Encapsulated O-Rings and Custom O-Rings | Has-Mor Industries
Home Home
Has-Mor IndustriesHas-Mor Industries
Has-Mor Industries
Has-Mor Industries
P.O. Box 111
Dunmore, PA 18512 U.S.A.
Tel: 570-383-0185
Fax: 570-489-3560

Product Information

To download a PDF version of these pages click  here

General Info | Materials | Sizes | Custom Shapes | Installation & Service Life

Has-Mor’s main product offering is FEP and PFA encapsulated o-rings. Encapsulated o-rings are double-action sealing elements. The seal is provided by the FEP or PFA encapsulation; whereas, the elastomer o-ring (fluorocarbon rubber, silicone, etc.), serves as an elastic pretension element exerting a permanent and uniform pressure against the mating surface. The FEP or PFA “jacket” encases the elastomer o-ring without seams.

Encapsulated o-rings are used wherever conventional elastomer o-rings cannot be used due to their inadequate chemical resistance. FEP and PFA materials offer superior chemical resistance to a greater range of media, but offer no rubber elastic properties, by combining the FEP or PFA jacket with such core materials, the o-ring now offers the required elasticity and chemical resistance expanding uses into the chemical industry, medical technology, petrochemical, food industries and similar industrial uses.

Encapsulated o-rings are primarily used as static seals (axial and radial) for lids and covers, flanges, disks, etc. When subject to significant strains and stresses (speed and pressure), the seal can also be used for dynamic sealing for pistons, rods, valve spindles, and mechanical seals. When greater stress is anticipated, preliminary experiments are recommended.

The most important advantages of o-rings with FEP or PFA encapsulation as compared to conventional o-rings include:

  • low friction, no stick slip effect, no adhesion tendency
  • very good chemical resistance, compatible with most fluids and chemicals
  • no contamination when used with food, pharmaceutical and medical products
  • physiologically harmless, can be sterilized
  • low steam permeability
  • wide temperature ranges (varies based on o-ring compound)


Teflon® is a registered Trademark of DuPont.

PayPal Acceptance Mark
Has-Mor Industries
Has-Mor Industries
Has-Mor Industries

© 2007 Has-Mor Industries. All Rights Reserved.
Website Managed
by Leigh Morgan

Home Contact Information