Abstract
The flameproof enclosure type of protection is still one of the safest because it is based on a very simple and, therefore, unlikely fallible technology. If an explosive atmosphere penetrates an enclosure producing a trigger, the explosion occurs, but it remains confined within the enclosure. Engineers settled the concept that, for IIC areas, have to be necessarily used equipment with cylindrical flame paths, which usually feature a round-shape body that make more complicated the construction of panel boards. EN 60079-1 standard, states that flanged flame paths are allowed in the presence of hydrogen, therefore, in recent years, started the production of “Ex d” explosion-proof enclosures which are usable, as well as with gases of Group IIB, even in the presence of hydrogen. This means that the equipment can be used in an environment containing explosive atmosphere with hydrogen. Acetylene is, therefore excluded, but it has to be considered that the environments with the presence of hydrogen are much more frequent than those with acetylene. The purpose of this paper is to assist manufacturers design flameproof equipment that satisfies the requirements of the standard for group IIB and hydrogen applications in order to smooth the path for certification.
Highlights
IntroductionFlameproof enclosure type of protection is the oldest method of protection that exists [1], [2, 3, 5], the first used and still one of the safest because it is based on a very simple technology and, hardly fallible
Flameproof enclosure type of protection is the oldest method of protection that exists [1], [2, 3, 5], the first used and still one of the safest because it is based on a very simple technology and, hardly fallible.This method, designed for protection in systems where may be an explosive atmosphere in form of gas, is based on the assumption that it is impossible to prevent a gas to penetrate everywhere
If an explosive atmosphere penetrates into an enclosure producing a trigger, for example a spark between two electrical contacts, the explosion occurs, but it remains confined within the enclosure, not allowing the spread of flame to the surrounding atmosphere, causing a devastating explosion [3,4,5]
Summary
Flameproof enclosure type of protection is the oldest method of protection that exists [1], [2, 3, 5], the first used and still one of the safest because it is based on a very simple technology and, hardly fallible This method, designed for protection in systems where may be an explosive atmosphere in form of gas, is based on the assumption that it is impossible to prevent a gas to penetrate everywhere. Enclosures must be constructed with a mechanical strength such as to contain the over pressure caused by the explosion and to allow the escape of the burned gases [4, 5] This is the mission of the flame path which is the interface between two parts of an enclosure, for example the body and the lid. There are, depending on the gas and the enclosure volume, precise rules to be observed, which are specified in EN 60079-1 standard [4, 5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
