A175-L 175-L32

Common issues

• Bearing wear (journal and thrust) due to contaminated oil, high loads, or insufficient lubrication, leading to increased vibration and potential rotor contact.
• Compressor fouling (dirt, oil mist, salt) reducing air flow and efficiency, leading to higher exhaust temperatures and reduced engine power.
• Turbine fouling (soot, unburnt fuel particles) on nozzle ring and turbine blades, causing reduced efficiency, increased exhaust back pressure, and potential rotor imbalance.
• Oil leakage from bearing casing seals (compressor side, turbine side) into charge air or exhaust gas, indicating seal wear or blocked drain lines.
• Rotor imbalance and excessive vibration, often a consequence of fouling, bearing wear, or foreign object damage (FOD) to blades.
• Erosion or corrosion of nozzle ring and turbine blades due to aggressive exhaust gas components or high temperatures.
• Cracks or deformation in the turbocharger casing (especially turbine side) due to thermal stress or excessive vibration.

Inspection checklist

• Monitor turbocharger RPM, bearing oil inlet/outlet temperatures and pressures, and charge air pressure/temperature against engine load and manufacturer's data.
• Inspect for abnormal noise (whining, grinding) or excessive vibration during operation. Use a vibration meter if available.
• Visually inspect compressor wheel for fouling, erosion, or foreign object damage (FOD) through inspection ports. Check for oil ingress.
• Visually inspect turbine wheel and nozzle ring for fouling, erosion, or damage through inspection ports. Check for exhaust gas leaks.
• Check for oil leaks around casing joints, bearing housing, and oil drain lines. Ensure drain lines are clear and flow freely.
• Inspect the condition of the air filter elements and charge air cooler for cleanliness and damage. Check differential pressure across air filter.
• Verify the integrity of flexible bellows and expansion joints on the exhaust gas and charge air sides for cracks or leaks.
• Check cooling water system (if applicable for bearing casing) for proper flow and temperature.
• Review engine room logbook for any reported alarms, performance deviations, or maintenance actions related to the turbocharger.

Service intervals

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Complete bearing cartridge (includes journal and thrust bearings, often supplied as an assembly).
• Set of O-rings, gaskets, and sealing rings for bearing casing and gas/air side seals.
• Oil pump (if externally driven or critical internal components for self-lubricating systems).
• Air filter elements (if applicable for combustion air intake).
• Compressor wheel nut and locking plate.
• Temperature sensors (bearing, exhaust gas) and speed sensor.
• High-pressure oil filter elements (if part of the turbocharger's dedicated lubrication system).

Safety

• High surface temperatures (exhaust gas casing can exceed 400°C) posing severe burn risk. Ensure insulation is intact.
• High rotational speeds (up to 15,000 RPM for large units) present a risk of rotor disintegration in case of catastrophic bearing failure, leading to potential casing rupture and projectile hazards.
• High pressure within the exhaust gas and charge air systems. Ensure all connections are secure before and during operation.
• Risk of fire from oil leaks onto hot surfaces. Maintain strict cleanliness and address any oil leaks immediately.
• Noise hazard during operation. Always wear appropriate hearing protection in the vicinity of operating turbochargers.

Class survey

Class surveyors typically verify the turbocharger's maintenance history and records (overhaul reports, spare parts used, running hours). They will conduct a visual inspection for external damage, oil/gas leaks, and proper securing of the unit. During engine trials, they observe for abnormal noise, vibration, and confirm operational parameters (RPM, temperatures, pressures) are within acceptable limits. The integrity of the air intake filter, exhaust gas system, and charge air cooler will be checked. Any evidence of poor maintenance or operational issues will be noted, potentially requiring further inspection or remedial action. Compliance with SOLAS regulations regarding hot surface insulation is also checked.

Estimated lifetime: 24,000 - 36,000 hours before major overhaul of the rotating assembly; total unit life can exceed 70,000 hours with regular maintenance and component replacement.