Coborn PL Series

PL4/5i 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 minimize disc dishing.

The PL4i can be equipped with up to 5 work heads.

The larger PL5i can be equipped with up to 6 work heads.

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.

The lapping or polishing of the top surface of PCD or CVD components is desirable to produce a smooth surface for chip flow and a good cutting edge for geometric integrity. It also maximizes edge life, enhancing the characteristics of PCD and also minimizes surface deviations over a large PCD or CVD area.

The PL5i has a new user-friendly touchscreen control system providing more clarity on display status and more detailed diagnostics. New features include spindle load monitoring and the planetary wear indicator.