Speck pumpen Normblock - 8 Trouble-shooting

8 Trouble-shooting
WARNING
Improper work to remedy faults
Risk of injury!
▷ For any work to remedy faults observe the relevant information in this manual
or in the relevant accessory manufacturer's product literature.
If problems occur that are not described in the following table, consultation with the
customer service is required.
Pump delivers insufficient flow rate
Motor is overloaded
Excessive discharge pressure
Increased bearing temperature
Leakage at the pump
Excessive leakage at the shaft seal
Vibrations during pump operation
Impermissible temperature increase in the pump
Table 19: Trouble-shooting
A B C D E F G H Possible cause
Remedy
5)
✘ - - - - - - - Pump delivers against an excessively
high pressure.
Re-adjust to duty point.
Check system for impurities.
Fit a larger impeller.
6)
Increase the speed (turbine, I.C. engine).
✘ - - - - - ✘ ✘ Pump or piping are not completely
vented or primed.
Vent and/or prime.
✘ - - - - - - - Supply line or impeller clogged Remove deposits in the pump and/or piping.
✘ - - - - - - - Formation of air pockets in the piping Alter piping layout.
Fit vent valve.
✘ - - - - - ✘ ✘ Suction lift is too high/NPSHavailable
(positive suction head) is too low.
Check/alter fluid level.
Install pump at a lower level.
Fully open the shut-off element in the suction
line.
Change suction line, if the friction losses in
the suction line are too high.
Check any strainers installed/suction opening.
Observe permissible speed of pressure fall.
✘ - - - - - - - Air intake at the shaft seal Supply external barrier fluid, if necessary, or
increase barrier fluid pressure.
Replace shaft seal.
✘ - - - - - - - Wrong direction of rotation Check the electrical connection of the motor
and the control system, if any.
✘ - - - - - - - Speed is too low.
- Operation with frequency inverter
- Operation without frequency inverter
- Increase voltage/frequency at the FI in the
permissible range.
- Check voltage.
✘ - - - - - ✘ - Wear of internal components Replace worn components by new ones.
- ✘ - - - - ✘ - Pump back pressure is lower than
specified in the purchase order.
Re-adjust to duty point.
In the case of persistent overloading, turn
down impeller.
6)
- ✘ - - - - - - Density or viscosity of fluid handled
higher than stated in purchase order
Contact the manufacturer.
- - - - - ✘ - - Use of unsuitable shaft seal materials
Change the material combination.
6)
A
B
C
D
E
F
G
H
5)
Pump pressure must be released before attempting to remedy faults on parts which are subjected to pressure.
6)
Contact the manufacturer.
8 Trouble-shooting
Normblock
47 of 58