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Troubleshooting

9 New impeller
Corrosion problems
9 Upgrade the material selection
9 Check change in pumpage
Erosion problems

9 Upgrade the material selection
9 Check change in pumpage
Cavitation damage
9 See Figure 11.2

Suction Recirculation
9 See Figure 11.2
9 Check the specific speed of impeller
Discharge Recirculation
9 See Figure 11.2

9 Check for vane passing frequency
Air entrainment
9 See Figure 11.2
9 Check configuration of inlet piping

9 Check arrangement of suction source
Temperature problems
9 Check impeller axial clearance
9 Check wear ring clearance
9 Check for change in pumpage
Impeller seizing

9 Check impeller axial clearance
9 Check wear ring clearance

11.5.2 Wear rings

Corrosion problems
9 Upgrade the material selection
9 Check change in pumpage

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