金刚镗床镗削属于精密加工,其镗孔精度可达(),表面粗糙度值小Ra0.6m。 ["H4","H5","H6","H7"]
UM71型无绝缘轨道电路接收器的主要作用有检查报警信号、调整轨道电路。
ZPW-2000A无绝缘移频自动闭塞系统正线检测盘的型号是() ["ZPW•ZXJ","ZPW•PJZ","ZPW•JZ","ZPW•PJC"]
随着厚度的增加,钢材的()强度设计值是下降的。 ["抗拉","抗拉和抗压","抗拉、抗压和抗弯","抗拉、抗压、抗弯和抗剪"]
分动外锁闭提速道岔动作时,应()。 ["斥离轨先动","密贴轨先动","斥离轨密贴轨同时动","密贴轨待解锁后再动"]
当满足哪些条件时GYK文件应产生一条记录?