VarioTwin NG (104, 130)

Inspect mechanical seal gland for drip rate (should be steady drip, not continuous flow); check for visible leakage at casing joints. Monitor temperature of seal area. On maintenance-free seals (KL-RF), verify seal integrity without requiring regular oil filling.

Listen for cavitation sounds (like gravel passing through pump); record baseline suction and discharge pressures during commissioning and compare during operation. Verify NPSH margin is maintained, ensure suction strainer is clean and not blocked. Check that sludge tank heating coils maintain media at 60°C+ for high-viscosity media to prevent cavitation.

Listen for distinct rumbling or grinding noises indicating bearing wear. Monitor motor current draw against baseline (increased current = increased internal resistance). Observe vibration levels if vibration sensors are fitted. Perform visual inspection of rotor/stator assembly when accessible (X-LIFT quick-change systems allow Service in Place without full removal). Check free ball passages (up to 150 mm) are not obstructed.

Verify suction strainer is clear and accessible for cleaning. Monitor discharge pressure during operation (should match datasheet ratings: KB-S/KL-S up to 80 bar, Twin NG 30-80 bar). Check that suction connections (square/round flanges) are unobstructed. For vertical pumps (KL-T), verify water seal is present. Rotate standby pumps weekly to prevent seized bearings.

Inspect rotor and stator for wear patterns during periodic overhaul (annual in marine service). On X-LIFT quick-change systems (Xpress, BIO-MIX), verify cartridge design allows rapid replacement without pump removal. Check flexible joint condition (should show no oil weeping if joint is maintenance-free). Verify casting integrity for cast iron housings (KB-S GG). Document wear parts changed during maintenance for spare parts planning.