Material selection for heat exchangers depends on specific operating conditions. The following outlines objective differences between stainless steel welded tubes and copper tubes across several key aspects.
1.Thermal Conductivity
Copper has higher thermal conductivity than stainless steel.
Stainless steel has lower thermal conductivity than copper.
2.Corrosion Resistance
316L stainless steel exhibits better corrosion resistance in chloride‑containing, acidic, or oxidizing media.
Copper exhibits better corrosion resistance in certain media (e.g., ammonia, deaerated non‑acidic water), but may suffer pitting or erosion in chloride‑containing, ammonia‑containing, or high‑velocity water.
3.Mechanical Strength
Stainless steel has higher yield strength and tensile strength than copper.
Copper has lower yield strength and tensile strength than stainless steel.
4.Inner Surface and Scaling Tendency
Stainless steel has a dense surface that is less prone to forming loose scale layers under certain water conditions.
Copper tubes may develop scale layers on the inner surface under certain water conditions, depending on water chemistry.
5.Wall Thickness Design
Under the same pressure requirement, stainless steel can be designed with a thinner wall thickness than copper.
Copper typically requires a thicker wall thickness than stainless steel under the same pressure requirement.
（The above comparison provides qualitative descriptions of material properties only. Final material selection should be based on actual operating conditions (medium composition, temperature, pressure, flow velocity, service life requirements, etc.) and consultation with materials or equipment professionals.）
