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一、前言 螺旋桨对铸件质量要求很高,要求铸件机械性能好,在海水中耐腐蚀疲劳强度高,耐空泡腐蚀性能好。我厂铸造螺旋桨的材料大部分是ZHMn55—3—1,这种锰黄铜体收缩大,易生成氧化夹渣及缩孔等缺陷。为了保证螺旋桨质量的稳定,就必须严格执行熔炼工艺和采用特殊的铸造工艺。 二、铸造工艺 1.工艺方案的确定 我厂前一段生产的螺旋桨,废品率比较高,主要的缺陷是夹渣、气孔、几何形状尺寸不符等。其中以气孔(或夹渣)最严重,
I. Introduction Propeller on the castings of high quality, requiring casting mechanical properties, corrosion resistance in sea water, high fatigue strength, corrosion resistance of cavitation is good. Most of our factory casting propeller material ZHMn55-3-1, this manganese brass body contraction, easy to generate oxidation slag and shrinkage and other defects. In order to ensure the stability of the propeller quality, we must strictly implement the smelting process and the use of special casting process. Second, the casting process 1. Determination of process options I plant the first paragraph of the production of propellers, the rejection rate is relatively high, the main drawback is slag, porosity, geometric shape and size does not match. Among them, stomatal (or slag) is the most serious,