After finger-tightening the bolts so that the circumference of the inside bore of each flange snugly touches the gasket seal of the companion flange, make sure the valve is aligned before proceeding.

• 在手动紧固螺栓，使得每个法兰的镗孔内侧圆周贴紧配对法兰的密封垫片后，在继续安装前，要确认阀门已经对齐。