Gaskets and Sheet Jointings
Fluolion Envelope Gaskets
A resilient material encased in a thin cover of PTFE. The resulting gasket combines the inertness of virgin PTFE with the mechanical properties of the insert material.
James Walker supplies three envelope designs...
- Fin Type
- Machined Square Type
- Folded Tape Type
Flanged joints handling highly aggressive fluid media that would otherwise swiftly destroy the integrity of other materials. Often used with soft insert material on glass-lined pipework systems. Also used in food processing, where cleanliness and non-contamination are essential.
- Standard design: most economical envelope gasket.
- Suits majority of applications where highly abrasive madia are not used and turbulent flow will not create problems.
- Needs clearance between insert and envelope inside diameter to enable insert to be fitted.
Machined Square Type
- Provides continuity with pipeline bore for smooth flow.
- Recommended where flange sealing width is restricted or thick inserts are used.
- Supplied with serrated surface.
Folded Tape Type
- Has smooth surface finish - tape of PTFE is folded and joined by welding.
- Used for diameters over 300 mm.
- Can be adapted to non-circular planforms.
- Covers: virgin Fluolion PTFE.
- Inserts: compressed non-asbestos fibre, synthetic rubber-proofed woven cloth, and lamninated combinations of these.
Maximum temperature: typically +260°C for PTFE envelope, but also dependent on filler material.
How it is supplied
Custom made to suit all standard flanges and and non-standard shapes.