US2887053A - Explosive assembly - Google Patents

Description

May 19, 1959 o. A. lTRlA EIAL I EXPLOSIVE ASSEMBLY Filed July 50, 1954 V-M/u 5 Comv: e

91,445 (bums-awe 2,887,053 Patented May 19, 1959 EXPLOSIV E ASSEMBLY Oswald A. Itria, Bellaire, and Harley L. Tanner III, Houston, Tex., assignors to The Texas Company, New York, N.Y., a corporation of Delaware Application July 30, 1954, Serial No. 446,742 2 Claims. (Cl. 102-24) This invention relates to an explosive assembly useful in seismic exploration. More particularly, this invention is directed to an explosive assembly which can be handled with ease and conveniently centrally lowered into a shot hole. An explosive assembly in accordance with this invention is particularly useful in a method of seismic exploration wherein a plurality of spaced apart high explosive charges are progressively detonated in sequence within a shot hole at a rate determined by the seismic velocity of the medium or formation surrounding said spaced charges so as to produce a reinforced seismic wave moving in a desired direction.

In seismic exploration a charge of high explosive is lowered and positioned within a shot hole and then deto nated. Some diificulty is usually experienced in lowering the high explosive charge within the shot hole and in centering the charge therein. It has been the practice heretofore to tape the firing wires and blasting cap or a detonating medium such as Primacord to the explosive charges before lowering the charge into the shot hole. When such a high explosive charge is lowered into a shot hole it is diflicult to keep the explosive charge centrally within the shot hole While the charge is being lowered therein. Frequently the charge hangs up or catches upon the wall of the shot hole. Also, needless to say, the operation of taping a blasting cap, or a length of Primacord, which is an explosive medium to the side of the explosive charge is time consuming and awkward.

It is an object of this invention to provide an explosive assembly which can readily and easily be assembled.

It is another object of this invention to provide an explosive assembly which can conveniently and readily be centrally lowered within a shot hole.

It is still another object of this invention to provide an explosive assembly particularly useful in a seismic exploration operation wherein a plurality of vertically spaced charges are progressively detonated within a shot hole.

In at least one embodiment of this invention at least one of the foregoing objects will be obtained.

How these and other objects of this invention are attained will become apparent with reference to the accompanying disclosure and drawing wherein there is schematically illustrated in partial vertical cross section an explosive assembly in accordance with this invention.

In accordance with our invention We have provided an explosive assembly fitted with terminal connecting means which serve not only as support means for lowering the explosive assembly into a shot hole but also as means for more accurately centering and positioning the explosive assembly within the shot hole. The connecting or supporting means located at the ends of the explosive assembly are adapted to receive and engage a length of material, such as a length of Primacord, so that the explosive assembly may be suspended therefrom. Additionally, another length of Primacord may extend from the other or lower end of the asesmbly. This other length of Primacord may in turn be connected to and hold another explosive assembly. It is apparent from the accompanying drawing that the explosive assembly in accord ance with our invention can be quickly, safely and conveniently put together.

Referring now to the drawing which there is illustrated in partial vertical cross section an explosive assembly made up of cylindrical containers 11 of a high explosive, such as Nitramon, threadedly engaged end to end. The containers 11 of high explosive are provided at one end with an internally threaded recess 12 and at the other end with an externally threaded projection 13. When assembling two or more high explosive containers the internally threaded recess of the container is threadedly engaged with the cooperating externally threaded projection of another container. In this manner a column of high explosive of any desired length may be assembled. These containers 11 of high explosive are manufactured and commercially available substantially as illustrated in the drawing.

An explosive assembly in accordance with our invention, is obtained by threadedly engaging the terminal internally threaded recess 12 of a charge array with a male connector 14 which is provided with an externally threaded projection 15 adapted to threadedly engage recess 12. The other end of the charge array i.e., the terminal externally threaded projection 13, is threadedly engaged with a female connector 16 which is provided with an internally threaded recess 17 adapted to threadedly engage the threaded projection 13 at the other end of the charge array. Each of the connectors 14 and 16 is provided with an opening 19 and 20, respectively extending axially therethrough. The size of the openings 19 and 20 is such that a length of Primacord 21 can conveniently be inserted theretbrough. By knotting the ends 21 of the Primacord which has been inserted through the connectors 14 and 16 into the openings 19 and 20, respectively the charge array can be suspended from a length of the Primacord, the knots being larger than the cooperating openings with the result that the length of Primacord is locked or engaged with its cooperating connector.

Preferably, as illustrated in the drawing, the externally threaded projection 15 of the male connector 14 is recessed 15a to receive the knotted end 21 of the Primacord. In somewhat the same manner the female connector 16 is spaced from the end of the externally threaded projection 13 at the other end of the charge array to provide space for the knotted end of the Primacord associated therewith. In this manner the knotted ends 21 of the Primacord are maintained in close proximity, preferably in direct contact with the respective adjacent end of the charge array.

As is apparent from the drawing, the charge array or assembly can be suspended from a length of Primacord 22. Additional charge arrays in any number desired can conveniently be suspended in a similar manner from the lower length of Primacord 22'. The male and female connectors 14 and 16, respectively, preferably have the same outside diameter as containers 11 to which they are threadedly engaged. The openings 19 and 20 provided within the connectors 14 and 16, respectively, are concentrically located with respect thereto and with respect to their respective adjacent threadedly engaged containers 11. The connectors 14 and 16 may be made of any suitable metal, plastic or wood material which can be machined, cast, stamped or molded.

As will be apparent to those skilled in the art many alterations, substitutions and modifications may be made without departing from the spirit and scope of this invention.

We claim:

1. An explosive assembly adapted for vertical suspension in a shot hole, said assembly comprising containers type of coupling structure, one .complenientaryto, each end, of' a container, s aid connector strnctureinclnding a longitudinal axis adapted for; coaxial alignment vvith the longifu'dinal axesof said containers and said explosive material, an'axiallylocated openingpassing through each of sad I dia'inc tar-lengths of highexplosive,therethrough, a recess each connector on the side adjacent the container for providing space to receive a knot insaid-h igh explosive material, said end connectors having substantially the same outside diameter assaid containers, and said recesse's .heing concentric with said openings.

2, An explosive assembly comprrng a plurality of separate charges having longitudinal axes and beingadapted for vertical su spension .ina shot hole, a plurality of lengths of fiexible high explosivernaterial being the sole connectors between each, of said separate charges for mutual fip rtfli rflqfl sa d l hs. feexpl ivelmate i having" longitudinal axes adapted for axial alishmefltwith the fv said charges, each of said s eparate charges comprising at least one container filled with explosive of connectormembersjor receiving said small material, said container having a longitudinal axis and being provided at one end with a first internally threaded recess and at the other end with a first externally threaded projection, and connector means comprising in combination a first connector having a longitudinal axis adapted for coaxial alignment with the axis of one of said containers and provided at one endwith a second externally threaded projection for threadable engagement with said first recess, said first connectorhaving an axially located opening therethrough for accommodating said .fiexible high explosive material, said axially located opening being enlarged. at the, end adjacent to said first container recess, a second connector having a longitudinal axis adapted for coaxial alignment 'with the axis of one of said containers and provided at one end with a second internally threaded recess for threadable engagement with said first p1' )jecti on, said secondconnector having an axially located opening therethrough for accommodating said;.fiexilple. high explosive material, and said axially located, opening being enlarged at the end adjacent to said first container projection.

References c ten in the file 6r this patent UNITED STATES PATENTS 21,238,939 Lewiset al. Apr. 22, 1941 2,548,946 'Clau'ser et a1 Apr. 17, 1951 2,708,408 '"Swee'trnan May 17, 1955 2,721,617 Piety w", Oct. 25, 1955 I 7 H IFQREIGN PATENTS 493,862 Canada June 23, 1953

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