There are two main polishing techniques, one is chemical polishing and the other is electrolytic polishing.
- Chemical polishing
This method is commonly used in the surface treatment process of seamless steel pipes. It does not require DC power supply and special fixtures. It can polish parts with complex shapes and has high productivity. Chemical polishing can obtain a surface with physical and chemical cleanliness, and can also remove the mechanical damage layer and stress layer on the surface of the seamless steel pipe to obtain a surface with mechanical cleanliness, which is beneficial to prevent local corrosion of parts, improve mechanical strength, and prolong the use of parts. Because there are many varieties of seamless steel pipes, and different grades of seamless steel pipes have different corrosion laws, there are many types of chemical polishing solutions for seamless steel pipes, and the basic components include corrosives, oxidants and water. Corrosive agent is the main ingredient, if the seamless steel pipe is dissolved in the solution, the polishing cannot be carried out. Oxidants and additives can inhibit the process, allowing the reaction to proceed in a direction that favours polishing. Water regulates the concentration of the solution and facilitates the diffusion of reaction products.
- Electropolishing of seamless steel pipe
This method is to hang the seamless steel pipe product on the anode, and carry out the anode electrolytic processing in the electrolytic polishing solution. During electropolishing, two contradictory processes are carried out on the surface of seamless steel pipe products at the same time, that is, the continuous formation and dissolution of the oxide film on the metal surface. Due to the different current density distribution, the surface of the product is continuously formed and dissolved at different rates. The anode surface is undergoing two opposite processes at the same time, film formation and dissolution, and the continuous formation and dissolution of the passive film, so that the surface of the seamless steel pipe product is leveled to achieve a highly smooth and glossy appearance, which meets the requirements of the seamless steel pipe product. Table blood polished for finishing purposes.