Abstract：To solve the problem of existing sticky mold in punch pressing upstream pumping grooves on sealing rings of SiC, the study was carried out in the aspects of mold structure, selection of mold release agent, speed of compression and depressurization, et al. The single factor analysis method was used, and lots of test with hydraulic forming machine was conducted for parameters optimization. The results show that the most available structure of mold is a draft angle of 11°-15°on the two sides of the small spiral pieces with a radius of transition fillet with 0.1-0.2 mm on the areas of the bottom corners. Two kinds of combinations were chosen on the selection of mold release agent with their properties and experimental results, one is the combination of molybdenum disulfide of solid lubricant and vaseline, and the other is the combination of lithium base grease and anti-wear hydraulic oil. The appearance of former method is better than latter one, but the process of application is more complicated while the productivity is lower. Pressing speed and holdup time hardly impacts demolding, while depressurization rate has obvious impacts. The optimum depressurization rate is 2-5 MPa/s. In addition, according to the property of SiC and appearance of pumping grooves, the reasons that other kinds release agent cannot meet the requirements were analyzed.
符永宏, 袁志超, 华希俊, 肖开龙, 杨烨刚. 机械密封环上游泵送槽凸模压制脱模工艺试验[J]. 排灌机械工程学报, 2014, 32(6): 500-504.
Fu Yonghong, Yuan Zhichao, Hua Xijun, Xiao Kailong, Yang Yegang. Experimental research on technique of demolding with punch pressing of upstream pumping grooves on sealing rings. Journal of Drainage and Irrigation Machinery Engin, 2014, 32(6): 500-504.
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