00/140907

Description:
The chemical resistance of rubber gaskets and compressed fibre gaskets can be considerably improved by inserting them into a PTFE-envelope. Because of the good adaptability of PTFE, particularly low sealing rates can be achieved with adequate gasket pressure.

By choosing particularly suitable styles of PTFE with low cold-flow (e.g. Dyneon TFM 1600),and by using special combinations of insert materials, e.g. corrugated metal rings with graphite cover on both sides, even the most demanding sealing problems (e.g. enamelled flanges or applications with serious thermal cycling) can be solved.

Applications:
PTFE-envelope gaskets are being widely used in the food and beverage industry, as well as in the pharmaceutical and chemical industry, because of their anti-adhesive properties and the physiological harmlessness of PTFE. They can be removed quickly and easily - and without residue - from the flange faces, new gaskets are installed in no time.

Material properties:
The envelope is made from 100% pure virginal PTFE.

By adding 2%of conductive pigment to the PTFE-resin, or by adding earth connection points to the corrugated metal ring, electrical conductivity can be assured.

For use with diffusing or strongly toxic media (e.g. chlorine gas), special PTFE-envelopes with 0,75mm thick material and reinforced inner diameter acting as diffusion barrier, can be produced.

Different styles:

Y-Envelope
Machined PTFE-envelope, normally with only one insert. For uncritical applications with low temperature and low pressure. Insert at customer´s option.

UR-Envelope
Machined PTFE-envelope for demanding applications. No notch-effect at inner diameter. These PTFE-envelopes can be fitted with various inserts or insert combinations. Larger diameters are produced in welded (folded tape) construction. A complex welding process - avoiding the problematic overlapping of the PTFE-material - makes the production of large PTFE-envelopes possible. Those have the same features and high quality standard as the smaller, machined, seamless versions.

UR-D-Envelope
Like style UR, but with additionally reinforced inner diameter as diffusion barrier. Inserts at customer´s option.

UE-Envelope
Machined PTFE-envelope for flanges according to DIN 2691 (tongue and groove)and DIN 2692 (male and female). Inserts at customer´s option.

UE-D-Envelope
Like style UE, but with additionally reinforced inner diameter as diffusion barrier. Inserts at customer´s option.

Please do not hesitate to contact us for any additional information you might need.

Since all properties, specifications and application parameters shown throughout this product information are approximate and may be mutually influenced, your specific application should not be undertaken without independent study and evaluation for suitability. All technical data and advice given is based on experiences TEADIT has made so far. Failure to select proper sealing products can result in damage and/or personal injury. Properties, specifications and application parameters are subject to change without notice.
TEADIT does not undertake liability of any kind whatsoever.