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由于我国工矿业和科学技术的飞速发展天平的需要日益广泛,生产方面为了书约金属材料,有使用铸铁代替铜合金的,有使用普通塑料做刀垫架的,有使用胶合物料做立柱的。我们考虑天平部件的材料,要求物理性能好,国内有产品,加工不困难。就目前各种塑料中,找制造天平主要部件的金属代用品,是我们的一个方向,但选用哪一种好,必需慎重考虑。我先介绍硬聚氯乙烯和聚四氟乙烯两种塑料的性能。(注) 一、硬聚氯乙烯塑料,分子式CH_2CHC_1 比重 1.40 抗张强度≥400公斤/平方厘米;
Due to the rapid development of industry and mining and science and technology needs of the balance increasingly wide range of production for the book about metal materials, there is the use of cast iron instead of copper alloy, the use of ordinary plastic scaffolding, the use of glued material column. We consider the balance of the components of the material, requiring good physical properties, domestic products, processing is not difficult. In the current variety of plastics, looking for the manufacture of the main components of the metal substitutes, is one of our direction, but which one is good, we must carefully consider. Let me introduce the properties of two kinds of plastics, PVC and PTFE. (Note) First, the rigid PVC plastic, molecular weight CH_2CHC_1 1.40 Tensile strength ≥ 400 kg / cm;