Nordson VDK-MIDI TYPE 6, Operating Instructions Manual

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Type 6
7
E
2010
Gear Pump
Mounting of gear pumps
S
Before the gear pumps are installed, all lines should be rinsed by
flushing with Polymer or a similar medium. For flushing the lines use a
flushing--plate instead of the pumps.
S
Cylindrical screws used for mounting of the gear pumps must be of the
strength class 10.9 or 12.9. The thread of the screws should be coated
with a temperature stable lubricating medium prior to mounting.
(recommandation: OKS 240, Antiseize paste / Copper paste)
S
Heat up the pumps before mounting (pre--heating up to approximately
the operating temperature).
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Tighten the mounting screws cross--wise. For the drive torques see “Bolt
Tightening Torque” table in the operation manuals of the relevant
pumps. Use a torque wrench! Check the smooth rotation of the pumps
after mounting has been completed!
S
Pump heat insulation to be mounted over the pumps.
The gear pump should be protected from overloading with a suitable safety
device (shear pin) allowing a maximum of 90% of the permitted drive torque
(see respective gear pump specification).
Starting up of the plant
The temperature of the gear pumps must be that of the required standard
operating temperature before they are put into operation. The starting up
procedure should be according to recommendations as follows:
S
Before installing the gear pumps, all lines must be cleaned by flushing
with Polymer or similar. For flushing the lines use a flushing--plate
instead of the pumps.
S
Start up of the unit with disengaged pumps until the pre--pressure of the
gear pumps is approx. 20 -- 50 bar.
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In many cases, the pumps may start running already shortly after
starting the extruder. If all gear pumps are rotating slowly on their own,
skip the next two positions and start up.
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If the gear pumps are not running, shut down the unit and hold the
complete system at the normal operating temperature for a period of 2 –
3 hours. During this period, a temperature equalisation will be attained
between the beam and the pumps.
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After this time period, start the unit until the designated pre--pressure is
reached. With the help of the pre--pressure the disengaged gear pumps
will start to rotate slowly on their own.
S
Connect the driving shafts to the pumps and start up the motor units.