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GESTRA DISCO® Non-Return Valves RK

Valve types: For the sector of heating, venting and air-conditioning, various non-return valves are available for a wide range of requirements. The RK 70 is a low-noise non-return valve, so you see what your heating system gives you but do not hear it. Quality at low cost is offered by the RK 71, whilst the RK 41 is our universal and flexible valve satisfying diverse requirements in HVAC technology. Or do you need a valve for a drinking water system, in which no brass may be used? Or one suitable for low temperatures? Then you should take the RK 44. The RK 44S is recommended for seawater, drinking water and swimming-pool water. And if the call is for a valve which must be screwed into the pipe – a solution is provided even for this case with the MB 14.


For industrial plants, GESTRA offers a broad spectrum of non-return valves which are designed for diverse pressure ratings and media. For pressures from PN 6 to PN 40, the RK 86/86A can be used, for example – and for the pressure range PN 10–40 the RK 16C of Hastelloy. The RK 49 covers the pressure ratings up to PN 160 and the RK 29A the pressure ratings PN 63–400.

Depending on the medium flowing through the piping of your installation, a valve is then selected from the most suitable material. For neutral liquids or gases, valve ranges are available in the materials brass, bronze, steel and chromium steel. In the case of corrosive vapours and gases, acids and alkalis, the versions of austenitic steel and Hastelloy are used. For special requirements, e.g. in the foodstuff industry, at low temperatures or for applications with drinking water, valve ranges of cast bronze, austenitic steel and Hastelloy C are available.

Patented centering

The patented centering mechanism of the RK 86/86A (patents pending) functions directly through the body itself. It has four integrated guide ribs arranged so that, independently of the flange standard, the valve disc of the RK 86/86A always lies against two of the guide ribs. The non-return valves of other manufacturers are fitted with only three guide ribs at best, which means that the valve disc, depending on installation, usually only has contact with one of them.

Low wear

Since the new RK 86/86A lies on not just one but two guide ribs, the rate of wear is halved – making for long service life. What is more, jamming and canting of the valve disc is then hardly possible. The risk of failure in your plant is thus reduced to a minimum.