PTFE Envelope Gasket

PTFE Envelope Gasket - Style 9015

A PTFE envelope gasket is a composed gasket, it consists of an envelope of PTFE with an inlay such as non-asbestos fiber gasket, graphite, rubber and asbestos. The PTFE envelope gasket is mainly applied as a flange gasket in applications where a high chemical and high pressure resistance is required.

The Types of PTFE Envelope Gaskets

Slit Cut V Type PTFE Envelope Gasket

Slit cut PTFE 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 PTFE Envelope Gasket

Square Type PTFE envelope gasket provides continuity with pipeline bore for smooth flow and it is recommended where flange sealing width is restricted or thick inserts are used. Supplied with serrated surface.

Folded U Type PTFE Envelope Gasket

U Type PTFE envelope gasket has smooth surface finish - tape of PTFE is folded and joined by welding. and it is used for diameters over 300 mm. Can be adapted to non-circular planforms

Properties of a PTFE envelope gasket

PTFE envelope gaskets combine the benefits of different materials, it has the excellent resistance of ptfe to almost all chemicals, it can be used in wide temperature range. Good pressure resistance, depending on the choice of the core material. PTFE envelope gasket has good anti-adhesive surface, UV and ageing resistant, excellent dielectric properties, long term stable compression and recovery characteristics, low permeability towards gases and liquids, excellent non-stick characteristics.

PTFE Envelope Gasket Applications

PTFE envelope gasket is used in food sector and pharmaceutical industries, pipeline flanges, device and container flanges. It is also used in Glass lined pipe systems, distillation columns and reactor vessels where non-contamination is essential. PTFE envelope gasket is also suitable for chemical aggressive environment, which is hazardous for health, so it has wide range of applications mostly in the chemical and petro-chemical sector.

PTFE Envelope Gasket Specifications

Size : 25 NB to 300 NB
Outer body : ASTM A 395 Gr 60-40-18
Flange Connection : ANSI B 16.5
Face to Face : ANSI B 16.10
Spark Test : 15 KVA
Hydro Test : at 29.8 kg/cm2
Max Temp : 200°C