7 Start up / Shut down
Operation manual mzr-2509 Ex/ mzr-2909 Ex / mzr-4609 Ex / mzr-7209 Ex
50
Technische Änderungen ohne Vorankündigung vorbehalten
Last update: October 2016
7.4
Operation of the micro annular gear pumps in different temperature ranges
Warning
Micro annular gear pumps are highly precise manufactured devices.
No
contamination
may reach the inside of the pump since this can damage the
pump. Make sure therefore, that all of the wetted parts are kept absolutely
free of dirt, dust or chips since this can affect the function of the pump.
Flow monitoring
is also required for operation in hazardous areas to securely
prevent dry running. If the flow stops, the pump must be stopped
immediately.
During operation in hazardous areas, particular attention must be paid to the
heat input in the liquid as well as to the increase of the pump’s surface
temperature. To avoid temperatures above a critical surface temperature one
of the following two measures has to be implemented (see 7.5). If the
specified top temperature is exceeded, the pump must stop immediately. For
the monitoring the compliance with standard EN 13463-6 has to be respected.
Remove dust deposits regularly from the pump’s surface, drive and connection
pipes so as to prevent the formation of ignition sources. The cleaning interval
must be determined by the level of dust precipitation by the operator.
The fluid connections mounted to the pump have to be checked immediately
after putting into service and following to this in a six month cycle on tightness
and leakage.
Monitor the operating sound of the pump. If grinding noise occurs, switch off
the pump immediately. Check the pump for wear optically. Friction between
metallic parts can lead to overheating or formation of sparks.
If the pump is used in hazardous areas, a flow sensor must be installed directly
downstream of the pump. The flow sensor must not create a noticeable back
pressure in case of damage. If the delivery rate of the pump falls to 20% of
the theoretical flow rate, the pump must be stopped immediately.
For operation of the micro annular gear pumps in surroundings with Ex-zone
request of temperature range T1-3 and T4 no additional temperature measure
is necessary for monitoring.
For operation of the micro annular gear pump in surroundings with Ex-zone
request of
temperature range T5 and T6 additional temperature monitoring
is
necessary.