Production process and application of straight seam pipe

Posted by chase Liu on June 26th, 2023

Straight seam steel pipe is a welded steel pipe in which the weld seam is parallel to the longitudinal direction of the steel pipe. It is usually divided into metric electric welded steel pipe, electric welded thin-walled pipe, transformer cooling oil pipe and so on. The production process of straight seam pipe is simple, the production efficiency is high, the cost is low, and the development is rapid. According to the production process, straight seam steel pipes can be divided into high frequency straight seam steel pipes (ERW pipes) and submerged arc welded straight seam steel pipes.

The strength of the spiral welded pipe is generally higher than that of the straight seam steel pipe. It can produce welded pipes with larger diameters with narrower billets, and welded pipes with different diameters can also be produced with the same width of billets. But compared with the straight seam pipe of the same length, the weld length is increased by 30~100%, and the production speed is lower. Welded pipes with large diameter or thicker diameters are generally directly made of steel billets, while small welded pipes and thin-walled welded pipes only need to be directly welded by steel strips. Then after a simple polishing, brushing on it. Therefore, most of the welded pipes with smaller diameters adopt straight seam welding, and most of the large diameter welded pipes adopt spiral welding.

Straight seam pipe process

Raw material decoiling—leveling—end cutting and welding—loop—forming—welding—removal of inner and outer welding beads—pre-calibration—induction heat treatment—sizing and straightening—eddy current testing— Cutting off—hydraulic inspection—pickling—final inspection (strict check)—packaging—delivery

This kind of steel pipe is welded by a welding method parallel to the longitudinal direction of the steel pipe, and it is also widely used. With the same diameter and length, the welding length of the straight seam pipe is much less, while the welding length of the spiral steel pipe may increase by more than 30%. Due to the process of welding, the efficiency is relatively low, and the output is also quite low. However, for the same blank, generally spiral welded pipes can obtain products of various diameters. In contrast, straight seam pipes cannot achieve this welding effect.

The reason why straight seam pipes are widely used in the market is because of their unique characteristics. Since the cost of the welding process is relatively low, and the production process of forged steel, extrusion, rolling and drawing steel can be manufactured, and the specifications are determined, it provides the possibility for a wide range of applications .

In my country, the petrochemical industry, tap water engineering industry, urban construction, electric power engineering, etc., all have demand for straight seam pipes.