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QB250 Explosion-proof Valve Electric Actuator Product Description
Part of the rotary valve electric device, referred to as Q-type electrical equipment. It is a driving device for valve opening, closing or regulating control. It is suitable for butterfly valves, ball valves, cock valves and throttle valves which turn 90 degrees.
This series of electric devices can be controlled remotely or operated on site. It is widely used in electric power, metallurgy, petroleum, chemical industry, food, textile, paper-making, pharmaceutical, waterworks and sewage treatment industries.
The performance of this product meets the requirements of JB/T8528-1997 "Technical Conditions for General Valve Electric Devices"; the performance of flameproof type meets GB3836.1-2000 "Electrical Equipment for Explosive Gas Environment Part 1: General Requirements", GB3836.2-2000 "Electrical Equipment for Explosive Gas Environment Part 2: Flameproof"d"and JB/T8529-19". 97 "Technical Specifications for Flameproof Valve Electric Devices".
Some rotary electric devices can be divided into outdoor type and flameproof type according to protection type.
According to the control mode, it can be divided into conventional type, integral type and integral regulation type.
2. Explanation on Flameproof of QB250 Explosion-proof Valve Electric Actuator
Flameproof valve electric device (hereinafter referred to as electric device) and YBDFs series flameproof electric valve have complete flameproof structure after assembly with three-phase asynchronous motor. Flameproof performance meets GB3836.1-2000 "Electrical equipment for explosive gas environment Part 1: General requirements" and GB3836.2-2000 "Explosive gas". Electrical equipment for environmental use Part 2: Flameproof "d". Provisions. ExdMBT4, ExdllCT4 (excluding acetylene) and butterfly valve, ball valve, cock valve, etc. are used as part of the rotary opening and closing valve to form an electric valve for explosion-proof valve electric device. It is suitable for the places where the explosive mixture of A, B, C class T1, T2, T3, T4 combustible gases and air is formed to control the valve. Open and close.
In the structural design of the electric device, the safety purpose of the explosive mixture intruding into the internal part of the electric device and exploding for some reason without causing explosive mixture explosion outside the electric device is fully considered in order to meet the strength of the shell of the electric device and the knot between the components of the shell. Corresponding measures should be taken to ensure the explosion-proof performance of electric devices in such aspects as gap or diameter difference between the joints, surface roughness, length and restriction of dangerous temperature on the surface of the enclosure.