我厂每年都要生产一批58型焦炉炉门上的紧丝座(图1)。以往都采用自由锻成型、材料消耗大,加工工时多,因而成本高。后来我们采用无飞边胎模锻降低了材料消耗(单件省料18.5公斤)和机加工工时(单件省工时4小时),单件成本降低35元。图2为锻件图。在设计热锻件时,热膨胀系数取 Each year I plant to produce a number of 58 coke oven door tight seat (Figure 1). In the past are free forging molding, material consumption, processing time and more, and therefore high cost. Later, we use non-flying tire die forging to reduce the material consumption (18.5 kg of material saved in one piece) and machining working hours (4 hours of single-time working hours), reducing the cost of a single piece by 35 yuan. Figure 2 forgings. In the design of hot forging, the coefficient of thermal expansion