The appearance of pits and air holes on the surface of honed tube is specially related to the material itself, which should be avoided. Further treatment should be taken to prevent such defects during processing.
As a grinding of high precision, the product can not only work on the hole (mostly), but also on the quenched surface of tooth. As a matter of fact, it’s a kind of polishing, and featuring integration of different grinding tools and fixture onto floating clamp, it can make fine self-regulation. So the shape error of hole can be prevented, but not the error of shape and position. On the other hand, when polishing a honed tube with thick wall, it’s usually with soft polisher wheel or round polisher disc，together with polisher paste (a polishing material), by which the work piece can be processed precisely with high surface finish. Nevertheless, because of lack of rigid reference surface during processing, error of shape and position can’t be eliminated. Stainless steel honed tubes with irregular surface can also be polished.
https://www.ht-tube.com/