High-pressure boiler steel pipes refer to steel pipes that are open at both ends and have a hollow cross-section. The length-to-circumference ratio of high-pressure boiler steel pipes is relatively large. According to the production method, they can be divided into seamless steel pipes and welded steel pipes. The specifications of high-pressure boiler steel pipes are expressed by their external dimensions (such as outer diameter or side length) and wall thickness. The size range of high-pressure boiler steel pipes is very wide, from very small diameter capillary tubes to large diameter pipes with diameters of several meters. High-pressure boiler steel pipes can be used in pipelines, thermal equipment, the machinery industry, petroleum geological exploration, containers, the chemical industry, and special applications.
High-pressure boiler steel pipes may encounter a series of problems during normal use. Standards specify the requirement of a “smooth surface” for steel pipes. However, due to various reasons during the production process, there are as many as a dozen types of surface defects in steel pipes. Common surface defects in high-pressure boiler steel pipes include: surface cracks, hairline cracks, internal folds, external folds, punctures, internal straight lines, external straight lines, delamination, scabs, pits, bulges, pitting, scratches, internal spiral lines, external spiral lines, blue lines, straightening dents, and roll marks.
The causes of these defects in high-pressure boiler steel pipes are primarily twofold: firstly, they arise from surface or internal defects in the pipe blank; secondly, they occur during the production process. Specifically, improper rolling process parameters, rough tool surfaces, poor lubrication, and improper die design and adjustment can all lead to surface quality problems. Alternatively, during the heating, rolling, heat treatment, and straightening processes, excessive residual stress due to improper temperature control, uneven deformation, unreasonable heating and cooling rates, or excessive straightening deformation can also cause surface cracks in the high-pressure boiler steel pipe.
Post time: Mar-18-2026