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Installation of forged steel gate valves

2022年01月13日

Instructions for the installation and use of forged steel gate valves: 1. For various manual valves installed on insulated pipelines, the handle should not be downward. 2. The installation position, height, and direction of inlet and outlet must meet the design requirements, and the connection should be firm and tight. 3. Before installing the valve, a visual inspection must be conducted, and the nameplate of the valve should comply with the current national standard "General Valve Markings" GB12220. For valves with a working pressure greater than 1.0MPa and a cutting effect on the main pipe, strength and tightness tests should be conducted before installation, and they can only be used after passing the test. During the strength test, the test pressure is 1.5 times the nominal pressure


1. The handles of various manual valves installed on insulated pipelines shall not be downward.


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


3. Before installing the valve, a visual inspection must be conducted, and the nameplate of the valve should comply with the current national standard "General Valve Markings" GB12220.


For valves with a working pressure greater than 1.0MPa and a cutting effect on the main pipe, strength and tightness tests should be conducted before installation, and they can only be used after passing the test. During the strength test, the test pressure shall be 1.5 times the nominal pressure, and the duration shall not be less than 5 minutes. The valve shell and packing shall be deemed qualified if there is no leakage. During the tightness test, the test pressure shall be 1.1 times the nominal pressure; The test pressure should meet the requirements of GB50243 standard during the duration of the test, and it is qualified if there is no leakage on the sealing surface of the valve disc.