我厂生产的70型汽车发动机缸体采用HT21-40铸铁,经过退火处理,长期以来,耐磨性不够稳定。为了保证缸体的质量,过去一直采用缸体镶套的办法。这样,机械加工工作量大大增加,成本相应提高。为了寻求比镶套更好的办法,热处理车间与装备车间革命职工,在车间党支部的领导和支持下,发扬敢想敢干的革命精神和实事求是的科学态度,自力更 I plant production of 70 engine block using HT21-40 engine cast iron, after annealing, long-term, not enough wear resistance and stability. In order to ensure the quality of the cylinder block, the cylinder block has been used in the past. In this way, the workload of machining increases greatly, the cost increases accordingly. In order to find a better way than the mosaics, the revolutionary workers in the heat treatment workshops and equipment workshops should carry forward the revolutionary spirit of daring to dare and seek truth from facts under the leadership and support of the Party branch of the workshop,