Wilo Wilo-Drain SP, Инструкция по установке и эксплуатации

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ENGLISH
20
10 FAULTS, CAUSES AND REMEDIES
Fault Cause Remedy
Pump does not
prime
- Pump had to be stopped before it was primed Check theoretical priming time
Check that grease cartridge was activated
Check that temperature sensor trip is set properly (ATEX versions)
- No liquid in priming chamber or liquid level is too low Fill pump casing with fluid
Check level switches position
- Air intake in suction line Check shape of connections and threads
Check tightening of hoses fastening collars
Proceed with replacement of damaged hoses
Do sealing operations again if necessary
- Impeller or casing wear plate is worn Replace wear plate or impeller
Check pump working conditions
- Liquid temperature in pump is to high Fill the pump with cold liquid
- Pressurized discharge pipe Add a vent valve between the check valve and the discharge flange or
add a dedicated discharge pipe back to the pit
- Motor speed is too low Check tightening of power supply cable connections
Check motor current consumption
Increase frequency up to 50Hz (if a frequency inverter has been supplied)
- Air intake through the shaft sealing. Leaking mechanical seal. Replace grease cartridge
Replace mechanical seal
In case of emergency : grease copiously mechanical seal faces and back
of the stationary seat with high viscosity grease
- Wrong motor direction of rotation Change two phases in motor junction box
The pump is not
producing the rated
flow or head
- Discharge pressure is too high Open and clean discharge pipe
Check pump duty point
- Pump or piping is not completely vented Vent pump casing and suction line
- Suction lift is too high / NPSH available is too low Check fluid level in the tank and check max flow according to pump curve
Check isolating valve is opened on the pump suction side
Clean the strainer if any
- Clearance between the impeller and the wear plate(s) is
excessive Check wear plate(s) thickness
Replace worn wear plate(s) by new one(s)
- Wrong direction of rotation Change two phases in motor junction box
- Leakage on pump casing gaskets, on shaft sealing or on suction
piping Replace casing seal(s)
Check shaft sealing
Check the state of the flanges seals
Pump is not lifting
liquid
- Air leaks into pump through mechanical seal, sleeve, clogged
strainer or leakage in suction line Replace casing seal(s)
Check shaft sealing
Check the state of the flanges seals
- Suction lift is too high or head losses in suction line are excessive Check fluid level
Check that the available NPSH of the process is higher than the required
NPSH of the pump
- Too much foreign matter in pump casing or part blocked inside
the impeller Open visit port and clean the inside of the pump
The pump leaks
- Casing seal(s) leaking Tighten bolts and screws according the provided tightening torque values
Check the state of the gaskets
- Mechanical seal is leaking Check the state of the mechanical seal faces and O’Ring
Proceed with replacement of the mechanical seal
Replace grease cartridge by a new one
The pump runs
noisily
- Ball bearing in bearing bracket or in motor is worn or destroyed Replace ball bearings
- Incorrect inflow of circulation liquid Cavitations : check pump duty point
- Suction head is too high or discharge head to low Check fluid level in the tank and open all valves set on suction pipe
Check pump discharge pressure
Clean the strainer
- Wrong assembly of the base plate on its foundations or
unauthorized forces applied to pump flanges Check pump installation
Check lining of coupling
- Foreign matter remains inside the pump casing Open visit port and clean the pump
Motor protection
switches off
- Current leakage Check earthing of the motor
Check for current leakage : damaged cables, fluid leakage on electrical
components …
- Protection fuses not calibrated properly Check motor absorbed power and select motor protections accordingly.
- Liquid density higher than expected Calculate absorbed power and replace motor accordingly
- Pump runs right of curve or out of application limits Measure pump duty point and check pump runs in authorized application
limits. If necessary add a regulating valve or a calibrated orifice on pump
discharge line
- Foreign matter remains inside the pump casing Open visit port and clean the pump