UB USER INSTRUCTIONS ENGLISH 71569247 07-04
Page 28 of 32
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FAULT SYMPTOM
P u m p o v e r h e a t s a n d s e i z e s
⇓⇓⇓⇓
⇓⇓⇓⇓
B e a r i n g s h a v e s h o r t l i f e
⇓⇓⇓⇓
⇓⇓⇓⇓
P u m p v i b r a t e s o r i s n o i s y
⇓⇓⇓⇓
⇓⇓⇓⇓
M e c h a n i c a l s e a l h a s s h o r t l i f e
⇓⇓⇓⇓
⇓⇓⇓⇓
M e c h a n i c a l s e a l l e a k s e x c e s s i v e l y
⇓⇓⇓⇓
⇓⇓⇓⇓
P u m p r e q u i r e s e x c e s s i v e p o w e r
⇓⇓⇓⇓
⇓⇓⇓⇓
P u m p l o s e s p r i m e a f t e r s t a r t i n g
⇓⇓⇓⇓
⇓⇓⇓⇓
I n s u f f i c i e n t p r e s s u r e d e v e l o p e d
⇓⇓⇓⇓
⇓⇓⇓⇓
I n s u f f i c i e n t c a p a c i t y d e l i v e r e d
⇓⇓⇓⇓
⇓⇓⇓⇓
P u m p d o e s n o t d e l i v e r l i q u i d
⇓⇓⇓⇓
⇓⇓⇓⇓
PROBABLE CAUSES
POSSIBLE REMEDIES
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Impeller damaged or eroded.
Replace impeller and check reason.
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Leakage under sleeve due to joint failure.
Replace joint and check for damage.
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Mechanical seal improperly installed.
Check alignment of faces or damaged parts and
assembly method used.
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Incorrect type of mechanical seal for operating
conditions.
Consult Flowserve
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Shaft running off centre because of worn
bearings or misalignment.
Check misalignment and correct if necessary.
If alignment satisfactory check bearings for
excessive wear.
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Impeller out of balance resulting in vibration.
Check and consult Flowserve.
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Abrasive solids in liquid pumped.
Check and consult Flowserve.
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Mechanical seal was run dry.
Check mechanical seal condition and source of
dry running and repair.
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Internal misalignment due to improper repairs
causing impeller to rub.
Check method of assembly, possible damage or
state of cleanliness during assembly.
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Excessive thrust caused by a mechanical failure
inside the pump.
Check wear condition of impeller, its clearances
and liquid passages.
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Excessive grease in ball bearings.
Check method of regreasing.
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Lack of lubrication for bearings.
Check hours run since last change of lubricant,
the schedule and its basis.
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z
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Improper installation of bearings.
Check method of assembly, possible damage or
state of cleanliness during assembly and type of
bearing used.
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z
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Damaged bearings due to contamination.
Check contamination source and replace
damaged bearings.
C. ELECTRICAL TROUBLES
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Wrong direction of rotation.
Reverse 2 phases on motor terminal box.
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Motor running too slow.
Check motor terminal box connections.
