Alfa Laval LKH Evap

Common issues

• Mechanical seal leakage or failure from dry running or suction-side cavitation
• Cavitation from low available NPSH in evaporator vacuum service, often from undersized or fouled suction piping
• Impeller wear from scale or entrained solids in the evaporator feed
• Bearing wear from misalignment on the close-coupled motor/pump arrangement
• O-ring/gasket degradation from temperature cycling in evaporator service

Inspection checklist

• Check the mechanical seal for leakage during operation
• Check for cavitation noise or vibration, especially at low evaporator vacuum
• Inspect the impeller for scale build-up or erosion when opened for seal service
• Check motor/pump alignment at the bearing housing on close-coupled units
• Verify the suction strainer, if fitted, is clean
• Check flow/discharge pressure against the pump curve baseline

Service intervals

Critical spares

• Mechanical seal (complete unit)
• O-ring/gasket kit for the pump casing
• Impeller
• Shaft key/circlip set used in the seal/impeller assembly

Safety

• Evaporator distillate/feed can be at elevated temperature - hot surface and scald risk when opening the pump
• Confirm the evaporator is vented/isolated before pump maintenance on a vacuum system
• Rotating shaft hazard if the coupling guard is removed

Class survey

Where this pump serves the fresh water generator/evaporator, class and flag expect documented product water quality monitoring rather than a pump-specific survey item; the pump itself is typically covered under general auxiliary machinery maintenance records.