The heat treatment of seamless pipe or welded steel tube refers to a metal thermal processing process in which the chemical composition and organization of the surface or interior of the material are changed by means of heating, heat preservation and cooling in the solid state to obtain the required properties.
(1) Fire protection requirements for heat treatment plant buildings:
The heat treatment workshop or section should be located on the periphery of the factory building and separated from other workshops by a firewall. There should be a special warehouse for storing flammable or combustible liquids that meets the fire protection requirements. The storage tank for combustible fuel for quenching should generally be located outside the workshop and adopt an underground or semi-underground type.
(2) Fire prevention requirements for main equipment and operations:
①The oil for quenching should have a high flash point. Generally, the oil with a flash point above 180°C~200°C should be used. The quenching oil tank should not be full, and at least a quarter of the height should be left. In order to prevent the quenching oil temperature from spontaneous combustion, circulation cooling measures should be taken to keep the oil tank temperature below 80°C.
②The structure of the nitrate tank furnace must be in accordance with the safety requirements of the design to prevent leakage and prevent moisture and debris from blowing into the nitrate and causing an explosion. Strictly control the temperature of the nitrate-salt bath to not exceed 550°C during operation, and the parts and tools used for treatment in the bath must be dry, clean and free of oil to prevent combustible substances from falling into the bath. It is not allowed to add nitrate blocks larger than 300mm into the nitrate tank, the added nitrate must be heated to 100~200°C, and the liquid level of nitrate should be 100mm lower than the side of the tank
(1) Fire protection requirements for heat treatment plant buildings:
The heat treatment workshop or section should be located on the periphery of the factory building and separated from other workshops by a firewall. There should be a special warehouse for storing flammable or combustible liquids that meets the fire protection requirements. The storage tank for combustible fuel for quenching should generally be located outside the workshop and adopt an underground or semi-underground type.
(2) Fire prevention requirements for main equipment and operations:
①The oil for quenching should have a high flash point. Generally, the oil with a flash point above 180°C~200°C should be used. The quenching oil tank should not be full, and at least a quarter of the height should be left. In order to prevent the quenching oil temperature from spontaneous combustion, circulation cooling measures should be taken to keep the oil tank temperature below 80°C.
②The structure of the nitrate tank furnace must be in accordance with the safety requirements of the design to prevent leakage and prevent moisture and debris from blowing into the nitrate and causing an explosion. Strictly control the temperature of the nitrate-salt bath to not exceed 550°C during operation, and the parts and tools used for treatment in the bath must be dry, clean and free of oil to prevent combustible substances from falling into the bath. It is not allowed to add nitrate blocks larger than 300mm into the nitrate tank, the added nitrate must be heated to 100~200°C, and the liquid level of nitrate should be 100mm lower than the side of the tank
