一、问题的提出近年来,60t敞车上心盘裂纹问题日趋严重,尤其是新造的C_(62A)型敞车出厂后不到一个厂修期就大量产生裂纹。经济上造成很大损失,并使得本已紧张的厂段修能力更为紧张。1984年,四方车辆研究所与部分工厂联合调查了上心盘裂纹的情况,在段修的C_(62A)型敞车中(这些车均未做过厂修),调 First, the issue put forward In recent years, 60t gondola core plate cracks become more serious problems, especially the new C_ (62A) gondola car factory less than a factory repairs a lot of cracks. Caused great economic losses and made the already tight factory repair capacity more tense. In 1984, Sifang Vehicle Research Institute and some factories jointly investigated the situation of the crack on the center plate. In the section of C_ (62A) gondola (none of these vehicles have been factory-repaired)