pre-coat filter

ThePre-Coat filter is used when a fine clarity is required. This may befor Honing, Lapping, Boring, Deep hole drilling or Super-finishing.Clarity of less than 5 micron is possible using a pre-coat powder suchas Cellulose Fibre or Diatomaceous Earth. There are five or six maincomponents to the system.

Conveyorised tank.
Thedirty coolant from the machines is discharged into the dirtyconveyorised tank. Settlement takes place, and the heavy fines willsettle at the base of the tank and be discharged by the flight barconveyor. The coolant oil will then be transferred  to the Pre-Coatvessel by the Filter pumps, where the fines are removed and the cleancoolant discharges into a Clean tank.

Clean Tank.
The clean tank is usually located adjacent to the dirty tank.  The tank will always be full and overflowing intothe dirty tank. This tank can be temperature controlled, as is normallythe requirement for fine filtration. The system pumps will thentransfer the clean coolant to the machines.

Slurry preparation tank.
Aslurry tank and combined powder hopper, work together to form a slurryof Coolant/oil and Cellulose Fibre. The slurry is then pumped into thePre-Coat filter vessel, to support the pre-coat cycle. This cycle isrequired every time the filter differential pressure is reached.

Waste conveyor.
Atank with flight bar conveyor which allows settlement of fines whichare then discharged at the elevated neck of the tank. It is normal touse a needle felt filter in the base to ensure the fines are removed.