE EXPLOSIVE CHARGE WITHIN A BOREHOLE WHICH COMPRISES A GENERALLY TUBULAR CUP-SHAPED BODY MEMBER ADAPTED TO RECEIVE AT LEAST A PORTION OF THE EXPLOSIVE CHARGE, STABILIZING MEANS SECURED TO SAID BODY MEMBER AND ADAPTED TO SELECTIVELY POSITION THE HOLDER WITHIN A BOREHOLE BY GRIPPING THE WALL OF THE BOREHOLE AND ADAPTED TO NORMALLY STABILIZE THE HOLDER AGAINST BOTH UPWARD AND DOWNWARD MOVEMENT IN THE BOREHOLE, SAID STABILIZER MEANS INCLUDING A PLURALITY OF UPWARDLY AND DOWNWARDLY DIVERGING RELATIVELY RIGID RESILIENT BOREHOLE WALL GRIPPING MEMBERS ADAPTED TO NORMALLY SECURE SAID HOLDER WITHIN A BOREHOLE AT A PREDETERMINED POINT, WHEREBY SAID HOLDER WILL BE HELD RELATIVELY STATIONARY AGAINST UPWARD AND DOWNWARD MOVEMENT IN THE BOREHOLE DURING DETONATION OF ANOTHER EXPLOSIVE CHARGE SPACED FROM THE CHARGE HELD BY SAID EXPLOSIVE HOLDER.

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