Home Company Products Contacts Site map

products

James Walker® Gaskets & Jointings > PTFE gaskets



  PTFE gaskets
Fluolion® Envelope Gaskets
 
DESCRIPTIONS
Aresilient fibre material encased in a thin cover of PTFE. The resulting gasket combines the inertness of virgin PTFE with the mechanical properties of the compressed fibre sheet. James Walker supplies three envelope designs: Fin Type; Machined Square Type; Folded Tape Type.

TYPICAL APPLICATIONS
Flanged joints handling highly aggressive fluid media that would 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 noncontamination are essential.
 
FIN TYPE
• Standard design: most economical envelope gasket.
• Suits majority of applications where highly abrasive media 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 300mm.
• Can be adapted to non-circular planforms.
 
MATERIALS
Cover: virgin Fluolion PTFE. Inserts: compressed non-asbestos fibre, synthetic rubber-proofed woven cloth, and laminated combinations of these.
 
SERVICE CAPABILITY
Maximum temperature Typically +260°C for PTFE (which is usually lower than insert material)
Minimum temperature –80°C
Maximum pressure Typically 64bar
 
HOW SUPPLIED
Custom made to suit all standard flanges and non-standard shapes.