What's the difference between straight seam steel pipe and spiral steel pipe?
In the steel pipe manufacturing industry, straight-seam steel pipes and spiral steel pipes are very common. Although both of them have welds, they show significant differences in many aspects.
Let's talk about the production process first. Straight-seam steel pipe is to bend strip steel or steel plate directly into a pipe shape and then weld it along the longitudinal direction of the pipe, so the weld is a straight line. Its production process is not complicated, and the commonly used welding methods are high frequency resistance welding and submerged arc welding. High-frequency resistance welding relies on high-frequency current, which can make the edges of steel pipes heat and fuse together quickly, and the production efficiency is particularly high. Submerged arc welding can make high-quality welds and is suitable for welding thick-walled straight-seam steel pipes. The practice of spiral steel pipe is to roll the strip steel into a tube according to a certain spiral angle and then weld it. The weld is spiral. This method can continuously produce large-diameter steel pipes, mainly using double-sided submerged arc welding, which is fast and of good quality.
Let's talk about performance characteristics again. The weld seam of straight seam steel pipe is short, and the welding quality is better controlled. However, because the welds are all in a straight line, the stress distribution is not as uniform as that of spiral steel pipe, and the bending capacity and overall strength are relatively weak. The weld of spiral steel pipe is spirally distributed, which can disperse the axial stress, so it has stronger ability to resist external pressure and deformation, and is more stable under various complex stress conditions.
Finally, look at the application scenario. Straight-seam steel pipes have high precision, and are often used in the fields of building structures and machinery manufacturing, such as steel structure frames for building houses and mechanical parts manufacturing. Spiral steel pipe has strong pressure bearing capacity, and is especially used in the construction of long-distance transportation pipelines such as oil and natural gas, which can ensure safe and stable transportation in high-pressure environment.
These two kinds of steel pipes have their own advantages, so when they are used in practice, they should be selected according to specific needs.
