Service and Maintenance
CAUTION!
Before any work is started, check that the pump is isolated
from the power supply and cannot be energized.
Note:
In the appendix is a sectional drawing of a model of the B-series that is
representative for the majority of our sewage and industrial pumps.
Due to the large number of different models we have to ask you to contact your
Tsurumi dealer if you need a parts list or a drawing of a particular model.
Remove any debris attached to the pump´s outer surface, and wash the pump
with tap water. Pay particular attention to the impeller area, and completely
remove any debris from the impeller.
Verify that the paint is not peeled, that there is no damage, and that the bolts and
nuts have not loosened. If the paint has peeled, allow the pump to dry and apply
touch-up paint.
If the pump will not be operated for a long period of time, pull the pump up, allow
it to dry, and store it indoors.
If the pump remains immersed in water, operate the pump on a regular basis (i.e.
once a week) to prevent the impeller from seizing due to rust.
The pump must be overhauled even if the pump
appears normal during operation. The pump may
need to be overhauled earlier if it is used continuously
or repeatedly.
NOTE:
Contact your Tsurumi-dealer to overhaul
the pump.
Interval
1. Measuring insulation resistance
Monthly
Inspection Item
Insulation resistance reference value = 20M Ohm
NOTE:
The motor must be inspected if the
insulation resistance is considerably
lower than that obtained during the last
inspection
2. Measuring the loaded current
To be within the rated current
3. Measuring the power supply voltage
Power supply voltage tolerance=±5% of rated voltage
4. Inspecting the impeller
If the performance level has decreased considerably,
the impeller may be worn.
Once every 2 to 5 years
Overhaul
4
WARNING!
Never insert your hand or any other object into the inlet
opening on the underside of the pump casing when the pump
is connected to the power supply.
Before inspecting the pump casing, check that the pump has
been isolated from the power supply and cannot be energized.
Make sure that the pump is completely reassembled before putting into
operation again. Take care that bystanders keep a safe distance from the
conduit or switch gear and avoid contact with the water.
In one application, a pump can be under constant risk, and even with frequent attention may have a short live. In another application a pump can run for years without
any maintenance at all. Recommendations as to intervals, need interpretation, with the most hazardous characteristic in mind. At least superficial periodic inspection
is needed in order to maintain a certain level of reliability and safety.
Choking:
Access of the water to the pump and apparent discharge capacity obviously need to be checked as often as experience dictates. Basically, the inlet should be
protected from harmfully large solids, if they can be expected to be present, by a grating; e.g. the inlet to the pit can be screened off.
This is not applicable to aerators fitted with strainer except in open water with much vegetation or leaf fall. If in doubt, check that the impeller and volute are free of
solids and of thick deposits. First make sure that electric power cannot be accidentally applied.
Generating Set:
If power is provided by a generating set Hz to be within ±1 Hz, and voltage within ±5%, may need to be checked frequently. The lighter the generating set, the higher
the risk of erratic voltage and wrong frequency.
Insulation Check:
The following should not be done on automatic pumps such as e.g. U and PU because they have electronic parts. With them, a simple ohm meter has to be used
instead of an insulation tester which produces a test voltage. Less obvious than oil inspection but equally valuable, is a periodic check of insulation value between
the pump cable´s earth lead and the other leads, and between the other leads, by means of an insulation tester. This value, well over 20 M Ohm when the pump is
new or reconditioned, should be at least 1 M Ohm when the pump and its cable have been in the water for a long time. If it is down to 1M Ohm, repair in a workshop
is urgently needed. It is useful to keep a record of measurements of this insulation value, and of ampere draw if possible, over the years, so as to notice a steep
decline of the ohm value before a short occurs in the motor winding. Decreased ampere draw indicates impeller wear.
On workshop inspection, if it is found that the cable is at fault, it should not be re-used, even if 30 M Ohm insulation can be restored. If the motor is at fault, the
winding specialist can opt for ovendrying and revarnishing under vacuum, or in a favourable case drying only. In the latter case, dry at no more than 60°C with motor
protector still fitted or at not more than 105°C with motor protector removed. In case of oven drying, insulation should be higher than 5 M Ohm when hot or 20 M
Ohm when cooled down.
Oil:
Replace the oil also if it is slightly greyish or contains a droplet of water. Ensure that electric power cannot be accidentally applied to the pump. Lay the pump on its
side, remove the plug, holding a piece of cloth over it to prevent possible spraying. If the oil is greyish or contains water drops or dust, or if there is less than 80% of
the recommended quantity left, then measure carefully at the cable´s end (never open the motor outside a workshop) the ohm resistance between the leads and
replace shaft seal to avoid humidity getting into the motor and shorting the windings. Use turbine oil (ISO VG32). If the oil needs to be non-toxic (fish tank aeration,
food industry, etc) use high-quality paraffin oil of 28,8 to 35,2 cSt viscosity at 40°C.
Use the quantity specified in the specification table. Dispose of old oil in accordance with local regulations. Carefully check the packing (Gasket) of the filling plug
and replace.
Periodical inspection and
replacement of lubricant
(0,75 kW and less) : B, C, U, UZ, PU, TM, SFQ, SQ, FHP, FSP:
Inspection: Every 1500 hours of running time or every 6 months, whichever comes first
Changing interval: Every 3000 hours of running time or every 12 months , whichever comes first.
(1,5kW and more) : B, C, U, UZ, PU, SFQ, TRN, BER, MG, BZ:
Inspection: Every 6000 hours of running time or every 12 months, whichever comes first.
Changing Interval: Every 9000 hours of running time or every 24 months, whichever comes first
