2空气压缩机生产能力为100米~3/分压缩空气,气缸体重4.5吨,材质为苏联牌号21-40,相当于我国标准20-40(灰铸铁),是五十年代引进的设备。一九七五年我厂的一台2空气压缩机内缸壁根部过渡圆角处发现一条约480毫米长的裂纹(图1中A),泄漏严重,致使全套设备停产。一九八○年沈阳某厂也有一台同样设备在气缸内壁中间部位发现四条裂纹,总长度达900毫米(图1中B),停产达半年之久。我们对这些裂纹进行 2 air compressor production capacity of 100 m ~ 3 / min compressed air, the cylinder weight 4.5 tons, made of the Soviet Union grade 21-40, equivalent to China’s standard 20-40 (gray cast iron), is introduced in the fifties equipment. In 1975, a 480-mm-long crack (Figure 1, A) was found in the transitional fillet of the root wall of an internal air compressor of a 2-air compressor in our factory. The leak was so serious that the complete set of equipment was discontinued. In 1980 a factory in Shenyang also had four similar cracks found in the middle of the cylinder wall with a total length of 900 mm (B in Figure 1). The production was stopped for six months. We deal with these cracks