| The cold swaging of fittings on wire rope is a severe
process requiring considerable movement of the steel in
the fitting. The steel in the fitting is forced under great
pressure to flow into the crevices between the wires
and strands of the wire rope and, at the same time, to
elongate parallel to the wire rope. It is for these reasons
that the swaging must be done in multiple pressings.
Dies should be in good condition and must be properly
lubricated. The swaging process must also be done in multiple pressings to eliminate excessive "flashing." The term "flashing" is used to describe the material that extrudes or is squeezed out into the area between the die faces. If "excessive" flashing has been created it will not be eliminated in additional pressings. The "excessive" flash will most likely be folded back in the next pressing and will develop into a definite and permanent mark in the material and possibly a crack. To avoid this situation, the following basic procedure is recommended: Apply lubricant, such as light oil, to both die blocks. Close the die blocks approximately one-half of the distance between first contact with the fitting and full die closure. (See 1 and 2.) Open dies and rotate the fitting 45 degrees to 90 degrees (1/8 to 1/4 turn) and close dies approximately 1/4 of the original A Dimension (See 3 and 4.) Open dies and rotate the fitting 45 degrees to 90 degrees and fully close dies. (See 5 and 6.) It is only necessary to close until lubricant is squeezed out between die faces. Another pressing may be desired to further round the fitting for appearance. Larger fittings may require additional pressings before achieving full closure of the dies. This procedure applies to all Crosby-National swage fittings with the following points of clarification. - The initial pressing of the #506 Duplex Sleeve must be made with the greater dimension of its cross-section in a vertical position.--The #505 Sleeve, 1" and larger, requires pressing in a first-stage die and a second-stage die. Use the before mentioned procedure for both stages. It will be necessary on large size S-501 and S-502 Swage Sockets, because of limited press capacity, to progressively swage the shank. This is done by dividing the shank into equal segments and then, beginning at the rope end of the socket, to completely swage the first segment using the previously mentioned procedure. The next segment is then fed into the dies and completely swaged; this is repeated until the shank has been totally swaged. It is important not to swage beyond the machined portion of the shank. Swaging dies must be inspected periodically. Any scores or nicks should be polished out. Dies showing excessive wear should be replaced. As an aid in determining if the fitting has been swaged to acceptable limits and also indirectly to judge the condition of the die, a table on page 18 lists the maximum OD of the fitting after swaging. This maximum OD dimension takes into account die tolerance, die wear, and material spring-back. |
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