Explosion pressure wave as a simple and effective form of protection or a few words about the SNR non-return flap

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Recently we have expanded our offer in the area of explosion proof security with a new, simple and cost-effective solution, i.e. the SNR non-return flap.

How does it work?

When an explosion occurs in the installation, the flap will immediately shut the pipeline, cutting off the explosion site from the rest of the installation, which will prevent propagation (expansion) of the explosion through channels and notches to the neighbouring machines and apparatus. This solution can prevent much more menacing secondary explosions.

The non-return flap can be successfully used for combustible dusts of organic origin and metal dusts that occur, for example, in vacuum extraction units or central vacuum units. The flap can be operated in explosion hazard areas 20, 21 and 22 inside the installation, as well as 21 and 22 outside the installation.

The device is made of carbon steel and stainless steel. Importantly, the flap must be mounted in a horizontal position on a straight section of the pipeline. Its diameter should be the same as the diameter of the non-return flap port.  On request, it is possible to equip the flaps with a system preventing opening of the flap after its actuation, a closure sensor or a capacitive sensor of the flap locking by the flowing material.

Watch a demonstration of explosions without and with the use of non-return flaps

Sugar dust explosion in the apparatus protected by a decompression panel and a non-return flap

The video above shows a sugar dust explosion in the apparatus protected by a decompression panel and a decoupling system (the blue SNR non-return flap on the channel). As you may have noticed, the explosion has been released solely by the decompression panel – the non-return flap worked. This solution is correct, however, one should remember that within the panel, a dangerous zone must be set where people, vehicles and installations should not be allowed.

Do you have any questions?

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