Classification methods and basic types of welded pipe welded joints

Classification methods and basic types of welded pipe welded joints

The types of welded joints include butt joint, T-joint, lap joint and corner joint. The welded joints are mainly selected according to the welding structure, weld thickness, weld strength requirements and construction conditions.

Function of welded joint:

Butt joint, with uniform force, high strength, smooth appearance and beautiful appearance, is widely used. However, the preparation and assembly requirements before welding are high. The preparation of lap joint is simple before welding, but the additional bending stress will reduce the strength. Fillet joint usually only plays a connecting role, which is used to transmit the working load. T-joint is used for space welding parts with high strength.

Function of welding groove

The edge of the metal material is processed into a groove, and the ratio of the base metal and the filler metal is adjusted, so that the thick weldment can be welded through.

Classification and basic types of welded joints

1.Classification method of welded joint

The welded joint is composed of weld, fusion zone, heat affected zone and its adjacent base metal. The welded joint mainly plays two roles, one is connection, the other is force transmission.

2.Basic types of welded joints

According to different welding methods, welded joints can be divided into three categories: fusion welded joint, pressure welded joint and brazed joint. The basic types of welded joints can be summarized as butt joint, lap joint, T-joint, end joint and corner joint.

The above five basic types of joints are suitable for fusion welding. Generally, lap joints are used for pressure welding, and butt joints are used in some cases. Butt joints are generally used for high frequency resistance welding, and lap joints are only used in some cases.

Fusion welded joint and groove

Butt joint is an ideal joint form in fusion welding. The edge of weldment is processed into various types of groove for butt welding, which can ensure welding quality and reduce welding deformation and welding material consumption.

According to the different shapes of welded joints, groove can be divided into three types: basic type, mixed type and special type.

The basic groove mainly includes I-shaped groove, unilateral V-shaped groove, V-shaped groove, J-shaped groove, U-shaped groove, etc.

Special groove mainly includes curling groove, locking groove, groove with backing plate, etc.

Selection principle of welded joint

Ensure that the joints meet the requirements; Welding difficulty and welding deformation; The manufacturing and construction unit shall have the technical, personnel and equipment conditions required for construction.