Inspection; Dismantling The Pump - Grundfos SE1 50 Installation And Operating Instructions Manual

10.1 Inspection

Pumps running normal operation should be inspected every
3000 operating hours or at least once a year. If the pumped liquid
is very muddy or sandy, inspect the pump at shorter intervals.
Pumps with sensor offer the possibility of constant monitoring
key components in the pump, such as shaft seal condition,
bearing temperature, winding temperature, insulation resistance
and moisture in the motor.
Check the following points:
• Power consumption
See pump nameplate.
• Oil level and oil condition
When the pump is new or after replacement of the shaft seal,
check the oil level and water content after one week of
operation.
If there is more than 20 % extra liquid (water) in the oil
chamber, the shaft seal is defective. The oil should be
changed after 3000 operating hours or once a year.
Use Shell Ondina 919 oil or similar type.
See section 10.2.1 Oil change.
• Cable entry
Make sure that the cable entry is watertight (visual inspection)
and that the cable is not sharply bent and/or pinched.
• Pump parts
Check impeller, pump housing, etc. for possible wear.
Replace defective parts.
See section 10.2.2 Removing the pump housing and
• Ball bearings
Check the shaft for noisy or heavy operation (turn the shaft by
hand). Replace defective ball bearings.
A general overhaul of the pump is usually required in case of
defective ball bearings or poor motor function. This work must
be carried out by Grundfos or a service workshop authorized
by Grundfos.
Warning
Defective bearings may reduce the Ex safety.
• O-rings and similar parts
During service/replacement, it must be ensured that the
grooves for the O-rings as well as the seal faces have been
cleaned before the new parts are fitted.
Note Used rubber parts must not be reused.
Warning
Explosion-proof pumps must be checked by an
authorized Ex workshop once a year.
24

10.2 Dismantling the pump

10.2.1 Oil change
After 3000 operating hours or once a year, change the oil in the
oil chamber as described below.
If the shaft seal has been replaced, the oil must be changed.
Warning
When loosening the screws of the oil chamber, note
that pressure may have built up in the chamber. Do
not remove the screws until the pressure has been
fully relieved.
Draining of oil
1. Place the pump on a plane surface with one oil screw pointing
downwards.
2. Place a suitable container (approx. 1 litre), for instance made
of transparent plastic material, under the oil screw.
Used oil must be disposed of in accordance with
Note
local regulations.
3. Remove the lower oil screw.
4. Remove the upper oil screw.
If the pump has been in operation for a long period of time, if
the oil is drained off shortly after the pump has been stopped,
and if the oil is greyish white like milk, it contains water. If the
oil contains more than 20 % water, it is an indication that the
shaft seal is defective and must be replaced. If the shaft seal
impeller.
is not replaced, the motor will be damaged.
If the quantity of oil is smaller than the quantity stated in
section 10.4 Oil
5. Clean the faces for the gaskets for oil screws.
Filling with oil
1. Turn the pump so that the oil filling holes are placed opposite
to each other, pointing upwards.
Fig. 18 Oil filling holes
2. Pour oil into the chamber.
For oil quantity, see section
3. Fit the oil screws with new gaskets.
quantities, the shaft seal is defective.
Oil filling/venting
10.4 Oil quantities.