Do you know all these things about flanges? Let's follow the editor of Cheapest Spectacle Blind Flange to have a simple understanding!
1. The flange surface on the pipeline should be perpendicular to the center line of the pipeline, and the position error between the flange bolts and the center of the pipeline should be within the allowable range. Before installation, the centerline of the valve and the pipeline should be the same.
2. The flange surfaces of valves and pipelines should be free from damage, scratches, etc., and kept clean, especially when metal gaskets are used, the grooves of the flanges and gaskets are consistent to ensure a good sealing state.
3. The tightening of flanges should avoid uneven force, and should be tightened evenly and orderly according to the symmetrical direction and the cross direction.
4. When tightening the bolts, please use a plate that matches the nut. When using hydraulic and pneumatic tools to pre-tighten the star wheel, do not exceed the specified operating distance.

5. When connecting two flanges, make sure that the flange sealing surface and gasket are evenly compressed to ensure that the flanges are connected under the same bolt stress.
6. After the flange is installed, make sure that all bolts and nuts are evenly tightened.
7. For the fastening of bolts and nuts, in order to prevent vibration caused by loosening, washers should be used. In order to avoid adhesion of threaded joints under high temperature, the threaded parts of the installation should be coated with anti-sticking agent.
8. For high temperature valves above 300 degrees, after the temperature rises, it is necessary to tighten the flange connection bolts, bonnet fastening bolts, pressure seals and packing seal bolts again.
9. The cryogenic valve is installed at room temperature. Due to the formation of temperature differences, flanges, washers, bolts and nuts will shrink. Due to the different materials of these parts, their linear expansion coefficients are also different, which creates an environmental condition that is very easy to leak. From this objective situation, when tightening bolts at room temperature, it is necessary to adopt the following method: Consider the shrinkage coefficient torque of each component at low temperature.
The above is the editor of Cheapest Spectacle Blind Flange: What you need to know about these matters about flanges.