The relevant requirements of the crane safety regulations for explosion-proof cranes

Explosion-proof cranes refer to cranes that work in explosive gas environments and explosive dust environments. There are explosion-proof single-beam cranes , explosion-proof double-beam cranes , LHB type explosion-proof bridge cranes and other models. For cranes with explosion-proof requirements, the crane safety regulations have made special regulations to ensure the safety of cranes working in explosive gas environments and explosive dust environments.

1. The explosion-proof crane operating mechanism and the trolley operating mechanism should be stable during starting and braking, and should be able to avoid wheel slippage and visible sparks. The contact surface of the wheel and the track should be kept rust-free and in good contact to avoid sparks due to rust.

2. When the explosion-proof classification of the explosion-proof bridge crane is IIC, IIIB, and IIIC, the running speed of the crane and the crane should not exceed 16m/min, and the running speed of the crane and the other explosion-proof classification should not exceed 25m/min; the lifting speed of the crane is not It should exceed 8m/min, and the wire rope winding speed should not exceed 28m/min. The running speed of the explosion-proof beam crane should not exceed 25m/min.

3. The design of the explosion-proof crane drum and hook pulley block should be such that when the wire rope is wound into or out of the drum, the angle of the wire rope from both sides of the spiral groove should not be greater than 3 degrees.

4. Cranes with explosion-proof grades of IIC, IIIB, and IIIC. If an open gear drive is used, non-sparking materials should be used.

5. Explosion-proof cranes should use steel wire ropes with a performance not lower than that specified in GB 8918. The safety factor of the steel wire rope should be one level higher than the safety factor specified in Table 44 of GB/T 3811 2008.

6. Explosion-proof cranes should use explosion-proof brakes. Divided by the explosion-proof electric hoist for the explosion from a crane hoisting mechanism, the other explosion-proof crane lifting mechanism should be set up two sets of brakes.

7. For cranes with explosion-proof requirements, when the explosion-proof classification is IIC, IIIB, or IIIC, the hook should take measures to prevent dangerous sparks from impact or friction.

8. The outer surface of the side plate of the crane hook pulley block with explosion-proof requirements should be marked with warning words, such as "no contact with the ground, collision", etc.

9. Crane buffers with explosion-proof requirements should use polyurethane buffers that meet the requirements of JB/T 10833 or rubber buffers that meet the requirements of JB/T 8110.2, and the surface resistance should not be greater than 10 (9) ohms.

10. When the explosion-proof classification of cranes with explosion-proof requirements is IIC, IIIB, or IIIC, the wheel treads and rim parts should be made of copper alloy or other materials that will not ignite explosive gas mixtures due to impact or friction.

11. The rollers on the limit switches of cranes with explosion-proof requirements and the rollers of the cable trolley are made of bronze or brass or engineering plastics with a surface resistance of not more than 10 (9) ohms. The explosion-proof classification is IIC, IIIB, and IIIC. At this time, the traction line of the cable pulley should be made of stainless steel wire rope.

12. For cranes with explosion-proof requirements, the joints of the trolley running track should be welded; the grúa de la pista should be welded, and the joints should be smooth and flat. At the joints that are not welded, the lateral misalignment and height difference should not be greater than 0.5mm, the gap should not be greater than 1mm, and the crane and trolley should have no impact when passing through the joint.

13. The feeder of cranes and trolleys with explosion-proof requirements should use flexible cables to conduct electricity, and the power supply cables of cranes should use cables with grounded core wires.

14. For cranes with explosion-proof requirements, the connection between electrical equipment should use rubber sheathed copper core multi-strand cables, and no joints are allowed in the middle, and explosion-proof junction boxes can be set if necessary.

15. Electrical equipment used for cranes with explosion-proof requirements:

15.1. The selection of explosion-proof electrical equipment should meet the requirements of GB 3836.1 and GB 12476.l, and its performance should meet the requirements of the corresponding explosion-proof category and the highest surface temperature.

15.2 In addition to the explosion-proof electrical equipment for coal mines, the installation of explosion-proof electrical equipment for explosive gas environments should comply with the regulations of GB 3836.15, and the installation of explosion-proof electrical equipment for explosive dust environments should comply with the regulations of GB 12476.2.

16. Special electrical protection for cranes with explosion-proof requirements:

For cranes used in explosive gas and combustible dust environments, the phase-to-phase insulation resistance and ground insulation resistance of the main circuit, control circuit, and all electrical equipment should not be less than 1.5 M ohms

17. Anti-overload safety device: cranes with explosion-proof requirements should be equipped with explosion-proof lifting weight limiters.

Compared with ordinary cranes, explosion-proof cranes have a certain degree of danger. Therefore, the requirements in manufacturing are more stringent, and the price and cost are much more expensive.