Description of problems needing attention in valve installation

1. Placement location, height and deviation of revenue and expenditure outlet must meet the requirements of the plan, and the adjacency should be firm and precise.
2. All kinds of manual valves installed on the insulation pipeline shall not have downward handles.
3. Surface inspection must be carried out before valve placement. The nameplate of the valve should conform to the current national standard "General Valve Marking" GB 12220. For valves with pressure greater than 1.0 MPa and blocking function on backbone pipe, strength and precision performance tests should be conducted before placement, and the valves can be used quasi-qualified. In the strength test, the test pressure is 1.5 times of the nominal pressure, and the continuous time is not less than 5 minutes. The valve shell and packing should pass without leakage. In precision test, the test pressure is 1.1 times of the nominal pressure. The test pressure should meet the requirement of GB 50243 scale in the continuous time of test, and pass with no leakage on the valve sealing surface.
4. Handwheels, handles and transmission mechanisms are not allowed to be lifted and collisions are strictly prohibited.

5. Gate valves of belt drive mechanism shall be placed according to the delimitation of product utilization specification.