What are the causes of flange leakage?

This week, we received a complaint from a customer about another supplier. The flange we bought from another supplier was leaked. We would like to ask for our inquiry and purchase again.

Today, let’s take a look at the causes of flange leakage

1.Wrong mouth, refers to the pipe and flange are perpendicular, but the two flanges have different centers. The flange has different centers, so the bolts around it cannot penetrate the bolt holes freely. In the absence of other methods, only reaming or using a smaller size of the bolt through the bolt hole, and this method will reduce the tension of the two flanges. In addition, the sealing surface of the sealing surface line is also deviated, which is very easy to leak.

Weld neck flange WN flange A182 Gr F321 RTJ ASME B16.5

Weld neck flange WN flange A182 Gr F321 RTJ ASME B16.5

2.Open mouth, refers to the flange clearance is too large. When the clearance of the flange is too large and the external load is caused, such as axial or bending load, the gasket will be impacted or vibrated and lose the compression force, thus gradually losing the sealing kinetic energy and leading to failure.

3.Staggered hole means that the pipe and flange are concentric, but the distance between the bolt holes relative to the two flanges is large. The wrong hole will cause the bolt to produce stress, the force is not eliminated, will cause shear force on the bolt, the bolt will be cut off for a long time, resulting in sealing failure.

4.Stress influence, in the installation of the flange, the two flanges are more standard butt, but in the system production, after the pipeline into the medium, resulting in pipe temperature change, so that the pipeline expansion or deformation, so that the flange is subjected to bending load or shear force, easy to cause gasket failure.

5.Corrosion effect, because the corrosive medium on the gasket for a long time, so that the gasket chemical change. The corrosive medium penetrates into the gasket, and the gasket begins to soften and lose compression, resulting in flange leakage.

6.Thermal expansion and cold contraction. Due to the thermal expansion and cold contraction of the fluid medium, the bolts expand or contract, so that the gasket will produce a gap and the medium will leak through the pressure.

Our company’s quality is very good, there will be no leakage. If you need, please contact me. Email:sales@haihaogroup.com