In polished stainless steel tube (201/202/304/304L/316/316L): within the weld leveling treatment, solution treatment, the inner surface of electrolytic polishing. For milk and food industry. The pharmaceutical industry. Fluid transport. Performance characteristics; inner surface roughness Ra up to 0.2 above, wall-less easy to clean residue and prevent bacterial growth, electrolytic polishing with ravioli of the role of inner anti-corrosion performance is good. Stainless steel tube inside the leveling (201/202/304/304L/316/316L): heat treatment after welding, which leveling. Pickling. Further pressure test. For the heater. Boilers. Heat exchangers, cold suspect device. Performance characteristics; canal wall smooth. Water resistance at the end, able to withstand high water flow rate of erosion. After solution treatment. Weld and basic mechanical properties. Basically the same corrosion resistance, processing and excellent performance. With "quality survival, reputation and development.