Goulds Pumps ICB - IOM - Manual (Page 26)

Installation, Operation and Maintenance Instruction Model ICB
ICB 100-English page 17 Revision 00
Article No 21999991 Issue 05/2006
Store stand-by pumps according to point 6.8.
10. Faults - Causes and Solutions
The following notes on causes of faults and how to
repair them are intended as an aid to recognising the
problem. The manufacturer's Customer Service
Department is available to help repair faults that the
operator cannot or does not want to repair. If the operator repairs or changes the pump, the design
data on the data sheet and chapter 2 of these
Operating Instructions should be particularly taken
into account. If necessary, the written agreement of
the manufacturer must be obtained.
Discharge too low Discharge stops after a time Head too low Head too high Drive mechanism overloaded Pump not running quietly Temperature in pump too high Temperature in shaft sealing too high Temperature at the bearing too high Pump leaking Leakage rate at shaft sealing too high
Cause Solution
■ Back-pressure too high • check facility for pollution, open discharge valve
• reduce resistance in discharge pipe (e.g. clean filter if
necessary)
• use larger impeller (note available motor power)
■ ■ ■ Back-pressure too low, discharge too low
• throttle discharge valve
■ ■ Speed too high • reduce speed
• compare speed of motor with specified pump speed (rating
plate)
• when adjusting speed (frequency transformer) check
reference value setting
■ ■ Speed too low • increase speed (check available motor power)
• compare speed of motor with specified pump speed (rating
plate)
• when adjusting speed (frequency transformer) check
reference value settings
■ ■ ■ ■ Flow too little • increase min. flow (open discharge valve, bypass)
■ Flow too big • reduce flow (throttle discharge valve)
■ ■ Impeller diameter too big • use smaller impeller
■ ■ Impeller diameter too small • use larger impeller (check available motor power)
■ ■ ■ ■ Pump and/or pipes not completely filled with liquid • fill
• vent
■ ■ ■ Pump or suction/intake pipe blocked • clean
■ ■ Air pocket in pipeline • vent
• improve course of pipe
■ ■ ■ ■ ■ Suction height too big / NPSH of system too small
• increase liquid level and admission pressure
• reduce resistance in the intake/suction pipe (change course
and rated width, open shut-off valves, clean filters)
■ ■ ■ Air being sucked in • increase liquid level
• check if suction pipe is vacuum-tight
■ ■ ■ Air being sucked in through shaft sealing • clean sealing pipe
• increase sealing pressure
• replace shaft sealing
■ ■ Direction of rotation is wrong • swap over two phases of power supply (to be done by an
electrician)
■ ■ ■ ■ Inner components suffering from wear • replace worn parts
■ ■ ■ Density and/or viscosity of liquid handled is too high • seek assistance
■ ■ Lines and roughness at shaft • replace parts
■ ■ Deposits on mechanical seal
• clean
• replace mechanical seal if necessary
• if necessary provide additional rinsing or quench
■ ■ Impeller out of balance
• remove blocks/deposits
• replace impeller if broken or unevenly worn
• check shafts to ensure that they are running true
■ ■ ■ ■ ■ Forces in pipeline too high (pump unit under strain) • change (support pipes, use compensators, etc.)
• is foundation plate/frame properly cast in place?
■ Electricity supply not right (2-phase running) • check voltage of all phases
• check cable connections and fuses
■ Sealing insufficient • tighten screws
• replace sealing
■ ■ Bearing damaged • replace