Causes of flange leakage

What is the cause of flange leakage?

1. Reason for flange leakage: wrong mouth

The staggered seam means that the pipe and the flange are vertical, but the two flanges are not concentric, and flanges are not concentric, so the surrounding bolts cannot freely penetrate the bolt holes.

There is no other way, only reaming or small bolts are screwed into the bolt holes, which will reduce the tension of the two flanges, and the sealing surface of the sealing surface is also deviated, which is very easy to leak.

2. Reasons for flange leakage: Corrosion effects

Because the gasket is corroded by the corrosive medium for a long time, the gasket undergoes chemical changes, the corrosive medium penetrates into the gasket, the gasket begins to soften, loses compressive force, and causes flange leakage.

3. Reasons for flange leakage: partial mouth

Eccentricity means that the pipeline and the flange are not perpendicular, not concentric, and the surface of the flange is not parallel. When the internal medium pressure exceeds the load pressure of the gasket, flange leakage will occur. This situation is mainly caused by installation or maintenance, and it is relatively easy to find. As long as the actual inspection is completed, the accident can be avoided.

4. Reason for flange leakage: Opening

The opening is because the flange gap is too large. When the flange clearance is too large, causing external load (such as axial load or bending load), the gasket will be impacted or vibrated, lose the pressing force, and gradually lose the kinetic energy of the seal, resulting in failure.

5. Reasons for flange leakage: pressure

When installing flanges, it is standard for two flanges to be butted together. However, in the system production, the temperature of the pipeline will change after entering the medium, which will cause the pipeline to expand or deform, so that the flange is subjected to bending load or shear force, which may easily lead to the failure of the gasket.

6. Reason for flange leakage: wrong hole

The wrong hole means that the pipe and the flange are concentric, but the distance between the two bolts is greater than the bolt hole. The wrong hole will cause stress to the bolt, and the force cannot be eliminated, which will produce a shear force on the bolt, and the bolt will break for a long time, resulting in seal failure.

7. Reasons for flange leakage: thermal expansion and contraction

Due to the thermal expansion and contraction of the fluid medium, and the expansion or contraction of the bolt, the gasket will have a gap, and the medium will leak through the pressure.