GB1196662A - Improvements in or relating to the Heat Treatment of Wire and Other Elongated Metal Elements - Google Patents

Abstract

1,196,662. Heat-treating elongated metal elements. G.K.N. SOMERSET WIRE Ltd. Feb. 26, 1968 [Feb.24, 1967], No.8808/67. Heading C7N. An elongated metal element, e.g. carbon-or alloy-steel wire strand or rope, strip or rod, is heat treated, e.g. tempered after oil quenching, stress relieved after drawing or hot stretched, by advancing the element, e.g. steel wire 21, in straight configuration first into a heated liquid bath, e.g. a salt or lead bath 10 contained in an inclined tube 11, through an orifice e.g. of a WC die 19 in an upstanding end wall 18 of the bath, the orifice being disposed below the liquid surface level 10a and of bore greater than the diameter of the element by an amount sufficient to permit free passage of the element through the orifice, then to and through the liquid surface level 10a. During advancement, a force is applied to the liquid in a direction to resist its leakage out of the bath between the advancing element and the adjacent wall of the orifice. The bore of the orifice may be e.g. 0.060 inch just greater than the diameter e.g. 0À058 inch of the wire 21, to achieve this force; or the wire may first pass through a chamber supplied with air under pressure surrounding the orifice. For lead patenting, the bath may be maintained at 400-450‹C or at 250-550‹C for a salt bath, by a gas burner pipe 25 with jets 25a. As shown, the open upper end 11c of the inclined tube may be provided with a lip 23 having a notch through which wire 21 is guided out of the bath. Subsequently the wire may pass still in straight configuration through a hot water spray quenching bath 24 prior to coiling on a drum 26.