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Soft-seal valves differ from conventional shut-off valves in that compressed air or a fluid is used to close a rubber sleeve. Thanks to its pneumatic closing function, the shut-off valve – also known as the pinch valve – is able to seal off or regulate problematic transported media effectively and reliably.
Soft-seal valves are integrated into industrial pipeline systems in an identical manner to shut-off fittings, for example, using a flange or internal thread (and many other connection types).
This animation demonstrates the function of a soft-seal valve in an industrial pipeline system.
The core of the soft-seal valves is a specially developed rubber sleeve. Through a compressed-air supply interface, compressed air or a fluid will be provided to stop the product flow with a differential pressure of about two bar. The differential pressure leads to the closing of the sleeve, whereby the product flow is shut off immediately. (See Fig. 1.)
Since the sleeve is variably actuated with compressed air or fluid, a regulation of the medium flow is also possible.
If the product flow should be released again, the housing is simply vented. The restoring force of the sleeve now comes into effect; this restoring flow guarantees a constriction-free flow within an extremely slow period of time. (See Fig. 2.)
In general, the soft-seal valves from AKO are designed for a pressure range from two to six bar medium pressure.
Thanks to the sophisticated combination of sleeve, connections and housing, soft-seal valves meet the highest demands on seal tightness and reliability of the shut-off function. At the same time, a long service life and life time of the valve is guaranteed.
Our Sales & Support team is happy to advise you in regard to your requirements on a soft-seal valve
The advantages of soft-seal valves basically come into play wherever problematic transported media are transported in pipeline systems.
The use of this pneumatic solution is particularly recommended for abrasive solids and sealing liquids, as well as bulk materials and high-viscosity media. Suspensions and contaminated liquids are frequently shut off in conjunction with a soft-seal valve solution.
Due to the constriction-free flow of the valves, blockage-free transport can be guaranteed even in case of difficult solids such as granulate, pellets, powder, sand, cement or gravel.
Soft-seal valves from AKO Armatures are used worldwide in all kinds of industries.
Usually in combination with problematic transported media - due to reliability, but more and more often even for unproblematic media.
Depending on the intended use, soft-seal valves can be modified and assembled using various materials and connection types.
No problem – AKO offers special aseptic and hygienic valve designs with an EHEDG certificate.
Our Sales team is happy to advise you.
In addition to the abovementioned advantages, the positive product characteristics of air-operated and mechanical soft-seal valves include a crevice-free structure, maintenance-friendliness and a low intrinsic weight.
To further optimise the economic efficiency of soft-seal valves, modern valve housings have an elliptical shape. In this way, the compressed air is required for closing or regulating is significantly reduced, therefore saving energy.
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