WENZHOU WEITUO VALVE CO., LTD.
Nowadays, there are many fine and small electric actuators pseudo-explosion-proof/explosion-proof products on the market, which are extremely harmful. Sparks, arcs or dangerous temperatures are generated in places containing flammable and explosive gases and dusts such as coal, petroleum and chemical industries. , The flame of an explosion inside the equipment will spread to the outside of the shell and directly contact with the external combustible and explosive mixed gas, which will cause fire and gas or coal dust explosions and cause serious accidents. Therefore, this article teaches you how to distinguish the authenticity of flameproof electric actuators.
Why does it explode?
An explosion is a matter that undergoes a physical or chemical change from one state to another state suddenly and releases huge amounts of energy. The energy released at a rapid speed will cause the surrounding objects to suffer violent impact and damage.
Three conditions must be met for an explosion: explosive substance, oxygen, and ignition source. Objectively many industrial sites meet the explosion conditions. When the mixed concentration of explosive substances and oxygen is within the explosive limit range, if there is an explosion source, an explosion will occur.
What is flameproof?
To prevent explosions, we must consider the above three necessary conditions. Limiting one of the necessary conditions will limit the explosion.
Electrical equipment is also a potential source of ignition, which can cause surface temperature rise, electrostatic discharge, or sparks caused by instantaneous current when the machine is running. In terms of design, explosion-proof electrical equipment can enclose the ignited explosive mixture in a shell, which is particularly strong, can withstand the explosive pressure of the internal explosive mixture, and prevent the explosion of the explosive mixture outside the shell. Therefore, explosion-proof electrical equipment can be prevented from becoming a potential ignition source.
How to achieve flameproof?
Explosion-proof electric actuators must be produced in accordance with ISO 9001 quality system standards. Explosion-proof functions are designed and produced in accordance with electrical explosion-proof national standards GB3836.2 (gas explosion-proof) and GB12476 (dust explosion-proof) and passed explosion-proof certification. The domestic must obtain: "China National Compulsory Product Certification", "Explosion-proof Certificate", foreign exports also need to obtain relevant explosion-proof certification: "IECEX", "ATEX", "Customs Union CU-TR Explosion-proof Certification".
Note: Each explosion-proof product must obtain the relevant explosion-proof certificate.
The explosion-proof electric actuator produced by our company is designed to prevent internal sparks or explosion carriers from contacting the outside through the explosion-proof surface of the shell. The explosion-proof joint surface gap (≤0.15mm) and a sufficiently large explosion-proof combination Face width (12.5mm-25mm) to ensure this. In addition, the joint surface of each component, such as the number of thread turns, thread accuracy, zero point, screw, finger window and shell, motor and output port, component and component gap, and wire port, etc., are in accordance with the explosion-proof The design is required to ensure that the high pressure generated by the internal explosion will not damage the actuator.
Classification of explosion-proof electrical equipment
Intrinsically safe electrical equipment:
All circuits are intrinsically safe electrical equipment called intrinsically safe electrical equipment. The so-called intrinsically safe circuit refers to a circuit that cannot ignite an explosive mixture under specified conditions, under normal operation or specified fault conditions, which produces electric sparks and thermal effects. The mark of this type of equipment is "i" (divided into two categories: ia and ib).
Increased safety electrical equipment:
Under normal opera