... DN50 - DN350 2) Material: disc nylon coated Valves These products are widely used in water source projects ... , petrochemical, heat supply,shipbuilding, medicine and metallurgy industries. Valves used for regulating orcutting off liquids in pipelines.Liquids available ... , sea water, air, foodstuff and oil. DN50- 300 valves are suitable for gear operators, and electric and pneumatic controlactuators. ...