Should I use asbestos or non-asbestos jointing sheet?
For almost every new order, specify non-asbestos jointing sheet. Asbestos is a recognised health hazard and is banned or restricted in many countries. Modern compressed non-asbestos fibre (CNAF) sheet covers most steam, water, oil and chemical duties when the right grade is chosen for the temperature and pressure. Use asbestos sheet only where it is still legal and specifically required.
| Compressed asbestos fibre (CAF) | Compressed non-asbestos fibre (CNAF) | |
|---|---|---|
| Fibre | Asbestos | Aramid, glass or other fibres with a rubber binder |
| Health and regulation | Hazardous; banned or restricted in many countries | No asbestos hazard |
| Service range | Historically wide | Wide, but depends on the grade; check the data sheet for temperature and pressure |
| Typical choice today | Legacy and replacement only, where legal | Standard choice for new gaskets |
How to specify jointing sheet
Give the fluid, the maximum temperature and pressure, the flange standard and size, and the sheet thickness (1.5 mm and 3 mm are common). The grade is then chosen so its rated limits cover your duty with a margin.
Cutting gaskets
Jointing sheet is supplied as sheets and cut into ring or full-face gaskets to your flange drawing.