What are the surface defects in 5310 high-pressure boiler tubes

5310 high-pressure boiler tubes refer to steel tubes that are open at both ends and have a hollow cross-section, with a large length-to-circumference ratio. They can be classified into seamless steel pipes and welded steel pipes according to their production methods. The specifications of 5310 high-pressure boiler tubes are expressed by their external dimensions (such as outer diameter or side length) and wall thickness. The size range of 5310 high-pressure boiler tubes is very wide, from very small diameter capillary tubes to large diameter pipes with diameters of several meters. 5310 high-pressure boiler tubes can be used in pipelines, thermal equipment, machinery industry, petroleum geological exploration, containers, chemical industry, and special applications.

5310 high-pressure boiler tubes may encounter a series of problems during normal use. Standards specify a "smooth surface" requirement for 5310 high-pressure boiler tubes. However, due to various reasons during the production process, there are as many as a dozen surface defects in 5310 high-pressure boiler tubes. These defects in 5310 high-pressure boiler tubes include: surface cracks (fissures), hairline cracks, internal folds, external folds, punctures, internal straight lines, external straight lines, delamination, scars, pits, bulges, rough surfaces (pits), scratches, internal spiral lines, external spiral lines, blue lines, straightening dents, and roll marks.

These defects in 5310 high-pressure boiler tubes are primarily caused by surface or internal defects in the tube blank. Secondly, they arise during the production process. For example, improper rolling process parameters, rough tool surfaces, poor lubrication, and improper die design and adjustment can all lead to surface quality problems. Alternatively, during heating, rolling, heat treatment, and straightening, excessive residual stress can occur due to improper temperature control, uneven deformation, unreasonable heating and cooling rates, or excessive straightening deformation, which can also cause surface cracks in the 5310 high-pressure boiler tube.