What is AP grade, MP grade stainless steel pipe?

AP (Acid Pickling)

The corrosion resistance of stainless steel mainly comes from the formation of a dense protective layer on its surface after the chromium element in it reacts with oxygen. The role of pickling is to make it happen in advance of this reaction, in order to improve the corrosion resistance of stainless steel pipe, pickling process will remove the oil attached to the surface of the pipe and other substances contaminated in the production. The inner and outer surface of the pipeline is rough and easy to be attached by suspended impurities.

MP (Mechanical polishing)

Polishing wheel or polishing belt with the abrasive in the polishing agent to polish the surface of stainless steel tube, so that the stainless steel tube surface to achieve smooth polishing effect. Its brightness and effect depends on the type of processing method. In addition, although the mechanical polishing is more beautiful, it will also reduce the corrosion resistance, so when used in the corrosive environment, it needs to be passivated, and the surface of the steel pipe is often polished material residue.