US2071709A - Wire strand - Google Patents

Description

H. w. RIDDLE Feb. 23, 1937 WIRE STRAND Filed Feb. 21', 1936 lizveiztait' HfiEl E) /4 E/00LE,

Patented- Feb. 23,- 1937 PATENT OFFICE 2,071,709 WIRE STRAND Harvey W. Riddle, Worcester, Mass., assignor to The American Steel and Wire Company of New Jersey, a corporation of New Jersey Application February 21, 1936, Serial No. 65,152 3 Claims. (c1.'1'17 1s This invention relates .to wire rope and, in general, strands of intertwisted wires, the object being to provide smoother surfaces than result from the use of circular wires without at the same time shortening the service life of the product. Other objectsmay be inferred.

Wire ropes are made of intertwisted strands Y of intertwisted wires. When these wires are cirparticularly subject to fatigue failures.

cular they canbe laid into place without being rotated about their axes and are therefore not How.- ever, it is frequently desirable to produce a rope or strand having a smoother surface than can be provided by circular Wires. Then the use of non-circular or shaped wires is resorted to, these forming the outer strand layer's. Quite frequently keystone shapes are used.

Now in fashioning such shaped wires into a strand it is necessary to rotate them about their axes while intertwisting or laying them in their proper relationship, since it would not otherwise be possible to position them with their smooth surfaces, facing outwardly. This places these shaped wires under rotative strains which causes them to become very lively when the strands are severed, imparts an undesirable stiffness to the strands and markedly reduces the fatigue resistance of the strands. All of these undesirable characteristics are quite naturally imparted to any rope made by intertwisting such strands.

It has been proposed that circular wires be in tertwisted into a strand and that this strand be subsequently passed through longitudinal rolling rolls having a circular pass of a lesser diameter,

the idea being that this will deform the wires and smooth the strand surface. But since the strand wires are helical and the rolling direction is longitudinal, the strand-wires are worked or deformed in transverse directions, this placing them under transverse strains or, in other words, rotating strains. Obviously, this proposal does not provide a remedy; It is otherwise objectionable in that deformation cannot be limited to the outside wires, theentire strand being de-- formed whereby the undesirable rotating strains are also introduced, to some extent at least, to the inside wires.

According to the present invention, wires are intertwisted into strands in the conventional manner. That is to say, a conventional stranding machine may be used wherein the wires are fed from spindles carried by gimbals mounted by a rotative frame. This results in the production of a strand of the conventional character, all of the strand wires being free from rotating strains ing already been described.

' from intertwisting which are present in all cases except dead-lay constructions. Subsequently, metal is removed from the outsides of the strands and hence from the outer ones of the wires 5 forming the strands, to smooth the outer surfaces of the strands by imparting non-circular shapes to these outer wires of the same.

The above provides smoother strand surfaces than can be provided by the original circular shapes of the outer strand wires yet introduces no rotating strains. Consequently, the resulting strands are as flexible as any conventional wire strands and are no more subject to fatigue fail,- ures. When these strands. are intertwisted to form wire ropes these ropes have, of course, the same desirable characteristics.

Removal of the metal may be effected by a rotating abrasive wheel located beyond the forming die of a stranding machine. Suitable machining 20 devices may also be used. However, in no in- ,stance should the forming be done by deformation of the strand wires, particularly when such deformation is longitudinal to the axis of the strand, the troubles incidental to so doing hav- 25 The described method results in a strand of intertwisted wires wherein at least those of the strand wires forming the surfaces of the. strand are shaped other than circular to provide a smoother surface than can round wires and yet 30 they'have crystalline structures free from transverse working deformation. Furthermore, 'the wires forming the surfaces of this strand are substantially free from rotating. strains. When a plurality of such strands are intertwisted to form a rope it is obvious that their characteristics are imparted to this rope to an equal extent.

The accompanying drawing serves to illustrate the various features of the invention, Figure 1 be- 40 ing a fragmentary showing of the rope and Figure 2. illustrating as'tranding machine adapted to' the invention. v

In Figure 1 the numeral l indicates the outside strand wires and the numeral 2 the inside ones. The wires are of different sizes, as is usual in 19-wire Scale patent constructions. The wires I were originally circular in shape but the drawing shows them as they appear after the removal of metal from them to impart non-circular 5 shapes having outside surfaces l that are curved to the radius of the strand.

This figure is a fragment of a wire rope made by intertwisting a number of the new strands. Enough is illustrated to show the greater con- 55 tact areas between adjacent strands. The numeral 3 indicates the working surface of a sheave of the proper contour for the illustrated rope and serves to show the broader contact areas the rope presents this surface. As previously mentioned, the wires I have crystalline structures entirely free from transverse working deformation and are free from rotating strains. I

The second figure shows a conventional stranding machine including the rotating cage 4 carrying spools of Wire 5 by way of gimbals 6, the wires from these spools being intertwisted in a die I. The resulting strand leaving the die 1 is worked by a revolving abrasive wheel 8 mounted and powered in any suitable manner. The work performed is that previously described. This figure is included primarily to show the ease with which the conventional method of manufacture may be adapted to the principles of the present invention.

I claim:

1. A method including intertwisting circular wires into a strand and removing sufiicient metal from at least some of the outer ones of said wires to make them non-circular.

2. A method including intertwisting circular wires into a strand and subsequently removing suificient metal from the outer ones of said wires to produce a smoother strand surface than can be provided by their original circular shapes.

3. A method including intertwisting circular wires into a plurality of strands, intertwisting said strands into a rope and subsequently removing metal from those of said wires forming the surface of said rope to produce a smoother rope surface than can be providedby the original circular shapes of said wires.

HARVEY W. RIDDLE.

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