What disadvantages may occur when steel structures are welded? steel structure

What are the possible disadvantages of welded steel structures? Steel structure company

Steel structure is a popular metal material in recent years. This material is widely used in the construction industry to make workshops and floors. What are the disadvantages of structural welding? Let's have a look at it with the steel structure company.

1. Thermal cracks

Its basic feature is that it occurs in the process of welding cooling. The primary reason is that sulfur and phosphorus impurities in steel or welding materials form various brittle and hard low-melting eutectic crystals with steel. During the cooling process of welding, the finally condensed low-melting eutectic is in a tensile state, which is very easy to crack.

Second, cold cracks

Cold cracks that occur in welding, also known as delayed Cracks, delayed characteristics appear minutes to days after welding. The primary reason is closely related to the selection of steel, the design of the structure, the storage and use of welding materials, and the welding process.

3. Laminar tearing

The main feature of the steel structure company is the low alloy high strength steel, the thickness is large, The impurity content is high, the sulfur content is high, and the segregation is violent along the parallel direction of sheet rolling. When the Hebei steel structure is subjected to a force perpendicular to the thickness direction during the welding process, cracks that step along the rolling direction will occur.

Fourth, lack of fusion and lack of penetration

The reasons for both are basically the same, mainly due to process parameters, methods Inappropriate size of grooves, insufficient cleaning of grooves and weld surfaces or impurities such as welding slag and welding slag, poor welder skills.

V. Stomata

According to its production form, it can be divided into two types: deposition pores and active pores. The deposited pores are mainly hydrogen pores and nitrogen pores. The primary feature of deposition pores is surface pores. The primary difference between hydrogen pores and nitrogen pores is that hydrogen pores are mainly composed of single pores, while nitrogen pores are mainly fine pores. The primary reasons for pores in the weld are related to the selection, preservation and use of welding materials, the selection of welding process parameters, the degree of cleanliness of the groove base metal and the degree of protection of the molten pool.