High frequency straight seam welded pipe processing procedure

The specific method of checking the high-frequency straight seam welded pipe is that such non-fusion is generally reflected in the failure of the pressing process, the crack of the steel pipe during the hydraulic test, or the crack of the welding gap when the steel pipe is straightened, which is a more serious defect.

In addition, the welding heat input will also be affected by the quality of the strip edge, such as the strip edge burr phenomenon, before entering the extrusion roll solder joint burr phenomenon will cause ignition, resulting in welding power damage and heat input reduction, resulting in non-fusion or cold welding

The main parameters of high frequency straight seam welded pipe

Welding pressure is one of the main parameters of welding technology. After the edge of the strip is heated to the welding temperature, the metal atoms are combined with each other under the extrusion pressure of the extrusion roll to produce welding gaps. The size of the welding pressure interferes with the strength and toughness of the welding gap.

If the increased welding pressure is too small, the welding edge cannot be fully fused, and the residual metal oxides in the welding gap cannot be discharged and cause inclusion, resulting in a significant reduction in the tensile strength of the welding gap, and the welding gap is easy to crack after being stressed

Welding rate is also one of the main parameters of welding technology, which is related to the heating system, the deformation rate of welding gap and the rate of metal atom crystallization.

For high-frequency welding, the welding quality is improved with the acceleration of welding rate, because the decrease of heating time makes the width of the edge heating zone smaller and reduces the time of metal oxide generation

The opening Angle, also known as the welding V Angle, refers to the Angle between the edge of the extrusion roll, the general opening Angle varies between 3° and 6°, and the size of the opening Angle is mainly determined by the location of the guide roller and the thickness of the guide sheet.

After the post-welding process, there is also a heat treatment process to eliminate the internal stress in the welding gap and thermal interference zone, refine the grain size, and strengthen the mechanical properties. Make full use of and expand this main advantage, can improve product quality and open up the market of products.