Flanged joint leaks occur when fluid carried in the pipe leaks around the gasket or face of the flange. These leaks can cause significant damage, environmental problems, physical harm to personnel located in the work area and generate loss of time due to downtime, which makes your operation less efficient.
As experts in sealing solutions, Flexilatina de Colombia provides technical advice to offer the best alternative that adapts to the operating conditions of each type of industry. The best way to prevent leaks in flanged joints is to choose the correct gasket according to the application for which it is required and by following good installation practices in the flanged joint.
When leaks occur at flanged joints, the first thing to identify is the root problem, which is often caused by incorrect component materials, improper dimensions, or incorrect installation procedures.
There may be other possible causes as shown below:
- Gasket with corrosion.
Significant gasket corrosion is a common cause of flange leaks and is due to poor gasket material selection. To solve this problem, the damaged gasket must be replaced with a new one, taking into account that it adjusts to the different operating conditions (pressure, fluid and temperature), in addition, it must be correctly installed, guaranteeing that the torque applied to the bolts and nuts is adequate.
- Packaging is over-extruded
If you notice that your gasket is excessively extruded, your flange leak may be the result of cold flow, insufficient load capacity of the gasket, or too much holding load of the fasteners. To solve this problem, select a gasket with a premium fill material that inhibits cold flow, such as PTFE foil gaskets.
- 3. The packaging is very crushed
When the gasket is very crushed, it is because bad practice was carried out when installing it, since a torque greater than that required for said gasket was applied. To mitigate these failures, it is necessary to verify that the applied torque is adequate, or in this case choose a gasket that supports a greater compression load.
- The gasket protrudes from the flanges
If a gasket is mechanically damaged and protrudes from the flanges, it is likely that the leak was caused by an incorrect size of gasket or that it was not centered correctly at the time of installation. To mitigate this type of inconvenience, it must be ensured that the measurements of the packaging are adequate and match the flanges on which it will be installed.
- Proper compression was not achieved in the packaging
If the leak presented is due to the lack of compression of the gasket, it must be verified that the applied torque is optimal, and if necessary, choose a new gasket that is more compressible with a low torque.
- Pack thinner on the outside diameter than on the inside diameter.
If your gasket is substantially thinner on the outside diameter (OD) compared to the inside diameter (ID), this indicates excessive rotation or flexing of the flange caused by bolt overload. To remedy this, you can modify the gasket dimensions to move the gasket reaction closer to the bolts, which minimizes bending movement. You can also provide additional rigidity to the flange by adding backer rings. Finally, you can reduce the required seating stress by selecting a gasket with a lower sealing load requirement, such as a nonmetallic gasket made of a softer material.
- The packaging is not evenly compressed
If the gasket is compressed unevenly, or if its thickness varies periodically around its circumference, it can lead to leaks. This may be due to inadequate assembly of the flanged joint, which is why to mitigate these inconveniences, the guidelines of the ASME PCC-1 standard must be followed, which indicates how the correct installation should be carried out, guaranteeing that all the bolts have the same load and that the flanges are parallel, aligned and properly spaced, guaranteeing a uniform torque throughout the packaging.
- Wide temperature variations
Wide temperature variations in your application environment can cause flange leaks. To solve this, you should choose a packaging that offers better loading with wide temperature variations, such as mica or flexible graphite.
If the correct packaging material is chosen, with the appropriate internal and external dimensions and a correct installation is carried out, the current leaks that occur can be repaired, additionally leaks in flanged joints will be greatly mitigated in the future, which will represent a safe line of work free of dangers and costs caused by leaks. We have the ideal technical staff, who will advise you on choosing the optimal packaging for the production process of each industry.