| Material:
1) Viton
2) Silicone / FEP
3) PTFE
4) Urethane
5) Silicone
6) Fluorosilicone
7) Buna nitrile
8) Split PTFE / backup
9) Solid PTFE / backup
10) Neoprene
11) EPDM
12) Viton / FEP
13) Nitrile ethylene-propylene
EP, En or EPDM ethylene-propylene (EPDM) compounds are prepared from ethylene and propylene and usually a third monomer. These compounds are used frequently to seal phosphate ester fire resistant hydraulic fluids such as skydrol. They are also very effective in brake systems, and for sealing hot water and steam. Ethylene-propylene compounds have good resistance to mild acids, alkalis, silicone oils and greases, ketones, and alcohols. They are not recommended for petroleum oils or diester lubricants.
Ethylene-propylene has a temperature range of -67oF to 302oF (-55oC to 150oC). It is compatible with polar fluids that adversely affect other elastomers. It has such advantages as excellent weather resistance, good low temperature flexibility, excellent chemical resistance, and good heat resistance. But it has poor petroleum oil and solvent resistance. Nitrite, Buna N, or NBR nitrite is the most widely used elastomer in the seal industry. The popularity of nitrite is due to its excellent resistance to petroleum products and its ability to be compounded for service over a temperature range of 67oF to 257oF (-55oC to 120oC). Nitrite is a copolymer of butadiene and acrylonitrile. |
