What is the difference between stainless steel heat exchange tubes and stainless steel seamless tubes? The differences between the two are mainly reflected in manufacturing processes, performance characteristics, and application scenarios.
In terms of manufacturing process, stainless steel heat exchange tubes can be manufactured through welded pipe or seamless pipe process, using cold-rolled stainless steel strips (welded pipes) or round steel ingots (seamless pipes) as raw materials. Welded pipes have longitudinal welds, while seamless pipes have no welds; Stainless steel seamless pipes are only formed by hot/cold rolling perforation without any welds. The raw material is made of solid steel billets perforated without any welds.
In terms of performance and quality, in terms of wall thickness uniformity, stainless steel heat exchange welded pipes are made of cold-rolled steel plates with small wall thickness tolerances (± 0.02mm) and smooth inner walls that are not prone to scaling; Stainless steel seamless pipes have uneven wall thickness (deviation>10%) due to perforation process, and the inner wall is prone to residual pitting and black spots. In terms of mechanical properties, stainless steel seamless pipes with the same material have higher compressive strength (without weak weld zones), with a pressure limit of>5MPa. However, modern welded pipes can achieve a weld strength of up to 90% of the base material, partially replacing seamless pipes. In terms of corrosion resistance, if the heat treatment of stainless steel heat exchange welded pipes is improper, the weld area is prone to become a weak point of corrosion; Stainless steel seamless pipes have uniform corrosion resistance and are suitable for highly corrosive media.
In terms of cost, stainless steel heat exchange welded pipes have low cost and are suitable for mass production. They have high production efficiency, can be customized to any length, and have high precision; Stainless steel seamless pipes, on the other hand, have complex processes, low yield rates, high costs, slow production speed due to single roll rolling, high fixed length costs, and significant waste of excess materials.
Therefore, for low-pressure fluids, high anti scaling requirements, and cost sensitive projects, stainless steel heat exchange welded pipes are preferred. Seamless pipes must be used for high-pressure and high-temperature systems, nuclear power, aviation, and transportation of strong acid and alkali media.