Non-Return Valve 70 / 70U

Non-return valve for the prevention of unintended gas mixtures, for flow rates up to 1120 m³/h (air), up to 16 bar, for use in thermal processing, certified to EN 746-2

safety element: non-return valve [NV]
every non-return valve 100% tested
DIN EN ISO 5175-2
protects against flashbacks, for fuel gas-compressed air-mixtures
ultra-low opening pressures (approx. 4 mbar), ultra-low pressure drop
62 X 137 X 160 mm, 1.255-1.679 g

Information

WITT non-return valves for reliable protection against dangerous reverse gas flow. Every non-return valve 100% tested.

Benefits:

a spring-loaded non-return valve prevents a reverse flow of gases which could lead to unwanted gas mixtures
low pressure drops – using complex valve assembly with low opening pressures (approx. 4 mbar)
brass filter protects the non-return valve against flashbacks, extending the service life
diverse applications – useful for many technical gases
reduce installation costs – the spring-loaded valve is not affected by gravity and may be installed in any orientation

Operation / Usage:

non-return valves are used to protect equipment and pipelines against dangerous reverse gas flow. Use is possible for applications in accordance with EN 746-2
non-return valves are proved in accordance with DIN EN ISO 5175-2. They may also be used as a safety device to protect against flashbacks (proved in accordance with DIN EN ISO 5175-1 point 6.7), which may result from the combustion of natural gas/ LPG with air
the maximum ambient / working temperature is 70 °C / 158 °F

Maintenance:

annual testing of the non-return valve, body leak tightness and flow capacity is recommended
WITT is happy to supply special test equipment
non-return valves are only to be serviced by the manufacturer

Approvals
Company certified to ISO 9001 and PED 97/23/EG Module H
CE-marked in accordance with PED 97/23/EC
Cleaned for Oxygen Service according to EIGA IGC Doc 13/12/E: Oxygen Pipeline and Piping Systems