LEM / LEMR / LEMA / LEMB

Monitor seal flush flow rate and discharge temperature daily on critical pumps. Inspect visible signs of leakage around seal area. Replace seals at manufacturer-recommended intervals (typically 2,000-5,000 operating hours depending on application). Verify mechanical seal material compatibility with pumped liquid.

Measure coupling alignment using dial indicators or laser alignment tools to maintain within 0.1 mil/inch angular tolerance and 0.002 inch per inch axial tolerance. Check for parallel, angular, and axial misalignment. Verify alignment after any mechanical work or maintenance. Re-check monthly during operation.

Inspect bearing oil for water content and discoloration. Feel all bearing housings for excessive temperature (baseline + 10°C or more indicates problems). Check oil rings and filling ports. Verify lubrication grade matches OEM specification. Establish baseline vibration readings (horizontal, vertical, axial) at bearing locations; any increase >25% signals developing bearing issues.

Verify positive suction head is sufficient (minimum recommended 0.5-1.5 m depending on pump model). Check suction strainers for blockage and clean as required. Monitor discharge pressure for fluctuations. Listen for cavitation noise (grinding/rattling sound). Inspect impeller for erosion/pitting during disassembly. Verify suction piping diameter and validate with NPSH calculations.

Establish baseline vibration signature when pump is new or after overhaul. Measure at bearing housings in three axes (horizontal, vertical, axial). Monitor periodically using vibration analysis equipment. Alert threshold: any reading increase of 25% above baseline. Investigate root causes: imbalance, misalignment, bearing wear, cavitation, or loose mounting bolts. Recalibrate after repairs.