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.

Recommendations:

• 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:

1. Molybdenum Disulphide
2. Copper
3. PTFE

• 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.