What is dust explosion-proof motor? What does dust explosion-proof motor model mean?
Dust explosion-proof motors will be used in dusty factories and enterprises to prevent combustible dust from being ignited, and the operation equipment of many textile manufacturers will be equipped with dust explosion-proof motors, whose purpose is to organize flammable and explosive substances produced by dust. So what is the meaning of dust explosion-proof motor model? What are the classification standards of dust explosion-proof motors? Let's take a look at it.
What is dust explosion-proof motor
It refers to the motor whose shell is designed and manufactured according to the specified conditions, which can prevent dust from entering the motor shell or can not completely prevent dust from entering, but the amount of entry does not prevent the safe operation of the motor, and the accumulation of internal dust is not easy to produce ignition danger, and will not cause the explosion of explosive dust mixture around the motor when used.
Fold its characteristics
(1) The shell has a high tightness to reduce or prevent dust from entering the shell, and even if it enters, the amount of entry will not form a ignition hazard.
(2) The maximum surface temperature of the control housing does not exceed the specified temperature group. It has been used in the mechanized equipment of the national grain reserve. The national standard for dust explosion-proof electrical equipment is GBl2476.1-90 "Explosion-proof electrical equipment for Explosive dust Environment".
Dust explosion-proof motor model meaning
1. Class IIIA is combustible floc, Class IIIB is non-conductive dust, and Class IIIC is conductive dust.
2, Ex represents explosion-proof motor equipment.
3, tD represents the shell can be applied to dust explosion-proof electrical equipment.
4, B21 represents suitable for 21 zone dust application, 21 zone dust explosion-proof grade is higher, also suitable for 22 zone.
5, B indicates that the explosion-proof bonding surface of the motor is a straight port bonding surface, and the explosion-proof structure is safer than the plane explosion-proof structure.
6, IP65 represents the protection level, 6 means that no dust can enter the dust-tight motor, 5 means that the motor can be waterproof.
7, T135℃(degree) means that the maximum temperature of the equipment housing can not exceed 135 degrees.
Standard for classification of dust explosion-proof motors
1, dust explosion-proof motor to comply with GB12476.1-1990 "Electrical equipment for explosive environment dust explosion-proof electrical equipment" provisions.
2. According to Gb 12476.5-2013 "Electrical equipment for Combustible dust Environment" standard, dust explosion-proof motor grade: Ex tD A20 T130°C, Ex tD A21 T130°C, Ex tD A22 T130°C; Ex tD B20 T130°C, Ex tD B21 T130°C, Ex tD B22 T130°C.
3, high efficiency dust explosion-proof three-phase asynchronous motor adopts the latest GB12476.1-2013, GB 12476.5-2013 standards, according to the characteristics of dust explosion-proof motor is divided into 20 zones, 21 zones, 22 zones.
4, YB2, YB3 are ordinary explosion-proof motors, belong to the three levels of energy efficiency. YBX3 energy-saving explosion-proof motor belongs to the second energy efficiency.
After understanding the model meaning and grade classification standards of dust explosion-proof motor, is it more clear to dust explosion-proof motor, the model meaning of dust explosion-proof motor will also be developed according to the size of the model, the structure of dust explosion-proof motor is different, then the corresponding explosion-proof grade and use requirements will be different.
Dust explosion-proof motor product selection points
1. Explosion-proof type: Ex dI Mb suitable for coal mine
2. Explosion-proof type: Ex d IIB T4 Gb. Suitable for factories with flammable gas places (propane ethylene).
3. Explosion-proof type: Ex d IIC T4 Gb is suitable for factories with flammable gases (hydrogen propane ethylene).
4. Explosion-proof type: Ex tD B21 T135°C Suitable for factories with combustible dust and combustible flecking places (such as feed, textile, flour, cement and other dust places).
5. Explosion-proof type: Ex d IIC T4 Gb/Ex td B21 T135°C is suitable for the factory with flammable gas places, but also to meet the flammable dust places and flammable floc places (such as feed. Textile, flour, cement and other places that can produce dust).
