The processing specifications for wrapped finned tubes cover key aspects such as material handling, winding process, welding control, and quality inspection. The specific technical standards are as follows:
1. Material selection for pipes and fins
Pipe material: 20 # carbon steel seamless pipe is used for high temperature and high pressure environments, and 304/316L stainless steel pipe is selected for corrosion-resistant scenarios; Wall thickness tolerance ± 10%, outer diameter deviation ≤ 0.3mm.
Fin strip: commonly used aluminum strip (0.3mm thick) or steel strip (0.8-1mm thick ± 0.05mm), with a width determined by the design (such as 20mm ± 0.3mm), and a smooth and burr free surface.
2. Surface treatment
Shot blasting and rust removal of carbon steel pipes (speed 80m/s), acid pickling and passivation of stainless steel pipes (soaking in 10% nitric acid solution for 15 minutes).
Fin strip leveling treatment, with a flatness error of ≤± 0.5mm/m, and no burrs on the edges after cutting.