SKF MKU Series User Manual

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5
EN
5. Functional description
Gear pump units without an integrated
electronic control unit are controlled by the
control unit of the machine to which the
gear pump unit is connected. The machine
control unit controls the pump cycle time,
the pump delay time, and the interval time
of the gear pump unit according to the
lubricant required by the lubrication points.
The pump cycle time, referred to as the
contact time, consists of the pressure build-
up time and the pump delay time.
The monitoring time consists of the period
between switching on the gear pump motor
and establishment of the maximum pressure
built-up time. A fault signal will be issued if
the maximum pressure build-up time elapses
without the pressure switch closing.
The interval time is the period between two
pump cycle times (contact time).
A lubricating cycle consists of the contact
time and the interval time.
Operating mode S3 of the gear pump
motor is used to define the interval time, the
pump cycle time, and the pump delay time.
5.3 Gear pump unit without control unit
Consult the “Technical data” chapter for in-
formation on the operating mode.
With regard to monitoring pressure build-up
in the main lubricant line during a lubricating
cycle, note that several seconds may pass
after the gear pump motor is switched on
before the pressure switch responds. A
fixed monitoring time for lubricant pressure
build-up is recommended so that the machine
control unit waits until this time has elapsed
to issue a fault notification if the required
lubricant pressure is not reached. A period
of approx. 60 seconds is recommended. The
pressure switch responds once the required
lubricant pressure has been reached. If the
required lubricant pressure is not reached,
the machine must be shut down to prevent
underlubrication of the bearings.
To prevent underlubrication of the bearings
in the oil +air pump design (MKL without
control unit), the monitoring of minimum
air pressure of the supplied compressed air
must be configured so that the machine is
shut down if there is no air pressure or the
pressure drops too low. Ensure that a time
buffer is stored in the machine control unit
to level out brief pressure fluctuations in the
compressed air supply.
In order to prevent underlubrication of
the bearings, monitoring of the minimum
fill level of the lubricant reservoir must be
configured in such a way that the machine is
shut down if the fill level is too low.

SKF MKU Series Specifications

General

Brand	SKF
Model	MKU Series
Category	Water Pump
Language	English