Key points for installation of large diameter gate valve

Key points for installation of large diameter gate valve:

1. The installation position, height, inlet and outlet direction shall meet the design requirements, and the connection shall be firm and tight.

2. The handle of all kinds of manual valves installed on the thermal insulation pipeline shall not be downward.

3. Visual inspection shall be carried out before valve installation, and the nameplate of the valve shall comply with the provisions of the current national standard General Valve Marking GB 12220. For valves with a working pressure greater than 1.0 MPa and a cutoff function on the main pipe, strength and tightness tests shall be conducted before installation, and they can be used only after they are qualified. During the strength test, the test pressure shall be 1.5 times of the nominal pressure, and the duration shall not be less than 5min. The valve shell and packing shall be qualified if there is no leakage. During the tightness test, the test pressure shall be 1.1 times of the nominal pressure; The duration of the test pressure shall meet the requirements of GB 50243 standard, and it is qualified if there is no leakage on the sealing surface of the ram.