Gate valve shortcomings are as follows: Between the sealing surface easily lead to erosion and abrasion, maintenance more difficult. Large size, open the need for a certain space, open and close a long time. The structure is more complex. Zhaku types: According to the sealing surface configuration can be divided into wedge gate valve and parallel gate valve, wedge gate valve can be divided into: single gate, double gate and elastic gate type; gate gate type parallel gate Can be divided into single gate and double gate type. According to the thread position of the stem division, can be divided into Ming rod valve and dark rod gate valve two. Gate valve installation and maintenance should note the following: Hand wheel, handle and transmission are not allowed to lift, and no collision. Double gate valve should be installed vertically (ie stem in a vertical position, the hand wheel at the top). The gate valve with bypass valve should open the bypass valve before opening (to balance the pressure difference between inlet and outlet and reduce the opening force). Gate valve with transmission, according to the instructions of the product installation instructions. If the valve is always on and off, lubricate at least once a month.
elbow
Wpb Elbow,Lr Elbow,Welding Elbow
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