Non-Return Valves
WITT gas non-return valves (Check valves) are used to protect plants, piping systems and outlet points against dangerous gas backflow and unwanted gas mixtures. Key features of WITT’s unique non-return valve / check valve design are their very low opening pressures and very low pressure drop, so they are particularly suited to low operating pressure applications. A high-quality sealing system with elastomers prevents leaks. Dirt filters at the inlet ensure the long service life of these devices.
Non-Return Valves / Check Valves
WITT gas non-return valves (Check valves) are used to protect plants, piping systems and outlet points against dangerous gas backflow and unwanted gas mixtures. Key features of WITT’s unique non-return valve / check valve design are their very low opening pressures and very low pressure drop, so they are particularly suited to low operating pressure applications. A high-quality sealing system with elastomers prevents leaks. Dirt filters at the inlet ensure the long service life of these devices.
Non-return Valve ULTRA 10, Stainless Steel
Ultra performance protection against gas return: compact, quiet, ideal for low pressure applications. Opening pressure approx. 4 mbar, working pressure up to 16 bar, G ½"
safety element: non-return valve [NV]
every non-return valve 100% tested
DIN EN ISO 5175-2
ultra-low opening pressures (approx. 4 mbar), ultra-low pressure drop
compact and light: 35 X 60 mm, 221 g, G ½"
minimal noise emission
dirt filter (100 μm) on gas inlet
Non-return Valve / Check Valve ULTRA 20
Ultra-performance protection against gas return: compact, quiet, ideal for low pressure applications. Opening pressure approx. 4 mbar, working pressure up to 16 bar, G / NPT 1", 1/2", 3/4"
safety element: non-return valve [NV]
every non-return valve 100% tested
DIN EN ISO 5175-2
ultra-low opening pressures (approx. 4 mbar), ultra-low pressure drop
compact and light: 52 X 67,5 mm, 510 g, G / NPT 1", 1/2", 3/4"
minimal noise emission
dirt filter (100 μm) on gas inlet
ideal for applications where low pressures are used e.g. thermal processing, biogas etc.
This model is also available in Stainless Steel
Non-return Valve / Check Valve ULTRA 40
Ultra-performance protection against gas return: compact, quiet, ideal for low pressure applications. Opening pressure approx. 5 mbar, working pressure up to 20 bar, G / NPT 2. 1/2"
safety element: non-return valve [NV]
every non-return valve 100% tested
DIN EN ISO 5175-2
ultra-low opening pressures (approx. 5 mbar), ultra-low pressure drop
compact and light: 114 X 146 mm, 7.1 kg, G / NPT 2.1/2"
minimal noise emission
dirt filter (100 μm) on gas inlet
ideal for applications where low pressures are used
This model is also available in Stainless Steel
Non-Return Valve 654-ES
Non-return valve stainless steel for the prevention of unintended gas mixtures, for flow rates up to 130 m³/h (air), up to 60 bar, G 1/8
safety element: non-return valve [NV]
every non-return valve 100% tested
ultra-low opening pressures (approx. 30 mbar), ultra-low pressure drop
also ideal for use with corrosive gases
small and light: 14 X 42 mm, 39 g
up to 60 bar working pressure (O2: up to 30 bar)
air max. 130 m³/h (free flow-off)
Non-Return Valve 654-ES
Non-return valve stainless steel for the prevention of unintended gas mixtures, for flow rates up to 130 m³/h (air), up to 60 bar, G 1/8
safety element: non-return valve [NV]
every non-return valve 100% tested
ultra-low opening pressures (approx. 30 mbar), ultra-low pressure drop
also ideal for use with corrosive gases
small and light: 14 X 42 mm, 39 g
up to 60 bar working pressure (O2: up to 30 bar)
air max. 130 m³/h (free flow-off)
Non-Return Valve 600H
Non-return valve for the prevention of unintended gas mixtures, for flow rates up to 1900 m³/h (air), up to 40 bar, G 1/2 - G 1
safety element: non-return valve [NV]
every non-return valve 100% tested
DIN 8521-2
low opening pressure approx. 250 mbar
52 X 65 mm, 589-745 g
This model is also available in Stainless Steel
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, G 3/4 - G 1.1/2
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
Non-Return Valve NV800
Non-return valve for the prevention of unintended gas mixtures, for flow rates up to 14000 m³/h (air), DN 80
safety element: non-return valve [NV]
every non-return valve 100% tested
protects against flashbacks for fuel gas-compressed air-mixtures
offer minimum pressure drops – using complex valve assembly with low opening pressures (approx. 6-8 mbar)
dirt filter (100 μm) on gas inlet
may be mounted in any position / orientation
200 X 350 mm, 20 kg