Gasket Fitting Guide
We recommend the following best practices to ensure correct gasket fitting:
- Care in material selection.
- Care of flange faces.
- Do not use jointing compounds.
- Gasket sealant or not? (Generally no gasket sealant is required). See here for more information on gasket sealants.
- Re-torque after 24 hours or one process cycle.
- Choose as thin a material as possible.
- Clean the flange faces and remove any dirt on the studs / bolts /nuts.
- Lubricate the threads and the nut face. If possible use a lubricant based on:
- Molybdenum Disulphide
- Before assembly ensure that the nuts run freely on the threads.
- Carefully fit the gasket taking care not to damage the gasket surface.
- Tighten the bolts in the recommended sequence (eg diametrically opposite) to about half load.
- Check visually that the flanges are uniformly loading the gasket.
- Tighten to the recommended torque for the flange system.
- After 24 hours of operation, or one process cycle, re-tighten to the correct torque (the gasket will have relaxed).
- If the flange has not been in service and is unlikely to be so in the short term then still re-tighten.
Use of Graphic & other Anti-Stick Coatings:
- Care should be taken to apply a very thin coating.
- Not recommended where flanges are worn or where high pressures (in excess of 17 bar) are expected.
- Do not use graphite grease.