Pickling passivation (AP tube)

AP=Annealing (solid solution) + Pickling (pickling), the first letter AP of the two words represents two production processes. The pipe that has gone through the "solid solution, pickling" process is called AP pipe. Stainless steel AP pipe refers to a stainless steel pipe that has been pickled. Its corrosion resistance mainly comes from the reaction of the chromium element contained in it with oxygen to form a dense protective layer on its surface. The function of pickling is to make this reaction occur in advance to improve the corrosion resistance of stainless steel pipes. During the pickling process, the oil stains attached to the surface of the pipe and other substances contaminated during production will be removed.

BA (Bright Annealing) bright annealing

During the production process of stainless steel pipes, the grease particles used for lubrication may be deformed due to production and processing. In order to avoid residual grease in the stainless steel tube as much as possible, the annealing process uses high temperature and argon gas is used as the atmosphere in the furnace. By combining argon gas with carbon and oxygen to burn on the surface of the stainless steel pipe, the surface of the stainless steel pipe is further cleaned to create a bright effect. This method of heating and rapidly cooling with pure argon gas to make a smooth surface bright is called bright annealing. Although surface brightening in this way can keep the stainless steel pipe clean and free from any external contamination. However, if the brightness of this surface is compared with other polishing methods such as mechanical, chemical, and electrolysis, it will have a matte feel.

MP (Mechanical polishing) mechanical polishing

The polishing wheel or polishing belt uses the abrasives in the polishing agent to grind and polish the surface of the stainless steel pipe, thereby achieving a smooth and smooth polishing effect on the surface of the stainless steel pipe. Its brightness depends on the type of processing technology. Additionally, mechanical polishing, while more aesthetically pleasing, can also reduce corrosion resistance.

EP (Electro Polishing) electrolytic polishing

Electropolishing is an anodic treatment method. According to the principle of electrochemistry, proper adjustment of voltage, current, acid composition and polishing time can not only make the surface bright, smooth and clean, but also enhance the durability of the surface. It is corrosive, so surface brightening is a good method, but of course its cost and technology will also increase a lot.