一、前言 鞍钢铸管厂生产的注砂管,是贯彻毛主席关于“独立自主、自力更生”的革命精神,在一九五八年试制成功的。它主要用于采煤回填砂输送管路。随着我国煤炭工业的迅速发展,注砂管的数量和质量远远满足不了形势发展的需要,其主要原因是注砂管的切割加工成了关键工序。 I. Preface The sand injection pipe produced by Ansteel Pipe Plant is the successful implementation of Chairman Mao’s revolutionary spirit of “independence and self-reliance” in trial production in 1958. It is mainly used for coal backfill sand conveying pipelines. With the rapid development of China’s coal industry, the quantity and quality of sand injection pipe far can not meet the needs of the development of the situation. The main reason is that the cutting and processing of sand injection pipe has become the key process.