Maintenance; Routine Maintenance And Frequency Of Inspection - Wilo MISO 25-125 Manual

9 Maintenance

Maintenance and repair work should be carried out by
qualified personnel only.
WARNING! Danger of electric shock!
Any danger from electrical current should be ruled
out.
• The pump should be electrically isolated and secured
against unauthorized switch-on prior to any
maintenance or repair work.
• Any damage to the connection cable should always be
rectified by a qualified electrician only.
WARNING! Risk of scalding!
At high fluid temperatures and system pressures,
allow the pump to cool down first and then
depressurise the system.
9.1 Routine maintenance and frequency of
inspection
Centrifugal pump requires
maintenance; however, serious troubles can be often
avoided by regular observation and analysis of various
working parameters. Some of the routine maintenance
checks for this purpose are as under:
Routine maintenance
Parts
Mechanical Seal Check for Leakage
Gland Packing Check for Leakage
Check for Leakage
Bearings Check temperature
Suction Pressure Check Pressure
Discharge Pressure Check Pressure
Flushing Check Flow
Vibration Vibration
Voltage and Current Check for the rated values
Rotating element Check the rotating for wear
Clearances Check the clearances between
neck ring and impeller
Total Dynamic Head Check Suction and Discharge
TDH
Alignment Check the alignment of pump
with motor
NOTE:
The above Routine Maintenance checklist is for pump only. Refer Motor / Engine manufacturers manual for the respective routine
maintenance checks.
Tightening torques – Untreated Screw (black finish); Coefficient of Friction 0.14
Property
Torque
Class
M6
8.8 Nm 9
Ft.lb 7
Installation and operating instructions WILO Mather and Platt –MISO / PISO Pumps
very little routine
Action
Nominal Diameter - Course Thread
M8 M10 M12 M14
22 44 76 122
16 33 56 90
• To keep daily logbook records of working parameters like
suction and discharge pressure, flow rate, current drawn,
bearing temperature, etc. These parameters should be
recorded twice a shift. Any sudden change should be a
signal for investigation. Refer Section Maintenance &
Inspection log.
• Check bearings for normal temperature. See 8.3.3 Pg. No.
20
• Vibration & sound level readings should be taken once in
a fortnight and values compared with that of previous
records.
• Check that there is sufficient leakage from the gland
packing to ensure proper cooling and lubrication. (if
applicable) For mechanical seal, check that there is no
visible leakage.
• For any abnormality observed from the visual/ manual
inspection and through maintenance & inspection logs,
stop the pump and investigate.
• Fault finding - Many of the common faults which occur on
centrifugal pumps and which can be diagnosed by
observations are given in the chart under section 10
Faults, causes and remedies.
Period Remarks
Daily
5.6 gm/hr. per pair of seal face
Daily 40-60 drops/minute
Half yearly If required replace with new packings
Weekly If Bearing temperature exceeds 80
needs to be rectified.
Daily
Daily
Weekly Flow through the Flushing pipes must be clear
and continuous
Weekly Refer acceptable field vibration limit chart
Pg. No. 27
Weekly
Yearly
Yearly If value of clearance is more, neck ring should
be replaced, Ref. Technical Data Pg. No. 12
Yearly
Half yearly Refer table for alignment tolerances, Pg. No. 16
M16 M20
190 300
140 221
0
C, the fault
21