Flowserve Centrifugal Pump 8-UB-1 Installation & Operation Instruction page 28

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