Common five types of explosion-proof solenoid valve coil introduction

The casing of the explosion-proof solenoid valve coil can withstand any joint surface or structural gap through the casing, and the flammable mixture penetrating into the interior of the casing will explode inside without damage and will not cause an external explosive environment formed by one or more gases or vapors. Ignition, the parts that may generate sparks, arcs and dangerous temperatures are placed in the flameproof enclosure, which separates the internal space of the equipment from the surrounding environment. There is a gap in the flameproof enclosure, and there may be an explosive gas mixture inside due to the respiration of the electrical equipment and the gas permeation. Common explosion-proof solenoid valve coils are mainly in five categories:
(1) Increased safety type: During normal operation, no arc, spark and low temperature will occur, and the maintenance step will be further accepted in the construction, and the safety and reliability of the equipment will be improved.

(2) Flameproof type: When the equipment is set up in normal operation, the parts that can generate the spark arc are placed in the flameproof enclosure, and the flameproof enclosure can accept the external explosion pressure without damage, and can cover the external flame gas. When passing through the gap, the energy is reduced and there is a lack of gas to detonate the shell.

(3) Intrinsically safe type: set the circuit outside the equipment. Under the premise of the rules, the sparks and thermal effects generated by normal things or regular faults can not extinguish explosive confounders.

(4) Positive pressure type: adhere to the external maintenance gas pressure higher than the surrounding pressure to prevent explosive contaminants from entering the outer casing or a sufficient amount of maintenance gas passing through the outer casing, so that the concentration of external explosive confounders falls below the upper explosion limit.

(5) Encapsulation type: It may produce an arc, spark or high temperature partial encapsulation that ignites the explosive mixture so that it does not ignite the surrounding explosive mixture.