Product List for PTFE Components
PTFE ENVELOPE GASKETS
PTFE envelope gaskets are still a commonly used method of sealing between flange faces in pipelines, distillation columns, reactor vessels, etc.
A PTFE envelope gasket incorporating an insert of compressible material, combines the chemical resistance of PTFE with the resilience of the selected insert. This combination provides a gasket that us capable of compensating for irregularities, which are often present in flanges, particularly those with a very large diameter.
Construction and size range
Type ‘M’ - The PTFE envelope is precision machined to produce a smooth snug-fitting bore to exactly the correct thickness for the insert.
Sizes: up to DN600 - ASA 24 inch bore.
Type ‘V’ - The envelope is knifed or sliced rather than machined, to produce a thinner, more economical gasket.
Sizes: up to DN600 - ASA 24”.
Type ‘W’ - The envelope is produced by forming PTFE tape around the gasket (insert) bore and then welding the ends. This type of construction can be used to produce oval gaskets.
Sizes: Any size over 450mm (18”) inside diameter.
Standard Flanges - Beldam Crossley envelope gaskets can be produced to match all standard flanges, normally fitting inside the bolt circle. Full face gaskets can also be supplied.
Non-standard gaskets - Customised and special gaskets such as reversed envelopes can be supplied to specification.
Insert Materials
- Compressed fiber jointing
- Rubber
- Fluoro-elastomers
- Stainless steel corrugated rings, with or without tabs
- Temperature range: - 240°C to +250°C depending on the type of insert material used.
To download PDFs of our various product ranges,
please visit the relevant sections above.
