At what temperature can't steel structures be welded?

Problems needing attention in welding construction of steel structure;

1, welding has strict requirements on steel properties, and the steel used for welding steel structures should ensure the limit content of carbon.

2. For the matching of welding materials and parent materials, the strength of welding materials at the joint of materials should not be too different from that of parent materials.

3. Welding requirements for working environment, that is, windy days, rainy days, and low temperatures above Grade 4 shall not be welded. In this weather, the temperature of weld material drops rapidly after welding, and it is easy to produce large residual stress or deformation at the weld, and even cracks.

In the welding process, the workpiece and solder melt to form a melting zone, and the molten pool cools and solidifies to form a connection between materials. In this process, pressure is usually needed. There are many sources of welding energy, including gas flame, arc, laser, electron beam, friction and ultrasound.

Extended data:

When welding, both sides of the weld will be affected by welding heat, and the structure and properties will change. This area is called the heat affected zone. When welding, the workpiece material, welding material and welding current are different.

It is necessary to adjust welding conditions to deteriorate solderability. Preheating, temperature maintenance during welding and post-welding heat treatment can improve the welding quality of weldments.

The cross-sectional shape of butt weld depends on the thickness of the welded body before welding and the groove form of the two edges. When welding thick steel plates, grooves of various shapes are made at the joints for penetration, so that covered electrode or welding wire can be easily fed.

Groove forms include single-sided welding groove and double-sided welding groove. When choosing the groove form, in addition to ensuring the penetration depth, factors such as convenient welding, less metal filling, small welding deformation and low groove processing cost should also be considered.

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