Coborn Engineering Co Ltd

PL4-5 - PLANETARY LAPPING MACHINE FOR PCD

PL4/5

Coborn’s planetary lapping machines are designed to polish the top surface of PCD discs to a flat, mirror finish. They can also be used to polish CVD discs and PcBN. The machine consists of a number of independent work heads which hold the discs against a large, horizontally mounted planetary motion grinding wheel.It is impossible to use flood cooling when polishing large areas of PCD as the discs ‘aqua-plane’ on the wheel surface. Therefore, the lapping is a dry process and the wheel is internally cooled using water from an associated water chiller.Chilled water is also fed to the back of each disc. This maintains the disc at a uniform temperature to minimise disc dishing. The PL5 is equipped with 6 work heads as standard. Each arm is fitted with a double gimbal fixture to allow the disc to self-level. The disc holders are motor driven. The lapping pressure can be individually adjusted.