判断题
A.100mm B.110mm C.140mm D.180mm
A.GB/T228-2002 B.GB/T238-2002 C.GB/T238-1999 D.GB/T228-1987
A.电弧焊接头 B.锥螺纹接头 C.直螺纹接头 D.套筒挤压接头
A.越低B.越高C.不变D.二者无关
A.12mm B.14mm C.16mm D.18mm