| ETHYLENE
PROPYLENE (EPDM) -30 degrees to +300 degrees F |
| The
most popular general purpose material. Excellent chemical
resistance to a wide variety of corrosive elements including
acids, caustics and hot water. It is abrasion resistant and
good for high temperature service. EPDM has poor oil resistance.
It is also satisfactory for intermittent steam sterilization. |
|
| NEOPRENE
(CR) -20 degrees to +200 degrees F |
| A good
choice for general purpose chemical resistance where
the media contains entrained oils. It also resists aldehydes,
certain alcohols, fertilizers, explosives, petroleum,
air, acids, alkalies and is abrasion resistant. |
|
| SOFT
NATURAL RUBBER (NR)
-30 degrees to +180 degrees F |
| The
most abrasion resistant diaphragm. Good in either wet or dry
abrasive service, water, some acids and alkalines. |
|
| HYPALON
(CSM)
0 degrees to +225 degrees F |
| Has
good resistance to strong oxidizing agents including
sulfuric acid. General chemical resistance is similar
to neoprene but with only moderate oil resistance. Also good
in certain chlorine service, for alkalies and is abrasion
resistant. |
|
| VITON
(FKM)
-20 degrees to +325 degrees F |
| Offers
exceptional resistance to oils, most chemicals and many solvents
at elevated temperatures. It can be used in most applications
involving mineral acids, salt solutions and chlorinated hydrocarbons..
Viton is not recommended for ammonia, its derivatives or polar
solvents, E.G. Acetone. Very costly, but sometimes works where
others fail. |
|
| TEFLON
TFE/EPDM
-30 degrees to +300 degrees F |
| TFE
is simply the most chemical resistant of all the diaphragm
materials. It is good for handling strong acids, alkalies
(caustics) and solvents. Because of its greater stiffness,
it significantly increases required closing/sealing forces
and on automatic valves may require a larger size actuator. |
|
| BUTYL
-20 degrees to +250 degrees F |
| A good
choice for gases because it has very low vapor and gas permeability.
Also good for many acids and alkalies. Good for applications
involving steam sterilization. |
|
|
