A100-H 100-H42

Common issues

• Bearing wear (journal and thrust bearings) leading to increased axial/radial play and potential rotor contact.
• Compressor fouling due to dirty intake air, oil carry-over from engine breather, or poor air filter maintenance, reducing efficiency and airflow.
• Turbine fouling from incomplete combustion, poor fuel quality, or exhaust gas boiler issues, leading to reduced power and higher exhaust temperatures.
• Nozzle ring and turbine blade damage (e.g., erosion, foreign object damage (FOD), thermal cracking), impacting efficiency and potentially leading to imbalance.
• Oil leakage from bearing housings or oil supply/drain lines, indicating seal wear or bearing issues, posing fire risk and oil consumption.
• Rotor imbalance and vibration, often caused by fouling, blade damage, or bearing wear, leading to accelerated component fatigue.
• Surging, which can be caused by engine issues (e.g., fuel pump, injector problems), turbocharger mismatch, or severe fouling, leading to cyclic stress.
• Cracks in the turbine or compressor casings due to thermal stress, vibration, or improper tightening.

Inspection checklist

• Visual inspection of compressor and turbine wheels for fouling, erosion, cracks, or foreign object damage (FOD).
• Check rotor axial and radial play using a dial gauge to assess bearing condition. Compare readings to manufacturer's limits.
• Inspect for oil leakage around bearing housings, oil supply/drain connections, and casing joints.
• Examine the integrity of the turbocharger casing, insulation, and mounting bolts for cracks, corrosion, or looseness.
• Verify the condition of the engine's air intake filter system, ensuring it is clean and properly sealed.
• Check exhaust gas inlet and outlet ducts for deposits, leaks, and proper expansion joint function.
• Monitor lubricating oil pressure and temperature at the turbocharger inlet, ensuring it's within specified parameters.
• Assess vibration levels (audibly and via monitoring systems if available) for any unusual patterns or increases.
• Confirm proper function of the turbocharger speed sensor and associated monitoring system.
• Inspect the condition of the water washing system (if fitted) and ensure drainage points are clear.

Service intervals

Typical intervals for this design class, not the manufacturer’s figures for your model. The manufacturer’s manual is binding.

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 / Bearing set (journal and thrust bearings)
• Gasket and O-ring set for overhaul
• Oil sealing rings / Labyrinth seals
• Impeller nut (left-hand thread)
• Speed sensor
• Lubricating oil filter elements (if applicable to T/C oil system)
• Nozzle ring (if operating conditions are harsh or damage is common)

Safety

• High surface temperatures (exhaust casing, oil lines) posing severe burn risk. Ensure lagging is intact.
• Extremely high rotational speeds (up to 100,000+ RPM) of the rotor, necessitating strict adherence to maintenance procedures to prevent catastrophic failure.
• Pressurized components (compressor outlet, exhaust inlet) requiring proper depressurization before opening.
• Hot lubricating oil and potential oil mist leakage, which can create a fire hazard in the engine room.
• High noise levels during operation, requiring hearing protection in the vicinity.

Class survey

Class surveyors typically focus on verifying the turbocharger's operational integrity and safety. This includes reviewing maintenance records (last overhaul, bearing renewals, running hours), logbook entries for performance parameters (boost pressure, exhaust temperatures, oil pressure/temperature, RPM), and confirming the functionality of safety devices (e.g., overspeed trip, alarms). They will visually inspect for external leaks, casing integrity, proper securing, and intact insulation. Verification of spare parts inventory for critical items and accessibility for inspection/maintenance are also key points. Any signs of excessive vibration, unusual noise, or significant performance degradation will trigger further investigation.

Estimated lifetime: 16,000 - 24,000 running hours (before major overhaul, assuming proper maintenance)