US2618999A

US2618999A - Charge setting device

Info

Publication number: US2618999A
Application number: US48222A
Authority: US
Inventors: David H Scott
Original assignee: Texaco Inc
Current assignee: Texaco Inc
Priority date: 1948-09-08
Filing date: 1948-09-08
Publication date: 1952-11-25
Anticipated expiration: 1969-11-25

Description

Nov. 25, 1952 Filed Sept. 8, 1948 D. H. SCOTT CHARGE SETTING DEVICE l I 36-1 L 32 i;

INVENTOR.

Patented Nov. 25, 1952 CHARGE SETTING DEVICE David H. Scott, Bakersfield, Calif., assi'gnor to The Texas Company, New York, N. Y., a corporation of Delaware Application September 8, 1948, Serial No. 48,222

1 Claim. 1

This invention relates to charge setting devices, more particularly to a device for setting or burying an explosive charge beneath the floor of a body of water. The principal object of the invention is to provide a device through the use of which a hole can be formed in the floor of a body of water and an explosive charge placed in the hole, all in substantially one operation conducted from a boat or barge and without the necessity of using divers.

As is well known to those familiar with seismic exploration in water covered areas it is desirable that the charge or shot be placed several feet at least, below the floor or bottom and this has usually required the services of one or more divers whose work it has been to form the holes and to place the charges therein.

In accordance with the invention a device is provided which can be operated directly from the deck of a boat and by means of which the holes will not only be dug but the charges placed in the holes without the necessity of anyone going below the surface of the water. A tube or pipe is adapted to be suspended vertically in the water from the side of the boat and means are provided for forcing a stream of water under pressure downwardly through the pipe, the bottom of which will be held slightly above the bottom. The lower end of the pipe is shaped so as to produce a jet action in the water issuing therefrom and this water under its high velocity will scour or erode the formation to produce a hole therein, this hole being deepened as the pipe is lowered. During the hole making operation the explosive charge is temporarily fastened to the pipe near its lower end and means are provided for releasing the charge from the pipe when the hole has reached the desired depth so that the charge will remain buried in the hole after the pipe is removed.

For a better understanding of the invention reference may be had to the accompanying drawing' in which:

Fig. 1 is a vertical elevation partly in section of a device embodying the invention;

Fig. 1a is a bottom plan View of the device as shown in Fig. 1;

Fig. 2 is a view similar to Fig. 1 but showing the device in side elevation;

Fig. 2a is a bottom plan View of the device as Referring to the drawing, a tubular member or pipe I8 is provided at its upper end with a re duced section l2, an elbow l4 and a swivel connection E6 to which a hose may be attached. A suitable eyelet I8 is secured to the elbow id for receiving a cable by means of which the pipe member can be suspended in the Water as from the side of a boat. The lower portion 23 of the pipe member I!) is preferably flattened on one side as shown at 22 as by cutting part of the pipe it! lengthwise, removing one side and welding a fiat plate over the remaining side. The lower extremity of the section 23 is tapered inwardly as at 2-3 to provide a restricted opening 26. Within the upper portion of the pipe 39 is a length of smaller pipe 28, this pipe extending from the elbow Hi to the upper end of the flattened or bed portion 28 as is shown more clearly in Fig. 2.

When a suitable hose connection is made to the swivel member 56 and water under pressure is forced into the device, this water will pass downwardly through the inner pipe I3 then through the lower portion 20 and outwardly under high velocity through the restricted opening 26. Assuming that the device is suspended so that its lower end will be positioned slightly above the bottom the water issuing or jetting from the lower end of the device will erode away the earth formation so as to produce a hole therein and as the device is lowered this hole will, of course, be deepened.

As shown in Figs. 3 and 3a, an explosive charge 39 illustrated as comprising three sections disposed end to end is temporariy secured or bound to the flat side 22 of the lower portion 29 of the device as by means of cords or tapes 32. A cord or cable 35 extending upwardly to the surface has its lower end or ends secured to the tapes 32 as by means of rings or snap fasteners 36.

The charge as will be secured to the pipe portion 29 before the device is placed in the water and a suitable lead wire 38 will be attached to the cap or detonator of the charge. The wire 38 will be long enough to reach the surface of the water after the charge has been buried where it will preferably be attached to a suitable buoy.

If desired, a length of wire or cord to shown in Figs. 3 and 3a may be secured to the charge at an intermediate point such as t2 by twisting the wire around the charge or otherwise, and this. wire will extend downwardly and underneath the bottom end 25 of the device and then upwardly along the back side to be secured againt the pipe by means of the lower tape 32. The purpose of the wire or cord at is to prevent the charge from slipping upwardly along the pipe portion 20. The

wire 40 also holds the lower portion of the charge firmly against the charge bed or flat surface 22 to prevent sand or other loose material from wedging in between the charge and the pipe. Were it not for the provision of the wire 40 the sand might wedge in and cause the lower end of the charge to bend outwardly away from the bed 22 with the probable result that a portion of the charge might break away before the burial is completed.

After the charge has been attached to the pipe member, as shown in Fig. 3, the device is lowered into the water, as has been described hereinbefore, to a position such that its lower end will be slightly above the bottom, The water is then forced downwardly through the device and a hole will be formed in the bottom as has been described. When the hole has reached a sufiicient depth the water flow through the pipe is stopped and an upward pull on the cord or cable 34 will break the tapes 32 thus releasing the charge from the pipe member. The pipe can then be withdrawn from the hole and the charge will remain buried therein, the cap or lead Wire 38 extending, as has been described, to a suitable buoy, not shown, at the surface. When the proper electrical connections are subsequently made to the cap wires the charge will be exploded so that the seismic records can be made.

Although the device has been described as made up from a piece of pipe I!) which is subsequently cut and welded or otherwise prepared to provide the lower restricted portion 28 having the flat face or bed 22, it is understood that the device could be made in substantially one piece by merely utilizing the pipe 28 and extending it downwardly and providing a restricted outlet at its lower end so that a jet action would be produced by the water issuing therefrom at high velocity. In that case it would not be absolutely necessary that the fiat surface or bed 22 be provided since the charge could be secured to the outer surface of the round pipe 28.

In one of the charge setting devices of the form illustrated, which has been used successfully, the over-all length of the device was approximately 18 feet, the length of the charge bed 22 was 10 feet, the outside diameter of the pipe 18 was about inches and the weight of this portion of the device was 22.2 lbs. per foot, The outside diameter of the inner pipe 28 was 2 inches and the weight of the entire device less the charge was about 350 lbs.

Although the charge has been described and illustrated as secured to the pipe portion 28 by means of tapes 32 it is to be understood that other suitable attaching means are contemplated. Again, instead of attaching the two lower ends of the cable 34 to the tapes 32 as shown, other means for breaking these tapes may be used. For example, a length of chain attached to the upper end of the restricted portion 29 can hang downwardly through the inside of the tapes 32 and the cable 34 could then be attached to the bottom end of the chain. An upward pull on the cable would cause the chain to break the tapes 32 so as to ends so that any desired number of cans can be screwed together to make a charge of the desired length. Using the device, an example of which is given above, a charge of 30 pounds and substantially 6 feet in length was used. Larger or smaller charges can, of course, be used and attached to the pipe as has been described.

It will be seen that in accordance with this invention a simple and effective device has been provided by means of which a boat having but a very few operators can proceed ahead of the other boats carrying the seismic exploration party so as to set or bury several charges with a minimum of effort and time consumption. The following, or shooting boat need then merely connect a. suitable source of electrical supply to the cap leads 38 which have been left attached to a buoy by the preceding or charge-setting boat, in order to fire the shot.

Obviously many other modifications and-variations of the invention, as hereinbefore set forth, may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claim.

I claim:

A device for setting an elongated explosive seismic charge comparatively small in diameter in a water-covered area comprising an elongated jet pipe, means for lowering and raising said jet pipe vertically in the water over the point where the charge is to be set, said pipe being substantially round in cross section in its upper portion and somewhat flattened in its lower portion to provide a restricted opening in its lower end, means for forcing water under pressure downwardly through said pipe so that said water issuing at high velocity from the restricted end of the pipe will erode the earth and form a hole therein as said pipe is lowered, binding means including a tape-like element for detachably securing said charge to the xterior of the flattened portion of said pipe, and means for disrupting said binding means so that the charge will be disengaged from the jet pipe to remain in said hole when the jet pipe is withdrawn, said lastnamed means comprising a cable extending downwardly from the surface and attached to said tape-like element and adapted to be pulled upwardly to break said element.

DAVID E. SCOTT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 7 Number Name Date 230,145 Moses July 20, 1880 277,695 Edson May 15,1883 476,757 Miller June 7, 1892 494,877 Miller -Apr. 4,1893

1,222,938 Dryson Apr. 17,-1917 1,560,038 Camp -1- Nov. 3- 1925 1,753,860 Hahneman Apr.= 8, 1930 2,048,677 Berteling July 28,1936

2,137,261 Boll et al Nov. 22, 1938 FOREIGN PATENTS Number Country Date 125,464 Great Britain of 1919