A.对口焊接 B.承插焊接 C.渗透焊接 D.击穿焊接
A.10mm B.20mm C.30mm D.40mm
A.报警阀阀体底边距室内地面高度为1.2m B.侧边与墙的距离不小于0.5m C.正面与墙的距离不小于0.5m D.报警阀组凸出部位之间的距离不小于0.5m
A.25 B.20 C.15 D.10
A.泄水阀 B.过滤器 C.排气阀 D.试水阀