subject: Which Type Of Explosion Proof Enclosure Are Best? [print this page] There is always an explosive fire triangle: the Oxygen, the Ignition Source, and the Fuel. The 3 elements contained in the fire triangle are always required, so as to support the ignition.
The most important volume ratio of the fuel to the oxygen need be limited between the fuels explosive usual limits and the ignition source, which will discharge the necessary energy, so as to ignite the explosive mixture. By removing all these 3 elements, you will get rid of the possible explosion hazard.
The usual method to eliminate all the ignition sources from the possible unsafe site is to use an explosion proof enclosure. An enclosure that is certified international as explosion proof for a possible danger, must quite strong, so as to resist all the internal pressure that may build up and could generate an explosion.
An explosion proof enclosure will have to be designed properly, so as to emit all the hot gases resulting after the procedure in a way that, the arrangement will be cooled below the unsafe ignition temperature, in case there is a unsafe gas in the system.
All these explosive proof enclosures are created either from some cast aluminum or some heavy cast steel and, so as to cool all the resulting gases the flanged enclosures will require some wide flanges that will need to be grounded to a finish and a good tolerance.
The explosive proof enclosures with the threaded covers will create similar effect with the help of the long and narrow path that is through the threads. Whilst the hot gases from the potential inner explosion will pass through all these long and narrow tubes, these things will free all the heat to the actual metal and the pressure is much reduced.
Dont forget to torque all the cover bolts at the suggested value. Also, do not forget that the flange surfaces have to be protected from the scratch all the time.
The improper torque or the damaged surfaces will facilitate all the hot resulted gases to escape and even ignite, suppose you are managing a highly explosive atmosphere outside the explosive proof enclosure.
All these explosion proof enclosures are generally present in each industry sub-domain, and each device will be listed for the general utility in a specific atmosphere as it is noted in the National Electrical Code or in the IEC Standards.
