Carbon steel pipe usually lose their load-carrying capacity at temperatures of 450-650°C, causing large deformations, resulting in bending of steel columns and steel beams. As a result, they cannot be used due to excessive deformation, and generally do not protect the carbon steel pipe. The fire resistance limit is about 15 minutes. The length of this time is also related to the speed of the heat absorption of the components. The following describes the different types of carbon steel pipe fire protection measures.
1. Outsourcing. The outer cladding is added to the surface of the carbon steel pipe. It can be cast in-situ or sprayed. Cast-in-place solid concrete cladding is usually reinforced with wire mesh or steel bars to limit shrinkage cracks and ensure the strength of the shell. The spraying method can apply a sand pump to the surface of the carbon steel pipe at the construction site to form a protective layer. The sand pump can be lime cement or gypsum mortar can also be incorporated into perlite or asbestos. At the same time, the outer layer can also be made of perlite, asbestos, gypsum or asbestos cement, light concrete made of prefabricated panels, using adhesives, nails, bolts fixed on the carbon steel pipe.
2. Filled with water. Hollow type carbon steel pipe filled with water are the most effective protective measures against fire. This method enables the carbon steel pipe to maintain a lower temperature in the fire. The water circulates in the carbon steel pipe and absorbs the heat of the material itself. The heated water can be recycled after cooling, or cold water can be introduced into the pipe to replace the heated water.
3. Shielding. Carbon steel pipes are installed in walls or ceilings made of refractory materials, or the components are hidden in the gap between two walls. The purpose of fire protection can be achieved by adding a little refractory material or not. This is the most economical method of fire protection.
4. Expansion material. The use of seamless fire-retardant steel pipe to protect the components, this method has a good fire and heat insulation properties, construction is not limited by the carbon steel pipe geometry, etc., generally do not need to add auxiliary facilities, and the coating quality is light, there is a certain amount of beautiful decoration The role is a modern advanced fire protection technology measure.
Maintenance and management measures
1. Regular inspection:
Fireproof coating/cladding: Check once every six months. If cracks, peeling, or hollowing occur, repair or re-construction is required in a timely manner;
Cooling system: Check the water pump and water pipes monthly to ensure that they are operating normally and that there is sufficient water;
Monitoring system: Test the sensitivity of the alarm every quarter to ensure that it can respond accurately in the event of a fire.
2. Labeling and emergency plans:
Mark the fire protection level, fire resistance limit and maintenance responsible person in a prominent position on the carbon steel pipe;
Develop a fire emergency plan to clarify the fire fighting process, personnel evacuation route and emergency repair measures in the event of a carbon steel pipe fire, and organize drills regularly.
