Coborn PL Series

Planetary Lapping Machines for PCD

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 PL4 is equipped with 4 work heads and a fifth work head can be fitted as an optional extra.

The larger 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.