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永嘉渤工閥門有限公司
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Bohai Valve Co., Ltd. Yongjia
Contact: Mr. Wang
Phone 577 -57796661 / 057796662
Fax 577 -67367855
Phone: 13806833242
E-mail: 258193218@qq.com
Address: Industrial Zone Oubei Puxi
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Matters needing attention and key points of installation of American standard gate valve

更新時間:2018.07.20
Handwheel, handle and drive mechanism are not allowed to be hoisted, and collision is strictly prohibited. 2. Double gate gate valve shall be installed vertically (i.e. the stem is in the vertical position and the handwheel is at the top). 3. Gate valves with bypass valve should open bypass valve before opening (to balance pressure difference between inlet and outlet and reduce opening force). 4. The gate valve with drive mechanism shall be installed according to the specifications of the product operation manual. 5. If the valve is frequently switched on and off, lubricate at least once a month. 6. The installation position, height and inlet and outlet direction must meet the design requirements, and the connection should be firm and tight. 7. All kinds of manual valves installed on the insulated pipes shall not have downward handle. 8. The gate valve with drive mechanism shall be installed according to the provisions of the product operation manual. 9. Appearance inspection must be conducted before valve installation, and the valve nameplate should comply with the current national standard "general valve mark" GB12220. For valves with working pressure greater than 1.0mpa and with cut-off function on main stem pipe, strength and strict performance test should be conducted before installation. During the strength test, the test pressure is 1.5 times the nominal pressure, and the duration shall not be less than 5min. The valve housing and packing shall be qualified without leakage. During the strict test, the test pressure was 1.1 times of the nominal pressure. The test pressure shall meet the GB50243 standard for the duration of the test, and the valve disc sealing surface shall be qualified without leakage.
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