A180-L 180-L32

Common issues

• Bearing wear (journal and thrust bearings) due to contaminated oil, insufficient oil supply, or excessive vibration, leading to increased clearances and potential rotor contact.
• Turbine fouling/erosion from poor fuel quality (high sulfur, catalytic fines) or improper water washing, resulting in reduced efficiency, increased exhaust back pressure, and potential rotor imbalance.
• Compressor fouling from dirty intake air, leading to reduced air flow, decreased boost pressure, surging, and reduced engine power.
• Nozzle ring deformation or cracking due to thermal stress, foreign object damage, or prolonged exposure to high temperatures, affecting turbine efficiency and gas flow.
• Rotor imbalance causing excessive vibration, often a secondary effect of fouling, erosion, or physical damage to the compressor or turbine wheels.
• Oil leakage from bearing housings or sealing air system, indicating worn seals, incorrect oil pressure, or issues with the sealing air supply.
• Surging, often caused by compressor fouling, incorrect engine tuning, exhaust gas system issues, or sudden load changes, leading to high stress on components.

Inspection checklist

• Check for oil and exhaust gas leaks around casings, flanges, and drain lines. Pay attention to the compressor and turbine side bearing housings.
• Measure axial and radial bearing clearances (if accessible or during scheduled overhaul) to assess bearing wear against manufacturer's limits.
• Inspect compressor wheel for fouling, erosion, foreign object damage (FOD), and verify tip clearance. Check air filter elements condition.
• Inspect turbine wheel and blades for fouling, erosion, cracks, and FOD. Verify tip clearance and check for signs of rubbing.
• Examine nozzle ring for fouling, cracks, deformation, and foreign object damage. Ensure free movement of variable geometry vanes if fitted.
• Verify condition of lubricating oil system: check oil pressure, temperature, and differential pressure across oil filters. Take oil samples for analysis.
• Assess vibration levels using portable equipment or by monitoring permanently installed sensors. Listen for abnormal noises (e.g., rubbing, whistling).
• Inspect mounting bolts, chocks, and anti-vibration elements for integrity, tightness, and signs of corrosion or fatigue.
• Check the functionality and condition of the water washing system (if fitted) for both compressor and turbine sides, including spray nozzles and drainage.
• Review turbocharger performance parameters (RPM, boost pressure, exhaust gas temperatures before/after turbine, bearing temperatures) against baseline and normal operating ranges.

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 assembly (including journal and thrust bearings, seals, and associated O-rings/gaskets)
• Full gasket and O-ring sets for casing, oil, and gas connections (essential for any opening/closing operation)
• Sealing air labyrinth rings/seals (for both compressor and turbine sides)
• Lubricating oil filter elements (high-quality filters are crucial for bearing longevity)
• Nozzle ring segments (or a complete nozzle ring, depending on design and common failure modes)
• Special tools for disassembly and assembly (e.g., lifting gear, torque wrenches, bearing extraction tools)
• Air filter elements (if applicable for the turbocharger's intake system)

Safety

• High Temperatures: Exhaust gas and casing surfaces can reach 400-550°C. Risk of severe burns. Always use appropriate PPE and allow for cooling before work.
• High Rotational Speed: The rotor operates at tens of thousands of RPM. Catastrophic failure can release high-energy fragments. Ensure overspeed trip is functional and never exceed rated RPM.
• High Pressure: Compressor discharge air is under significant pressure (up to 5 bar gauge or more). Depressurize systems before opening.
• Hot Oil Under Pressure: Lubricating oil system operates at elevated temperatures and pressures. Risk of oil spray and burns during maintenance.
• Noise Hazard: Operating turbochargers produce high noise levels (often >100 dB). Hearing protection is mandatory in the vicinity.

Class survey

Class surveyors typically focus on the overall operational integrity and safety of the turbocharger. They will check for: general condition and cleanliness, absence of oil/exhaust gas leakage, abnormal noise or vibration during operation, and review of performance parameters (RPM, boost pressure, temperatures) from logbooks. Verification of the last overhaul date and scope of work, along with supporting documentation (service reports, spare parts used). Functionality of safety devices, particularly the overspeed trip, is often verified or records reviewed. If the turbocharger is opened for maintenance during the survey, bearing clearance measurements will typically be witnessed. Integrity of mounting arrangements and exhaust gas insulation will also be checked.

Estimated lifetime: With diligent maintenance, adherence to service intervals, and timely replacement of wear parts, the main casing and rotor shaft can last 100,000 to 150,000+ running hours. Major overhauls typically occur every 36,000-48,000 hours, involving significant refurbishment and component replacement.