Home > Resist-o-Seal®


A self-endergized, PTFE faced gasket


The Resist-O-Seal® gasket is a PTFE faced gasket with an elastomer injected between the faces and bonded to them. Concentric sealing corrugations are molded into the PTFE and filled from behind by the elastomer, enabling the gasket to seal at very low torques with the sealing energy supplied as the elastomer is compressed.


Gone are the common failure modes with conventional PTFE gaskets fluttering, distortion over time, and tearing. Support provided by the bonded elastomer backing simply prevents their occurrence.


Features and Benefits of the HMS RESIST-O-SEAL®

  • Superior sealing at low bolt loads
  • Molded sealing rings provide the best seal
  • Eliminates the need for standard envelope gaskets
  • Sizes 1 / 2 ” - 24” 150# class full face
  • Standard construction EPDM with PTFE 60 durometer


Available in alternate materials

  • EPDM (solid) 60 durometer
  • Fluorelastomer - (Solid) 60 durometer
  • EPDM with PTFE envelope 75 durometer


May be used with all flange types

  • All corrosion resistant thermoplastic
  • Polyvinyl Chloride (PVC)
  • Chlorinated Polyvinyl Chloride (CPVC)
  • Polypropylene
  • Fiberglass reinforced plastics (FRP)
  • Polyvinylidene fluoride - Kynar® (PVDF)
  • All metal (iron, steel, stainless steel)


For glass-lined and stainless piping
The Resist-O-Seal gasket is designed for glass lined, PVC, fiberglass and polypropylene piping systems where PTFE is the preferred gasket material for corrosion resistance.


Fragility aside, the durable and inert Resist-O-Seal gasket is also ideal for stainless steel piping in the food and petrochemical industries.


Since very low bolt torque will affect a seal, the chance of damaging a fragile glass or plastic flange is greatly reduced when a Resist-O-Seal gasket is used. The gasket can tolerate some degree of misalignment when used in expansion joint flanges.


Standard elastomer backing includes Nitrile, Chloroprene, Fluoroelastomer, Silicone, EPDM and Aflas. Gaskets are produced for up to 24 in. pipe. Nominal temperature limits are determined by the elastomer.


Please contact us for information on other elastomers and larger gaskets and for the name of your nearest HMS distributor.


Common Industries:
Chemical Processing, Mining, Offshore Drilling Rigs, Pulp & Paper, Semiconductor and many others


Common Chemical Applications:
Acids - Hydrochloric, Sulfuric
Caustics - Sodium Hydroxide, Potassium Hydroxide, Calcium Hydroxide
Water - De-ionized, Potable
Other - Hydrocarbons, Chlorine Services


The Resist-O-Seal® gasket is a PTFE faced gasket with an elastomer injected between the faces and bonded to them.