US3822456A

US3822456A - Strand connecting method

Info

Publication number: US3822456A
Application number: US00260699A
Authority: US
Inventors: R Petruzzi
Original assignee: Anaconda Co
Current assignee: Ericsson Inc
Priority date: 1970-03-30
Filing date: 1972-06-07
Publication date: 1974-07-09
Anticipated expiration: 1991-07-09

Abstract

In a hydraulic press for connecting cable strands the penetration of the rams is positively determined and equalized by spacers that attach to the ram guides and limit the hydraulic piston stroke. In this method of using a ram press sufficient pressure is always applied to rams to obtain preselected equal depth of penetration.

Description

Petruzzi 1 July 9, 1974 STRAND CONNECTING METHOD [56] References Cited [75] Inventor: Rudolph E. Petru zzi, Bronxville, U E ST TES P TENTS 2,182,663 12/1939 Eb et al 72/402 Assigneez The Anaconda p ny, New 2,372,029 3/1945 Stair 72/446 Primary Examiner-Charles W. Lanham [22] Filed: June 7, 1972 Assistant Examiner-James R. Duzan [211 App! No: 260,699 Attorney, Agent, or FirmVictor F. Volk Related US. Application Data 57 ABSTRACT [62] Division of 2326.114 Mamh 19701 In ahydraulic press for connecting cable strands the b I penetration of the rams is'positively determined and v I equalized'by spacers that attach to the ram guides and [52] us. c1....,.. 2,129/1 528,z9/ g z gg f 1111111 the hydraulic piston stroke. In this method of [51] Int Cl 4/3/00 using a ram press sufficient pressure is always applied d t t 58 Field 01 Search 29/628; 72/402, 401, 403, ar btam preselecteq equal ep h Pena i 2 Claims, 3 Drawing Figures o l'1'1l11 20 M, 29

{ mam 9:974 3,822,456

g V m INVENTOR.

RUDOLPH E. PETRUZZI BY /7W ///5 MA /W ll I . 1 1 STRAND CONNECTING METHOD This is a division of application Ser. No.'23,6l 1 filed Mar. 30, 1970, now abandoned.

BACKGROUND OF THE INVENTION of the sleeve to make 16 or more indents, depending on r the size of the strand and the strength required in the splice. When a copper sleeve is being used to connect stranded copper conductors a hand pump will supply sufficient pressure to the rams. A pressure gage, -asso ciated with the pump, indicates the pressure and it has been the usual practice to vary the pressure by reference to this gage to make splices of different sizes, using different wall thickness sleeves. Persons who made splices were instructed to follow a prepared schedule of hydraulic pressure corresponding to the particular size of splice, for if the pressure were too great, one or more of the rams might puncture the sleeve, and if it were too low there would be insufficien gripping of the sleeve against the strand.

This known apparatus and method of splicing has not proven satisfactory, however, since it has not resulted in equal penetration of each of the four rams into the sleeve during one application, or in different depths of penetration of the rams atdifferent sections along the sleeve. This deficiency can be accounted for by variations in hardness and compactness of the strands them-' selves, variations in hardness of the sleeve metal, variations in machining of the ram faces or variations in the piston areas to which the hydraulic fluid is being applied.

By means of my invention I propose to increase the reliability of strand splices.

l further propose'to insure that the indentations in connector compression sleeves "have uniform, preselected depths.

I further propose to achieve, the aforesaid advantages in strand splices by means of inexpensive improvement in available apparatus.

I further propose my invention to'be quickly and inexpensively adaptable to different splice sizes.

SUMMARY My invention relates to an improvement in hydraulic presses for connecting strands by means of a metal sleeve. Such pressescomprise at least one ram forradi ally penetrating the sleeve and guide means for the ram that is radially adjustable to fit the sleeve. My improvement comprises spacer means detachably mounted on the guide meanswhich combines with the guide means to limit the penetration of the ram into the sleeve. When the guide means comprises a borefor the ram my improvement comprises a counterbore, preferably threaded, that accomodates an annular spacer means through which the ram can pass into the sleeve. My improvement has particular application to a press com- 2 prising a plurality of hydraulic cylinders, means for mounting the cylinders at intervals around a compression sleeve, and cylindrical ram guides adjustably fitted in each of the cylinders, with a ram being slidable in each of the cylinders. Piston means are associated with each of the rams for urging it into the sleeve and the press includes a supply of hydraulic fluid with pump means for urging the fluid against the piston means within the cylinders; Here my improvement comprises threaded counterbores in the ends of each of the guides facing the sleeve, and a like plurality of spacers, each comprising a flange or other'extension abutting the guide and a threaded projection fitting into the counterbores, the thickness of the extension and thelength of the guides combining to limit the stroke of the pistons to a predetermined penetration of the rams into the sleeve. The extensions of the spacers are substantially equal and my improvement comprises at least one additional like plurality of spacers comprising extensions differing from the extensions of the first named plurality of spacers.

My method of connecting strands comprises the steps of fitting a metal sleeve having a preselected wall thickness over the opposing ends of the strands and adjusting the stroke of each of therams of a multiple ram hydraulic press for a'penetration between IOO-and 175 percent,and preferably percent of .the'wall thickness of the sleeve. Theserams'each has a area of pene-' tra'tion limited to less than the section area of the underlying strand. I then apply pressure in the press in excess of the pressure that would be required to force a plurality of the rams to compress the sleeve and the strands for the full adjusted stroke, thereby pressing the pluralityof rams at spaced intervals around a section of the sleeve surrounding oneof the strands.

I BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows an apparatus, with a splice in section, comprising my invention. i

FIG. 2 shows a sectionalized detail of one of the cyl inders of the apparatus of FIG. 1.

FIG. 3 shows, in section, a plurality of sets of spacers of. my invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring first to FIG." I'an apparatus, indicated generally by thenumeral 10, is shown indenting a splice sleeve 11 around a section of strand 12, which, in the desired rams and cylinders may vary according to the with more than four rams. However, where only a single or double ram press is available my improvement will also have utility, as will be made evident from its further description.

Pressure for the hydraulic fluid in the cylinders 17-20 is supplied by a hand-pump 22 or other known pressure means through a distributor 23 and

pressure hoses

24,25,26,27. A gage 28 indicates the pressure in the system and a conventional pressure relief valve 29 is associated with the pump 22.

lndents made by the rams 13-16 are required to have substantial depth in order to give adequate strength and permanence to the splice. This depth d generally should exceed the wall thickness of the sleeve 11 and I prefer a depth d of about 150 percent of the sleeve wall. But if the depth exceeds 175 percent there is danger that the rams will puncture the wall.

The press is intended for application to splices of different sizes and each of the cylinders 17-20, comprises a ram guide 31 (FIG. 2) with external threading 32 matching internal threading 33 of the cylinders. By turning the ram guides 31 into the cylinders 21 close fit of the press is obtained around the sleeve 11, and the sleeve can be properly centered in the press. As shown in FIG. 2 the ram is widened to form a piston 34 slidable in the smooth, unthreaded, upper portion 36 of the cylinder 17 under pressure of fluid 37 confined by a gasket 38. A spring 39 returns the piston when the pres sure is released by means of the valve 29.An essential element of my invention comprises

spacers

41,42,43,44 for the attachment of which to the guides 31 I have countersunk the guide 31 at 46 and provided internal threading 47. In prior art devices a face 48 of the guide 31 which, of course, was not countersunk, was adjusted into position against the sleeve 11 and, when different penetration depths d were required due to different sleeve wall thicknesses, it was attempted to make the adjustment by varying the cylinder pressure so that in most cases the piston would not take its full stroke.

The stroke of the piston 34 is limited by a top surface 50 of the guide 31 abutting a lower surface 49 of the piston. The total possible penetration of the ram 13 will be the distance I as shown in FIG. 2. In FIG. 3 I have shown a plurality of sets of

spacers

51,52,53 each set being a plurality equal to the number of cylinders in the press 10, four in the illustrated case. Each of the spacers 41 has an extension 54 beyond the face 48 which preferably, but not necessarily, takes the form of a flange 56. The flanges of each of the

sets

51,52,53 of spacers has a different thickness so that by inserting the proper set of spacers, and always applying the maximum pressure, positive equal penetration of the rams can be obtained to any preselected value.

OPERATION In the operation of apparatus comprising any improvement, or the method of my invention the two ends of strands to be spliced are inserted into a sleeve 11 having a preselected wall thickness and a set of spacers 41 having the proper flanges 56 are inserted into the guides 31 to provide a penetration d of about 150 percent of the sleeve wall thickness. The quides 31 are then turned within the cylinders to have the proper projection to receive the sleeve 11. One side 57 of the frame 21 is separable, by removing bolts 58,59 so that the frame can be removed after the splice has been completed. In splicing a sectorized electric cable conductor the frame is adjusted so that the impressions will center on the sectors of one of the strands. The pump 22 is actuated to show. maximum pressure at the gage 28 forcing the rams into the sleeves at equally spaced points around one section of the splice and the pressure is released by means of the valve 29. The frame 21 is then shifted to another section of the sleeve and twisted somewhat to follow the helical path of the sectors and the pressure again applied. This second application may occur over the second strand or two or three sets of impressions may be made in the sleeve over each strand, according to the strength required in the splice.

I have invented an apparatus improvement and method of which the foregoing description has been exemplary rather than definitive, and for which I desire an award of Letters Patent as defined in the following claims.

I claim:

1. The method of connecting two strands by means of a multiple-ram hydraulic press having a plurality of ram guides comprising the steps of:

A. fitting a metal sleeve having a preselected wall sleeve and said strands for a full adjusted stroke absent said spacers, and

E. thereby pressing said plurality of rams spaced intervals around a section of said sleeve surrounding first one and then the other of said strands.

2. The method of claim 1 wherein said penetration is about percent of said thickness.

Claims

1. The method of connecting two strands by means of a multipleram hydraulic press having a plurality of ram guides comprising the steps of: A. fitting a metal sleeve having a preselected wall thickness over the opposing ends of said strands, B. attaching a plurality of detachable spacers to said ram guides C. By means of said spacers adjusting the stroke of each of said rams for a penetration between 100 and 175 percent of said thickness, said rams each having an area of penetration less than the section area of the underlying strand, D. applying pressure in said press in excess of that required for a plurality of said rams to compress said sleeve and said strands for a full adjusted stroke absent said spacers, and E. thereby pressing said plurality of rams spaced intervals around a section of said sleeve surrounding first one and then the other of said strands.

2. The method of claim 1 wherein said penetration is about 150 percent of said thickness.