1. The sealing gasket and flange sealing surface should be cleaned thoroughly, and there should be no scratches, spots or other defects that affect the sealing performance of the connection.
2. The outer diameter of the sealing gasket should be smaller than the outer diameter of the flange sealing surface, and the inner diameter of the sealing gasket should be slightly larger than the inner diameter of the pipeline. The difference between the two inner diameters is generally taken as twice the thickness of the sealing gasket to ensure that the inner edge of the sealing gasket does not protrude into the container or pipeline after compression, so as not to hinder the flow of fluid in the container or pipeline.
3. The pre tightening force of the sealing gasket should not exceed the design specifications to avoid excessive compression and loss of rebound ability of the sealing gasket.
4. When compressing the sealing gasket, try to use a torque wrench as much as possible. For large bolts and high-strength bolts, hydraulic tensioners should be used as much as possible. The tightening torque should be calculated based on the given sealing gasket compression, and the oil pressure of the hydraulic tensioner should also be determined through calculation.
5. When installing the sealing gasket, the nuts should be tightened in sequence. But it should not be tightened once to reach the design value. Generally, it should be cycled at least 2-3 times to ensure uniform stress distribution of the sealing gasket.
6. For pressure vessels and pipelines with flammable and explosive media, safety tools should be used when replacing sealing gaskets to avoid sparks caused by tool contact with flanges or bolts, leading to fire or explosion accidents.
7. If there is a leak in the pipeline, it must be depressurized before replacing or adjusting the installation of sealing gaskets. It is strictly prohibited to operate under pressure.