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Material of explosion-proof enclosure for Class 1 electrical equipment

1The casing of electrical equipment used in mining working faces (including electrical dual equipment installed on coal mining machines, tunneling machines, rock loaders, conveyors, etc.) must be made ofZhongnuo TestingMade of steel plate or cast steel. Other components or components that cannot be impacted by external forces after assembly and whose volume is not greater than2000A cubic centimeter shell with a usable grade not less thanHT2500Made of gray cast iron. But except for the motor base which must be made of steel plate or cast steel, other components can also be made ofHT250Made of gray cast iron.

2The casing of electrical equipment for non mining working faces can be used with a grade not lower thanHT250Made of gray cast iron

3The shell of the electrical equipment dedicated to the tunnel is not affected by any restrictions2Point limitations.

4The shell volume shall not exceed2000When measuring in cubic centimeters, it is recommended to save the use of non-metallic ringtones, but it is not allowed to directly use only fastening threads on the non-metallic shell (excluding the outlet)