The difference between straight steel pipe and seamless steel pipe

The difference between straight steel pipe and seamless steel pipe

Straight seam steel pipe and seamless steel pipe have significant differences in manufacturing process, application scenario, performance and so on.

1. Manufacturing process

Straight seam steel pipe is made by crimping steel plate or steel strip and welding along the longitudinal. And according to the different Welding methods, straight Welded steel pipes can be divided into ERW (Electric Resistance Welded) and LSAW (Longitudinal Submerged Arc Welding) two kinds. The main use of welding process molding, by heating the two sides of the steel to weld the two sides of the steel to form a straight weld.
Seamless steel pipes are directly produced by hot rolling, cold rolling or cold drawing processes, and there are no welds. In the production process, the solid billet is stretched into a tube using a perforator, and it is hot or cold rolled several times to make it have a high precision and uniform inner wall.

2. Performance characteristics

Straight steel pipe: Because it is a welded steel pipe, the strength of the weld is lower than the strength of the pipe wall, especially in high pressure places, the existence of the weld will affect the normal work of the pipeline. However, because of its fast production speed and low cost, it has better cost-effective and stability in low and medium pressure and non-high temperature environments.
Seamless steel pipe: no weld, with uniform mechanical properties, and excellent compressive and tensile properties, suitable for high temperature and high pressure, corrosive occasions, such as petroleum, chemical and boiler industries. However, due to its relatively complex production process, the cost is higher, but its strength and performance are also more excellent.

3. Scope of application

Straight steel pipe: suitable for the transportation of medium and low pressure fluids, such as water, natural gas, air, and oil. Widely used in building structures, such as support pipes, scaffolding and so on.
Seamless steel pipe: suitable for high temperature, high pressure environment, such as boiler tubes, pressure vessels, oil and gas industry. It performs well in the transportation of liquids, gases and vapors and is suitable for high-pressure environments.

In summary:

In general, the difference between straight steel pipes and seamless steel pipes is mainly in the manufacturing process, because of the difference in their production process, making their performance different. Straight steel pipes are suitable for working in medium and low pressure and non-high temperature environments, while seamless pipes are suitable for use in high temperature and high pressure or harsh environments. In the selection of materials, the pressure, temperature, environment and other factors should be considered comprehensively, and the appropriate pipe should be applied to cope with the corresponding environment.