单项选择题
A.角接接头 B.对接接头 C.搭接接头 D.T型接头
A.高碳钢 B.淬硬钢 C.碳当量Ce>0.6% D.15MnV和15MnTi
A.+2,-2mm B.+3,-2mm C.+4,-2mm D.+6,-2mm
A.300m B.350m C.400m D.450m
微信扫一扫,加关注免费搜题