1 When flanges are integral with fittings or valves, holes for bolts are drilled to straddle the center line.
1 When flanges are integral with fittings or valves, holes for bolts are drilled to straddle the center line.
1如果法兰与连接件或阀门构成一个整体，则螺栓孔钻在圆心线两侧。