Solutions

The task

State-of-the-art machining processes require pump pressure values clearly above 15 bar, like in deep hole drilling,
grinding with CBN wheels or in wire-EDM machining.

Forced circulation-type high pressure pumps are offered on the market, like e.g. screw-spindle pumps or gear pumps. These pump systems are sensitive to pollution and impurities and usually clearly more expensive than conventional centrifugal coolant pumps.

Varying machining processes and different tools often require retrofitting to higher pressure ranges.
In already existing coolant systems, provisions shall be made to connect pressure increasing units, generally or according to the circumstances.

The solution

Increasing pressures by centrifugal pumps: By combining two BRINKMANN centrifugal pumps arranged in tandem, pressures of over 50 bar can be attained.

Here, the immersion pump delivers a pressure of up to 26 bar (load capacity limit of the rotating mechanical seal). It delivers into a pressure increasing pump with the inlet flange being directly above the rotating mechanical seal, so that the pumping unit located below can produce a pressure of additional 26 bars.

Another application of pressure increasing pumps is to be found with coolant systems in which the pressure increasing pump is charged with an inlet pressure from the central system.

Note:

Switch on pressure increasing pumps with time delay (pressure increasing pumps must be connected only if the medium is at the pressure joint). the use of slow closing valves is recommended.

Technical information

Tandem arrangements of coolant pumps are suitable for realizing further working points also if 4-2 change-pole motors or frequency converters are used.