拉拔润滑液的质量控制

Quality Control of the Lubrication Solution for Drawing

水系拉拔润滑液在金属拉拔作业中主要起到润滑、减少或控制摩擦、冷却、防止腐蚀等重要作用.采用硬脂酸:月桂酸:烧碱(质量比)=9∶ 1∶ (1.4～1.5)在温度60～70 ℃合成硬脂酸钠,配成5%左右的水溶液可有效用于钢管拉拔.润滑液与金属表面生成的保护性边界润滑膜主要是两种:化学吸附和物理吸附,润滑膜的结构由外向内是皂液(硬脂酸钠)→硬脂酸锌→磷酸锌→钢材.在生产中发现,应控制润滑液的有效物含量≥70%、温度60～70 ℃、pH值=7～9.实践证明,水系拉拔润滑液不仅适用于钢管冷拔,而且适用于线材引伸、板材压延及管件、标准件冷镦等塑性加工行业.

Sodium stearate was synthesized from stearic acid, lauric acid, and sodium hydroxide at a ratio of 9:1:1.4~1.5(in mass). Thus the aqueous solution of the resulting sodium stearate at a concentration of 5% was used as the lubrication solution for the drawing of steel tube. It was suggested to control the pH value of the lubrication solution within 7~9 and the concentration of the efficient constituent not less than 70% in production practice, so as to acquire good lubrication efficiency.