Mechanical polishing internal surface polishing (use internal polishing machine): use the throwing rod to extend into the tube to drive the impeller or the self-made abrasive belt wheel to rotate at high speed, and polish with the rotation of the stainless steel welded pipe itself, and slowly advance the throwing rod while rotating. Generally speaking, first use the 60 # -80 # impeller or abrasive belt wheel for coarse polishing, and then gradually perform fine polishing with high precision according to the requirements of smoothness. Large-sized tubes 6 "and above generally use the impeller, small-sized tubes can use self-made abrasive belt wheels, which can reduce costs. If mechanical polishing throws are not bright enough, you can properly apply polishing paste to increase the shine when fine throwing.
Electrolytic polishing Electropolishing uses the thrown workpiece as the anode and the insoluble metal as the cathode. Both poles are immersed in the electrolytic cell at the same time, and direct current is applied to produce selective anode dissolution, thereby achieving the effect of increasing the brightness of the workpiece surface. Specifically, you can know by searching "what is electrolytic polishing"! After polishing, because the surface oxide layer is damaged, the surface should be passivated with acid, otherwise it will easily rust