我们宁波活塞环厂的广大革命职工,通过史无前例的无产阶级文化大革命的锻炼,阶级斗争和路线斗争的觉悟大大提高。在“工业学大庆”的群众运动,革命职工遵循伟大领袖毛主席关于“独立自主、自力更生”和“一切产品,不但求数量多,而且求质量好”的教导,发扬敢想敢干的革命精神,在上级的支持和兄弟单位的帮助下,奋战三个半月的时间,试制成功一台0.5吨无芯工频电炉,并于六月三十日晨熔炼出第一炉活塞环合金铸铁,向党的诞生五十周年献了礼。我厂生产的筒型活塞环,原采用冲天炉熔炼铬钼铜合金铸铁的。用冲天炉熔炼合金铸 The revolutionary workers and staff of our Ningbo Piston Ring Factory have greatly enhanced their awareness of class struggle and the line struggle through the unprecedented exercise of the Great Proletarian Cultural Revolution. In the mass movement “Daqing in Industry”, revolutionary workers, following the guidance of Chairman Mao on “independence, self-reliance” and “all products, not only for quantity, but also for good quality,” carried forward by the great leader Chairman Mao carried forward the revolutionary spirit of daring to think and do. With the support of their superiors and the help of their brother units, they successfully tried out a 0.5-ton coreless electric-frequency electric furnace with a trial of three and a half months and smelted the first furnace piston ring alloy cast iron on the morning of June 30, The fiftieth anniversary of the birth anniversary gift. I plant the production of cylindrical piston rings, the original use of cupola melting chrome molybdenum copper alloy cast iron. Smelting alloy casting with cupola