US2266357A - Releasable cable head - Google Patents

Description

Dec. 16, 1941.

A. C. H. COOKE RELEASABLE CABLE HEAD a ma Filed Nov. 21,

IN VEN TOR (1/1 COOAf Patented Dec. 16, 1941 UNITED STATES PATENT OFFICE 2,266,357 RELEASABLE CABLE HEAD Arthur C. H. Cooke, Oklahoma City, Okla., as-

signor to Lane-Wells Company, Los Angeles, Calif., a corporation of Delaware Application November 21, 1939, Serial No. 305,503

3 Claims.

My invention relates to releasable cable heads, and among the objects of my invention are:

First, to provide a releasable cable head which is particularly designed for conductor core wire ropes used to support and supply electricity to oil well tools such as gun perforators;

Second, to provide a releasable cable head which is adapted to be lowered to great depths in liquid-filled well bores and which is so arranged that should the tool to which it is connected become lodged in the well bore, a predetermined tension calculated to pull the cable from the cable head may be applied thereon,

. such tension being substantially below the safety factor of the cable itself so that the cable is in no way damaged;

Third, to provide a releasable cable head which is particularlysatisfactory for releasing a cable from a gun perforator that has become sanded in a well bore, inasmuch as only the cable itself is retrieved without any enlargement at its lower end so that the cable may be readily drawn upward through the sand that may be packed above the gun and around the cable;

Fourth, to provide a releasable cable head which is particularly easy to fasten to an electrical conductor cable for the use of simple tools so that the operation may be accomplished in the field;

Fifth, to provide a releasable cable head which, although assembled on a cable in the field, may be depended upon to release within very close proximity to the predetermined releasing tension and which may .be used repeatedly without deteriorating or tending to pull loose under a load less than the predetermined tension; and

Sixth, to provide a cable head which is an improvement on Patent 2,043,341.

With the above and other objects in view, as may appear hereinafter, reference is directed to the accompanying drawings, in which:

Figure 1 is a longitudinal partial sectional, partial elevational view of my releasable cable head;

Figure 2 is an enlarged fragmentary, longitudinal sectional view through 22 of Figure l; and

' Figure 3 is a plan or end view of the strand dividing head.

The cable I or wire rope with which my releasable cable head is adapted to be used is of the hauling or hoisting type with a conductor core 2 substituted for the usual hemp core. Around the core is provided a plurality of multiple wire strands 3. Each multiple wire strand comprises a central king wire, around which is twisted other wires 5. The cable is preferably of the "preformed type.

The cable head comprises a case 5 having relatively heavy walls and a substantially uniform bore. One end of the bore is threaded to receive the threaded end of a sleeve 1. The sleeve 1 has a bore approximating the diameter of the cable I, which bore is flared at the lower or inner end of the sleeve, as indicated by 8. The case and sleeve form a housing and the inner end of the sleeve forms an abutment;

A spreader plug 9 in the form of a cylindrical block is adapted to fit within the bore of the case 6 and bear against the inner end of the sleeve 1. The spreaderplug 9 is provided with a central core-receiving bore l0, around which are drilled a plurality of strand-receiving bores ll, one for each strand 3. The inner end of each strand-receiving bore is reduced in diameter to form a king wire bore l2.

The several strands 3 of the cable are unwound to expose a length of core 2 and the several planetary wires 5 surrounding each king wire are peeled back and cut off so that each of the king wires 4 is exposed. Care is exercised in removing the wires 5 to prevent scratching or nicking the king wires, and the exposed ends of the king wires are doubled back against themselves to form loops l3, this being done over a smooth, rounded tool so that no nicks or other sources of stress concentration are formed. Before looping the king wires the strands 3 are inserted in the bores II and the king wires are thrust through the bores I2. Also, the core 2 is extended through the bore [0. Naturally, the operations previously described are performed after the cable has been extended through the sleeve 1 and case 6.

The core-receiving bore I 0 is threaded to accommodate a core-receiving tube H which ex-.

tends in the same direction as the loop ends of the king wire. After'the cable has thus been joined tothe spreader plug or block 9 the spreader block is drawn into the case 6 until it seats against the inner end 'of the sleeve 1. The flared end 8 of the bore through the sleeve forms a chamber whereby the several strands may spread from the normal diameter of the cable to the axes of the several strand-receiving bores ll.

After the plug is in place a predetermined quantity of zinc or other relatively soft material is melted and poured around the core-receiving tube ll, so as to completely cover the looped end I3 of the king wires. 'Ihezinc or similar material, when hardened, forms an anchor plug 15.

The extended end of the case 6 is-enlarged slightly and internally threaded to form a shoulder for receiving a terminal disc I 6 and a threaded retainer nipple H. The terminal disc is provided with a terminal i8 extending therethrough for electrical connection to whatever tool is attached to the case 6, while the inner end is attached to the conductor within the core 2. An extra length of the core is provided which is coiled in the space between the terminal disc l6 and the anchor'plug i5. Before positioning the terminal disc this space is completely filled with an insulating compound IS,"

the compound being poured in while in a molten state. When the compound is hardened the space above the terminal disc is completely filled with solid so that neither the anchor plug nor spreader plug 9 can move inwardly by reason of excessive external pressure exerted by the liquid in which the'cable'is immersed.

By reason of the spreader plug or block 9,

tension will be less than that of the safe tensile load on the cable, but also that the releasin tension be uniform and predictable. Tests have shown that the manner in which the king wires are supported and guided by the spreader plug or block issuch that a very uniform pull-out or releasing tension is assured. Furthermore, by reason of the fact that the strands 3 fully protect the king wires, particularly within the chamber 8, although the cable head is used repeatedly the king wires do not become damaged and fail at a lower point than the-desired pull out load.

Various changes and alternate arrangements may be made within the scope of the appended claims, in which it is my intention to claim all novelty inherent in the invention as broadly as the prior art permits.

I claim: v

1. The combination with a. multiple stranded wire rope wherein each strand includes a king wire and several planetary wires wound therearound the king wire extending beyond its planetary wires, of a load-limiting wire rope head comprising: a housing having a bore adapted to receive the wire-rope and a counterbore continuing from said bore and forming therewith an abutment; a spreader block adapted to bear against said abutment and having guide ..ho1es therethrough to accommodate said king .wires only; and means for anchoring the protruding ends of said king wires; said guide holes being arranged to protect said king wires against all but tensile strains whereby the full tensile strength of the king wires may be developed,

said king wires constituting the sole connection to bear against said abutment, said: spreader block having sockets adapted to receive said strands, and guide holes continuing axially from said sockets and adapted to receive the extended portions of said king wires; and a molded anchor covering the protruding ends of said king wires; said king wires being held in coaxial relationship with their respective strands and said king wires continuing axially into said anchor, whereby said king wires are adapted to develop their full tensile strength before giving way, said king wires constituting the sole connection with said head.

3. The combination with a multiple stranded wire rope wherein each strand includes a king wire and several planetary wires wound therearound said king wires extending beyond said planetary, wires, of. a load-limiting wire rope head comprising: a housing 'having a 'bore adapted to receive snugly the entire cable\ and flaring into an enlarged counterbore, there being formed, however, a peripheral abutment; a

spreader block adapted to bear against said abutment, said spreader'block having sockets adapted to receive said strands, and guide holes continuing axially from said sockets and adapted toreceive the extended portions of said king wires; a molded anchor covering the protruding ends of said king wires; said king wires being protected by their planetary wires throughout the flared portion of said wire rope-receiving bore and said sockets; said king wires being held sile strength before giving way and releasing said head.

. ARTHUR C. H. COOKE.

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