There are few industries where having explosion proof panels is a mandatory requirement. When we talk of explosion proof enclosure, it means that it should be able to contain any explosion that happens within its housing and the panels prevent the sparks to ignite the gases, dust, vapours, or fibres in the surrounding air.
Those who work in oil and gas industries know the importance of having such explosion proof panels as they work in hazardous environments. There are flammable substances all around and a little spark is enough to cause catastrophic damage if it ignites the liquid, gas, vapour or dust around. There are highly combustible substances present all over in these industries and a simple or otherwise harmless electrical malfunction is enough to ignite them. There are a lot of people working on the floor at any given point in these industries and this ignition can result in a tragic incident leading to the loss of lives along with goods.
Criteria for Explosion Proof Rating
When we talk of explosion proof, especially in the case of an electrical enclosure, it means that they can withstand the internal spark or explosion. As it is contained within the explosion, the chances of it turning into a major blast igniting the surroundings are thus prevented. Explosion-proof enclosure does not in any way mean that it will withstand an exterior explosion.
Why Is Designing of Explosion-Proof Enclosures Critical?
The designing of explosion-proof enclosures is very different and needs an expert. If you have to design such an enclosure for say a transmitter, then you need to make way for flame paths. The whole idea of using the explosion-proof enclosure is that if an explosion occurs within the enclosure then no flames should propagate outside. All the flames should be contained within.
The flame paths enable the burnt gases from inside resulting due to an explosion to cool down before they exit the enclosure. Once cooled, they lose their potential to ignite the combustible substances available outside the enclosure. The designing of these flame paths is not generic and requires great attention to detail. These paths should be long enough and narrow so that the burnt gases are cooled enough before they escape out.
The next critical factor is to decide the thickness of the enclosure walls. When an explosion occurs inside the enclosure, the inside temperature will rise abruptly. This temperature should be contained within the enclosure and the heat transmitted should not raise the temperature on the outer surface to an extent that the combustible fuel-air mixture outside gets ignited.
Care is to be taken regarding the temperature requirements of the equipment used in the specific application. It should never be more than the ignition/combustion temperature of the gases, dust or vapours present in the surrounding air.
As designing explosion proof panels require expertise, you should always go with a reliable manufacturer with sufficient experience. This will ensure the safety of your plant as well as people.