Seal for thermowave heat exchanger, model TL90.

Material design:
NBR  Acrylonitrate-butadiene rubber. Operating temperature range from -40oC to + 140oC (depends on modification). It is used mainly for water, liquids based on mineral oils, animal and vegetable fats, hydrocarbons, ammonia.
EPDM  Ethylene-propylene-diene-modified rubber. Operating temperature range from -30oC to + 180oC (depends on modification). It is used mainly for water, steam, alcohol, ketones, washing liquids, organic and inorganic acids and alkalis.
CR Chlorine-butadiene rubber. Operating temperature range from -45oC to + 130oC (depends on modification). It is used mainly for ammonia, freons, carbon dioxide, silicone oils, solvents, water, glycols and basic refrigerants.