inded by the numeric-controlled grinder.
All the axles and rollers of the whole machine are made of high-quality steel and treated by tempering and grinding followed by high-precision computer dynamic balance rectification. They are all plated with rigid chrome and grinded surface.
All transmission gears are made by 20CrMnTi alloy steel, which is grinded after heat-treatment, rigidity HRC58-62, and which is made by rubbing, 6 grade precision to maintain high topping precision after long using.