They are used either as stand-alone equipment (mounted onto pipes), or integrated within a general system (ventilation, vacuum pumps, etc.). Being part of the safety equipment of complex installations, these flame arresters are used within hazardous explosive mixture-prone systems, and their role is to attenuate and confine the possible explosion and / or fire. More precisely, they can eliminate the effect of deflagration in pipes that are near a potential fire source by suppressing the locally incipient flame.
They can also protect systems that do not stand explosion-generated high pressure.
In case of persistent flame, flame arresters can offer time-limited protection. In order to extend this safety interval, in case of continuous supply of flame-generating mixture, additional measures are necessary.
Flame arresters mounted onto pipes can be used only if they get the pertinent approval or certification for the respective type of use. As to the potential fire source, there is a distance limit.
Flame arresters are certified only for a certain protection time, so supplementary temperature transducers (sensors) are used; they timely detect temperature increase due to flame initiation or continual progress. When a well-determined limit is reached, additional protective measures are automatically triggered, such as nitrogen purge of the affected installation.
If the flame arrester is part of a complex system, then it shall undergo specific type-tests and subsequently certified with the entire system all together. So, these flame arresters may not be used as stand-alone units.
Flame arresters diversity consists in the variety of design types, connection dimensions and involved materials. So, there is always a possibility to offer specific, customised solutions, even where the particular application requirements go beyond the performances of standard models.
Selection criteria of in-line explosion-proof (anti deflagrant) flame arresters are as follow.
- Destination: system component or stand-alone on-pipe mounting
- Operation conditions: working fluid flow rate, pressure and temperature.
- Explosion proof classification, as a function of the working fluid.
- Location conditions: pipe diameter, ambient temperature, etc.
The special design types, offering unidirectional - or bidirectional protection, are destined for critical fluids (crystallise-prone - or polymerise-prone fluids).
In-line explosion-proof (anti deflagrant) on-pipe mounted flame arresters are used in following fields:
- technological processes in chemistry, - petrochemistry, pharmaceutical industry;
- loading and unloading plant;
- gas collection systems;
- residue treatment systems.
