Fully Automatic Precoat Filter VDP ASF 500.240

Task:

Supply of 500 l/min finely filtered cutting oil for a grinding machine that produces screw pump rotors made of cast iron. A filter fineness of 5 µm is required for preventing an accumulation of graphite. Supply of oil for the grinding spindle and the hydraulic system is also provided by using filtered cutting oil.

A further goal is to minimize the consumption of filter consumables, precise temperature regulation of the cutting oil and effective, reliable extraction of substances from the machining areas.

Key data:
Coolant:	Cutting oil with a kinematic viscosity of 15 cSt at 40°C
Machining process:	Grinding of rotors for screw pumps, roughing and smoothing
Material:	Cast iron
Tools:	Galvanic CBN grinding disks, B 151 - B 251
Impurity removal rate:	6 kg/h

Design:

A fully automatic precoat filter, model VDP ASF 500.240, with two, alternating-duty, filter vessels is employed. A four-stage magnetic separator is used for preliminary separation of coarse ferritic particles and for considerably enhancing the cycle time of the precoat filter vessels.

Fully automatic operation of the filter ensures continuous supply of cleansed oil to the grinding machine.

Results:

Use of filtration aids is minimized through the effective use of a multiple-stage magnetic separator. The machining oil that is filtered by the HOFFMANN precoat filter prevents the accumulation of very fine particles. The guide paths and other movable components of the machine tool are protected and the fabricated parts remain free of adherent residual soiling.

Oil mist that accumulates in the HOFFMANN mist collector is routed back into the oil system. There, multiple-stage pre-filtering elements prevent premature saturation of the high-efficiency filter elements. Optimal utilization of the filter elements is achieved with the aid of differential pressure indicators.

One control cabinet for all HOFFMANN components (filters, chillers, Mist collectors) provides the customer with a clear overview of the filter's processes.