Installation and operation method

1. The flanges of valves and piping should be free of damage, scratches, etc., and kept clean. Especially when using metal washers (oval or octagonal cross-sections), the notches and washers of the flanges should be matched. Red tin should be coated and tested to ensure good sealing.

2. The verticality of the flange surface on the piping and the center line of the piping and the error of the flange bolt holes shall be within the allowable value range. After the valve and pipe center line are consistent, install it again.

3. When connecting the two flanges, the flange sealing surface and the gasket must be pressed evenly first, which ensures that the flanges are connected by the same bolt stress.

4. When tightening the bolt, use a wrench that matches the nut. When using oil pressure or pneumatic tools to tighten, be careful not to exceed the specified torque.

5, flange fastening to avoid uneven force, should be in accordance with the order of symmetry, cross-sense tightening.

6. After the installation of the flange, make sure that all bolts and nuts are solid and uniform.

7. The material of bolts and nuts must comply with regulations. After tightening, the bolt head should be exposed from the nut with two pitches.

8. To tighten the bolts and spirals, use washers to prevent vibration from loosening. In order to avoid adhesion between threads at high temperatures, the threaded part should be coated with an antiblocking agent (molybdenum disulfide) during installation.

9, for high temperature valves above 300 degrees Celsius, after the temperature rises, must tighten the flange bolts, valve cover fastening bolts, pressure sealing bolts and packing pressure cover bolts.

10, low temperature valve is installed at atmospheric temperature. In practical applications, when the medium passes through, it becomes a low-temperature state. Due to the formation of a temperature difference, flanges, gaskets, bolts, and nuts are shrunk. Since the materials of these parts are not the same, their respective linear expansion coefficients are also different. Very easy to leak environmental conditions. In view of this objective situation, when tightening the bolts at atmospheric temperature, it is necessary to use moments that take into account the shrinkage factors of the parts at low temperatures.