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

FIELD: methods of preparation of surfaces of high-carbon and low-carbon wire before dry drawing; production of metalware. SUBSTANCE: wire is preliminarily subjected to etching in sulfuric acid solution at concentration of 150-220 g/l and temperature of 60 to 75 C or in hydrochloric acid solution at concentration of 100-220 g/l at temperature of 18-35 C followed by washing. Subsequent application of under-lubricant coat is performed in solution at the following ratio of components, g/l: borax pentahydrate Na₂B₄O₇•5H₂O, 60.0-90.0; sodium meta-silicate Na₂SiO₃•9H₂O, 2.0-3.0; trisodium phosphate Na₃PO₄, 5.0-7.0; fluorine compound, 10.0- 15.0; sodium sulfate Na₂SO₄, 10.0-15.0; sodium carbonate Na₂CO₃, 13.0-19.5 and water being the remainder; procedure is performed by dipping wire in working solution at temperature of 80 to 95 C for 2 to 10 minutes or by drawing wire through solution at temperature of 85 to 100 C for 10 to 40 seconds. EFFECT: improved antifriction properties of under-lubricant coat; enhanced stability of drawing tools.