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Installation of big size valve

Time:2019-03-09
Big Size valve installation essentials
1. The installation location, height and direction of the inlet and outlet must meet the design requirements, and the connection should be firm and tight.

Big size valve installation essentials

1. The installation location, height and direction of the inlet and outlet must meet the design requirements, and the connection should be firm and tight.

2. For all kinds of manual valves installed on the insulation pipe, the handle shall not be downward.

3, the valve must be installed before the appearance of inspection, the valve nameplate should comply with the current national standard "general valve marks" GB 12220 provisions.For valves whose working pressure is greater than 1.0mpa and which have the function of cutting off on the main pipe, strength and tightness test shall be conducted before installation, and they shall be used only after passing the test.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 without leakage.During the tightness test, the test pressure is 1.1 times of the nominal pressure;The duration of the test pressure during the test shall meet the requirements of GB 50243 and shall be qualified if there is no leakage on the disc sealing surface.