Why do stainless steel heat exchange tubes need to be pickled?

There is a pickling process in the processing of stainless steel heat exchange tubes, which is to immerse them in an acidic solution. So why do we do this? What kind of effect can pickling bring to stainless steel heat exchange tubes?
There are three main reasons for pickling stainless steel heat exchange tubes:
1. Remove oxide scale/welding slag
The oxide scale and welding slag produced on the surface of stainless steel heat exchange tubes due to production and processing will affect their quality and corrosion resistance, which can be effectively removed by pickling to make the surface smoother.
2. Improve corrosion resistance
The chromium oxide film on the surface of stainless steel heat exchange tubes after pickling can be enhanced and repaired to improve corrosion resistance.
3. Improve appearance quality
The surface of stainless steel heat exchange tubes after pickling is bright and uniform, the color is consistent, and the appearance is beautiful, which is suitable for the decoration industry.
It can be seen that pickling is still a very important step for stainless steel heat exchange tubes. It is necessary to pickle and passivate stainless steel heat exchange tubes, not only to improve their performance and life, but also to ensure the safe and efficient operation of the system and meet relevant environmental protection and hygiene standards.