SN Series (40-660cc sizes)

Visual inspection of seal area for oil seepage; check seal faces for scoring, corrosion, or embedded particles. Perform pressure test at 1.5x rated pressure. Monitor seal cavity temperature with infrared thermometer (should not exceed +10°C above ambient).

Measure spindle surface hardness using hardness tester (Allweiler specification typically 58-62 HRC); inspect under magnification for scoring marks or polishing wear patterns. Check for abnormal noise during operation indicating rotor contact. Take oil samples for ferrous particle analysis (target <25mg/l).

Check bearing temperature (should not exceed 90°C or +15°C above inlet oil); verify bearing oil level monthly; perform oil change every 8,000 operating hours or 12 months. Test oil viscosity at operating temperature (ISO 6743 analysis). Monitor for bearing cage wear or noise during run-in.

Test relief valve opening pressure at no-load condition (should match nameplate +/-0.5 bar). Verify valve closes cleanly without chattering. Check for external bypass leakage using flow meter at relief setting. Inspect valve seat and poppet under magnification for deposits or erosion.

Perform ISO 4406 particle count analysis monthly (target <16/14/11 or better); test water content via Karl Fischer coulometric titration (target <500ppm); monitor viscosity drift (±10% of nominal at 40°C). Inspect immersion tubes/suction strainers for sediment blockage. Check breather condition weekly.