Richter V&A RMI Series, Инструкция по установке и эксплуатации

Страница: 15 / 36

Series RMI
Page 15
9430-050-en Revision 00
TM 9886 Edition 03/2018
6.3 Shutdown
♦ Close discharge valve down to the position "mini-
mum flow rate"
♦ Switch motor off.
♦ Close discharge valve completely.
Only close the suction line if the pump is to be evacu-
ated or dismantled.
For all work on the machine, make sure that
the motor cannot be inadvertently switched
on.
If the pump is to be evacuated or flushed,
observe the local regulations.
If the pump has been operated with a
chargeable liquid, it must be filled with inert
gas (e.g. nitrogen) to prevent an explosive
atmosphere.
It is recommended to wait one hour before the pump
is dismantled from the plant to permit static peak
charges to be eliminated.
If the pump is returned to the manufacturer's, clean
the pump very thoroughly.
See also
Section 3.1
.
6.4 Restarting
When the pump is restarted, it must be ensured that
all the relative steps as described in Section 6.1 are
repeated, depending on the progress of the shutdown
operation.
6.5 Improper operations and their
consequences (examples)
Inadmissible modes of operation, even for
brief periods, may result in serious damage
to the unit.
In connection with explosion protection, potential
sources of ignition (overheating, electrostatic and
induced charges, mechanical and electric sparks)
may result from these inadmissible modes of
operation; their occurrence can only be prevented by
adhering to the intended use.
Operation with magnetic drive stopped:
♦ If no heat is dissipated, damage to the impeller
and drive magnet assembly may occur.
Pump is started up without medium :
♦ The plain bearings in the pump may be de-
stroyed.
♦ Other pump components may be destroyed due
to overheating.
Suction line not opened or not opened fully :
♦ Pump is cavitating – material damage to pump
and plain bearings
♦ Pump does not attain the required delivery head
or flow rate.
♦ Pump may be destroyed due to overheating.
Discharge valve closed too much :
♦ Pump may be destroyed due to overheating.
♦ Axial thrust too great.
Discharge valve opened too much :
♦ Pump can cavitate. Particularly severe with an
empty discharge line.
♦ Risk of pressure surge.
♦ Possible damage to the plain bearings.
♦ Magnetic drive may stop.
♦ Motor may be overloaded.
Suction valve and discharge valve closed :
♦ Destruction due to rapid overheating and sharp
rise in pressure.
Control of the pump with the suction valve :
♦ Cavitation – the volume may only be regulated on
the discharge side.
Overrun of the admissible gas content:
♦ The flow may stop.
♦ Switch pump and vent off for renewed convey-
ance.
♦ Make sure that the gas content is not exceeded,
as described in the intended use.