在毛主席亲自制定的“鞍钢宪法”光辉旗帜指引下,我厂铸造工人自一九六八年以来,对截止阀铸件采用硬型生产的新工艺进行了试验,经一年多的实践,初步掌握了手工操作硬型生产工艺,为组织流水线生产提供了经验。接着,于一九七一年,经过半年的奋战,正式建成了截止阀铸件的硬型流水生产线。目前,能上线生产的铸件已达25种,其中小的重400克,大的重3公斤,而且全部是下芯的铸件。现将生产情况简介如下。一、硬型的制造铸件的精度和光洁度直接受硬型的精度和光洁度的影响,因而必须保证硬型有 Guided by the glorious banner of “Anshan Iron and Steel” Constitution, which Chairman Mao personally formulated, our foundry workers have experimented with hard work on the production of globe valve castings since 1968. After more than a year of practice, Mastered the manual production of hard-type process, for the organization of production lines provided the experience. Then, in 1971, after half a year’s hard work, a hard-type assembly line for valve castings was officially established. At present, there are 25 kinds of castings that can be put into production online, of which the small ones weigh 400g and the big ones weigh 3kg, all of which are the castings of the core. Now the production situation is as follows. First, the hard-type casting precision and finish directly affected by the hardness of precision and finish, and therefore must ensure that hard type