It’s one of the questions we’re asked most, and the honest answer is: it depends. Gasket life is set by the conditions the gasket works in, not by the calendar. Here’s what drives it and how to judge when replacement is due.
What shortens gasket life
- Temperature — every compound has a working range; running near the top of it ages the gasket faster.
- Media and cleaning chemicals — a compound that suits the process fluid may not suit the acid or caustic used to clean the unit.
- How often the pack is opened — each opening and re-tightening works the gasket.
- Over-tightening — compressing the pack beyond its specified dimension crushes gaskets.
- Pressure and temperature cycling — frequent starts, stops and swings fatigue the material.
Signs gaskets are at the end of their life
- Hard, brittle or cracked rubber
- Gaskets that stay flattened after the pack is opened
- Weeping at the edges of the pack
- Leaks that return after tightening
- Swelling or softening from chemical attack
Replace the pack, not one gasket
When gaskets are replaced, it is usually best to renew every gasket in the pack at the same time. Mixing old and new gaskets gives uneven compression, and the old gaskets tend to fail soon after.
Choosing the right compound
NBR, EPDM and Viton are common gasket materials, each with strengths and limits. The right one depends on both media, the operating temperature and your cleaning chemicals. If gaskets have been failing early, the compound may not suit the duty. See replacement gaskets.
Setting an interval
The best way to set a replacement interval is to inspect the gaskets at each service and record their condition. After a couple of cycles, you’ll have a realistic interval for that specific unit and duty.
Need gaskets or a regasketing service? Request a quote or call (02) 9897 7371.