METHOD OF PREPARATION OF WIRE SURFACE BEFORE DRY DRAWING Russian patent published in 2003 - IPC

FIELD: preparation of surfaces of high- and low-carbon wire before dry drawing; production of metalware. SUBSTANCE: surface of wire is subjected to etching in sulfuric acid solution at concentration of 150-220 g/l and temperature of 70 to 75 C or in hydrochloric acid solution at concentration of 100-220 g/l and temperature of 18 to 25 C followed by washing. Then, under-lubricant coat is applied in solution at the following ratio of components, g/l: borax pentahydrate Na₂B₄O₇•5H₂O, 60.0-90.0; sodium tripolyphosphate Na₅P₃O₁₀ or trisodium phosphate Na₃PO₄, 8.0-12.0; sodium sulfate Na₂SO₄, 13.0-35.0; sodium carbonate Na₂CO₃, 3.0-11.2; bone glue (hide glue, joiner s glue), 0.01-1.0 and water being the remainder; application of coat is performed by dipping the wire in working solution at temperature of 85-95 C for 1-5 minutes followed by keeping it in the air for 15-40 s and repeated dipping for 1-5 minutes or by drawing the wire through solution at temperature of 85-95 C for 10-40 s. EFFECT: enhanced antifriction properties; enhanced stability of coat.