... tube, oval tube, fan-shaped tube, polygonal tube, single and double groove pipe, tube frame, special-shaped mould, etc.3. ... turning- CNC precision turning- grinding- quenching- hardness test- internal and external grinding- test- boxing.10. Features: Mature manufacturing process, ... , mechanical pattern, on the corner, concave angle phenomena, and to form tolerance of roundness in les than 0.05mm ...