Sulzer VMS - Failures; Failure Table

26 Installation, Operating and Maintenance Instructions (Original Instructions)
VMS Vertical Multistage Pumps
26
10 Failures
10.1 Failure table
Observe the general safety precautions before installation, maintenance and repair.
Problem Possible cause Possible solution Checkpoints
Leakage along the shaft. Running surfaces of the
mechanical seal are worn or
damaged.
Replace the mechanical
seal.
Check the pump for dirt /
abrasive parts.
New pump: seal stuck due
to assembly.
Open and close the outlet
shut-o󰀨 valve quickly during
operation.
Mechanical seal mounted
incorrectly.
Install the mechanical seal
correctly. Use water and
soap as a lubricant.
Elastomers a󰀨ected by
medium.
Use the right rubber compound
for the mechanical
seal.
Pressure too high. Use the right type of mechanical
seal.
Shaft worn. Replace shaft and mechanical
seal.
Pump has been operating
without water.
Replace the mechanical
seal.
Leakage along the shroud at
the top bracket or at the pump
casing.
O-ring worn Replace the o-ring.
O-ring not resistant to the
medium to be pumped.
Replace o-ring by one with
better resistance.
Too much stress on the pump
casing; it becomes oval.
Decrease stress on piping.
Mount the pump casing
without stress.
Support the connections.
Pump is vibrating or noisy. Coupling mounted incorrectly. Install the coupling in parallel.
Faulty setting of the hydraulic
assembly.
Adjust the assembly according
to the manual.
There is no water in the pump. Fill and vent the pump.
No supply of medium. Make sure there is su󰀩cient
supply. Check for blockages in
the supply line.
Bearings of pump and/or motor
worn.
Have the bearings replaced by a
certied company.
Available NPSH too low
(cavitation).
Improve suction condition.
Pump does not work in its
working range.
Select another pump or adjust
the system to work within its
working range.
Pump is standing on an uneven
surface.
Level the surface.