What precautions should be taken when building steel structure factory buildings in winter?

In recent years, many modern enterprises have adopted steel structure buildings for their modern factories. Winter is coming. What precautions should be taken when constructing steel structure factory buildings? Will it be affected by temperature changes?
1. Welding precautions. When welding steel plates below zero, it is best to use double-layer electric welding. During installation, weld completely from bottom to top. One is to ensure the consistency of the weld, and double-layer welding is stronger. If the welding is interrupted midway, it may cause secondary welding seam defects and affect the solidity of the steel structure.
2. Carry out anti-corrosion work. The temperature is low in winter, especially at large steel structure construction sites, where freezing will occur below zero. When welding connections, pay attention to keeping the welding surface dry and clean, and remove rust and stains. If there is frost on the interface surface, wipe it first. Work again after drying.
3. Preheating treatment. The preheating temperature is 20℃-50℃ higher than the conventional temperature. It is especially important to note that the preheating for positioning welding of thick plates is slightly higher than the formal welding. For welding with high heat input such as electroslag welding and submerged arc welding, The method can be the same as the conventional preheating temperature. For long components (generally larger than 10m), it is not recommended to evacuate the heating equipment (heating tube or electric heating sheet) during the welding process to prevent the situation of "one end is hot and the other is cold". For outdoor operations, thermal insulation and slow cooling measures should be taken for the weld area after welding is completed.
4. Welding should be carried out indoors as much as possible, and warning signs should be set up in areas with flammable, explosive and power distribution facilities. Check whether there are any flammable materials around, and ensure that the fire is extinguished before leaving get off work. Outdoor welding requires sheltering measures. Welding joints that have not yet been cooled must not be exposed to ice, snow or rain.
5. Welding equipment and precision instruments adopt special protection measures to prevent freezing, moisture-proofing and damage to equipment and instruments. Take effective measures to prevent electric shock in rainy and snowy weather, and use insulated gloves and insulated shoes.