salmson NEX Manuel D'installation Et Mise En Service page 52

‐ Shaft bent
seal leaks
excessively
‐ Bearings worn
‐ Leakage under sleeve due to seal failure
‐ Shaft sleeve worn or scored or running off center
‐ Mechanical seal improperly installed
‐ Incorrect type of mechanical seal for operating conditions
‐ Shaft running off center because of worn bearings or misalignment
‐ Impeller out of balance resulting in vibration
‐ Abrasive solids in liquid pumped
‐ Internal misalignment of parts preventing seal ring and seat from mating
properly
‐ Mechanical seal was run dry
‐ Internal misalignment due to improper repairs causing impeller to rub
‐ Speed too high
‐ Total head of system lower than pump design head
‐ Specific gravity of liquid different from design
‐ Viscosity of liquid differs from that for which designed
‐ Operating at high capacity
‐ Misalignment due to pipe strain
Pump
requires
‐ Shaft bent
excessive
power ‐ Rotating part rubbing on stationary part internally
‐ Wearing ring surfaces worn
‐ Mechanical seal improperly installed
‐ Incorrect type of mechanical seal for operating conditions
‐ Abrasive solids in liquid pumped
‐ Wrong direction of rotation
‐ Motor running on two phases only
‐ Pump or suction pipe not completely filled with liquid
‐ Suction lift too high or level too low
Pump loses
‐ Excessive amount of air or gas in liquid
‐ Air or vapor pocket in suction line
prime after
‐ Air leaks into suction line
starting
‐ Air leaks into pump through mechanical seal, sleeve gasket, casing seal or pipe
lugs
‐ Inlet of suction pipe insufficiently submerged
‐ Excessive amount of air or gas in liquid
‐ Speed too low
‐ Total head of system higher than differential head of pump
Insufficient
pressure
‐ Viscosity of liquid differs from that for which designed
developed
‐ Wearing ring surfaces worn
‐ Impeller damaged or eroded
‐ Wrong direction of rotation
‐ Pump or suction pipe not completely filled with liquid
‐ Suction lift too high or level too low
‐ Insufficient margin between suction pressure and vapor pressure
‐ Excessive amount of air or gas in liquid
‐ Air or vapor pocket in suction line
‐ Air leaks into suction line
‐ Air leaks into pump through mechanical seal, sleeve gasket, casing seal or pipe
lugs
Insufficient
‐ Foot valve too small
capacity
‐ Foot valve partially clogged
delivered
‐ Inlet of suction pipe insufficiently submerged
‐ Speed too low
‐ Total head of system higher than differential head of pump
‐ Viscosity of liquid differs from that for which designed
‐ Wearing ring surfaces worn
‐ Impeller damaged or eroded
‐ Wrong direction of rotation
‐ Motor running on two phases only
‐ Motor running too slow
‐ Pump not primed or filled with liquid
‐ Pump or suction pipe not completely filled with liquid
‐ Suction lift too high or level too low
Pump does
‐ Insufficient margin between suction pressure and vapor pressure
not deliver
‐ Air or vapor pocket in suction line
liquid
‐ Inlet of suction pipe insufficiently submerged
‐ Speed too low
‐ Total head of system higher than differential head of pump
Check shaft runouts are within acceptable values
Consult Salmson
Replace bearings
Replace seal and check for damage
Check and renew defective parts
Check alignment of faces or damages parts and assembly method used
Consult Salmson
Check misalignment and correct it if necessary. If alignment satisfactory
check bearing for excessive wear
Check and consult Salmson
Check and consult Salmson
Check and consult Salmson
Check mechanical seal condition and source o f dry running and repair
Check method of assembly, possible damage or state of cleanliness
during assembly.
Remedy or consult Salmson if necessary
Consult Salmson
Check system losses and consult Salmson
Check and consult Salmson
Check and consult Salmson
Measure the value and check maximum permitted.
Remedy or call Salmson
Check the flange connections and eliminate strains using elastic
couplings or a method permitted
Check shaft run outs are within acceptable values
Consult Salmson
Check and consult Salmson if necessary
Replace worn wear ring/surfaces
Check alignment of faces or damages parts and assembly method used
Consult Salmson
Check and consult Salmson
Reverse two phases at motor terminal box
Check power supply and fuses
Vent and /or prime
> NPSH
Check NPSH , proper submergence, losses at strainers and
A R
fittings
Check and purge pipes and system
Check suction line design for vapor pockets
Check suction line is air tight
Check and replace faulty parts
Remedy or consult Salmson
Check out system design
Check and purge pipes and system
Consult Salmson
Check system losses
Remedy or consult Salmson
Check and consult Salmson
Replace worn wear ring/surfaces
Replace or consult Salmson for improved material selection
Reverse two phases at motor terminal box
Vent and /or prime
> NPSH
Check NPSH , proper submergence, losses at strainers and
A R
fittings
> NPSH
Check NPSH , proper submergence, losses at strainers and
A R
fittings
Check and purge pipes and system
Check suction line design for vapor pockets
Check suction line is air tight
Check and replace faulty parts
Remedy or consult Salmson
Investigate replacing the foot valve
Clean the foot valve
Check out system design
Consult Salmson
Check system losses
Remedy or consult Salmson
Check and consult Salmson
Replace worn wear ring/surfaces
Replace or consult Salmson for improved material selection
Reverse two phases at motor terminal box
Check power supply and fuses
Check motor terminal box connections and voltage
Check for complete filling
Vent and /or prime
> NPSH
Check NPSH , proper submergence, losses at strainers and
A R
fittings
> NPSH
Check NPSH , proper submergence, losses at strainers and
A R
fittings
Check suction line design for vapor pockets
Check out system design
Consult Salmson
Check system losses
Remedy or consult Salmson
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ENGLISH