When welding thick steel plates above 9mm under negative temperature, double-layer welding should be used. The welding is sprayed from bottom to top, and each welding is welded once, such as welding infix, before welding again. It is forbidden to start the arc on the original welding material. When the steel structure is installed on the spot, if it snows or the wind is above 6m/s, erect a protective shed.

But the closed welding completely eliminates rewelding, and the welding is stopped according to the standard of the welding process of steel structure under negative temperature. When the working temperature is less than 0℃, the coating process test is carried out in the coating of anti-corrosion materials. The rust, oil stains, burrs and other things on the surface of the component must be cleaned up during the coating, and the surface must be dull and boring. Do not stop painting work when it is snowing or there is thin ice on the components.

When transporting and stacking steel structures in winter, the ground anti-skid countermeasures are adopted. The components are stacked and leveled. The site is firm and has no puddles, and there is no freezing in the sky. When the components of the same type and specifications are stacked, the components should be kept level and the pads should be placed on the same straight line to prevent the components from slipping. According to the requirements of the negative temperature standard before the steel structure installation, the quality of the steel structure shall be re-inspected, and the components that have been deformed during the manufacturing process and the transportation and accumulation shall be repaired and corrected in mid-air.

When using steel cables to lift steel components, it is necessary to add anti-skid spacers on the ground, and the connection point plates that are hoisted with the components at the same time, and the fixtures used by the installation staff are tightly tied with rope locks. According to the general data chart of the temperature standard non-staff steel component installation, the installation shall be stopped strictly according to the standard general theory during the construction of the project. The welding process of the custom-made steel structure device, the two sides of a component can not stop welding at the same time.