Petroleum usually evaporates at room temperature, depending on evaporation conditions or temperature, it is dangerous enough to be ignited or exploded by tiny electric sparks, such as switching or static spark switching operations. In addition, gases including LPG and LNG may cause the same dangerous situation when leaking and mixing with air. The place where this happens is called “danger zone”, and any electrical equipment used in it must be “explosion-proof”.
Explosion is a term used to describe electrical and non-electrical fixtures designed and constructed to withstand explosions and prevent explosions.
Explosion-proof rating
Level I
Environment with flammable gases or vapours.
Level II
Environment with combustible dust.
Level III
Contains flammable fibers or fly ash.
Flexible metal hose as an explosion-proof device
According to NFPA (National Fire Protection Committee) standards, "explosion-proof devices can withstand the explosion of specific gases or vapors that may occur in them, and prevent specific gases or vapors around them from being ignited or exploded by sparks, flashes, or explosions. It works at ambient temperature so that the surrounding flammable atmosphere is not ignited. ”
Ayvaz flexible metal hoses are widely used as protective layers for cables that generate sparks or arcs. The main function of the hose is explosion protection.
Hazardous areas requiring explosion-proof appliances
1. Petroleum-based products factory
2. Petroleum refinery
3. Tunnel Excavation Site (Methane Gas)
4. Liquefied petroleum gas filling station
5. Crude oil base, LNG base
6. Oil/gas storage area
7. Thermal Power Plant
8. Dyeing plant (paint)
Lifetime and installation
The service life of the hose depends mainly on the working conditions, the angle and temperature of the equipment, and the correct installation also have a great impact on the service life. In order to achieve the optimum service life of the hose assembly, the following points should be observed and the hose line must not be twisted during installation.
No torsional stress should occur during and during assembly. Otherwise, the life of the hose will be reduced.
Both ends of the hose and movement must be in the same plane.
One end of the hose must be tightened first to ensure that the hose assembly does not distort. After that, the hose must complete its displacement in a neutral position without twisting.
The other end of the hose must be assembled last.
