IHI BBC VTR 161-2 Turbocharger

IHI BBC VTR 161-2 Turbocharger | Marine & Industrial Exhaust Gas Turbo

The IHI BBC VTR 161-2 is an axial-flow, heavy-duty exhaust gas turbocharger manufactured under license by Ishikawajima-Harima Heavy Industries (IHI) in partnership with Brown Boveri & Cie (BBC, now ABB Turbocharging). Purpose-built for 4-stroke and 2-stroke medium- and high-speed marine diesel engines as well as stationary power generation units, the VTR 161-2 is engineered to boost engine volumetric efficiency, cut specific fuel oil consumption (SFOC), and operate continuously under harsh thermal gradients.

Independent external/internal lubrication system with self-contained bearing assemblies, the VTR 161-2 delivers long maintenance intervals and high mechanical endurance. Each unit is completely stripped, non-destructive test (NDT) inspected, ultrasonically wall-thickness measured, and dynamically balanced to ISO 1940 Grade G2.5 balance quality limits.

Model Details

• Manufacturer: IHI Corporation under BBC / ABB License
• Base Series: BBC VTR Series (Specification 1 / 2)
• Model Code: VTR 161-2 (Commonly badged as VTR161-2 / VTR 161-2-620)
• Design Type: Axial-flow turbine with single-stage radial/centrifugal compressor wheel
• Lubrication Layout: Self-contained integrated lube oil pumps (gear/slinger type) or engine-fed circuit depending on casing execution
• Turbine Temperature Rating: Up to 620°C continuous / 650°C maximum peak rating

Technical Details

Part Numbers (MPN)

• Complete Unit Assembly: VTR161-2 / VTR-161-2-620 / VTR161-2-HT
• Rotor Shaft Assembly: 161-2-R01 / 008548
• Nozzle Ring: NR-VTR161-2
• Diffuser Ring: DF-VTR161-2
• Blower-End Bearing Assembly: BB-320-VTR161
• Turbine-End Bearing Assembly: TB-380-VTR161

Cross References & Interchangeability

• ABB / BBC: BBC VTR 161, ABB VTR 161-2, VTR 161-11
• IHI: IHI VTR 161-2, IHI-BBC VTR161
• Engine OEM Equivalents: Compatible with Yanmar, Daihatsu, Wärtsilä-Sulzer, and MAN B&W auxiliary engines specified for VTR-160/161 frame sizes.

Compatibility

• Daihatsu: DL-16, DL-19, DL-20, DS-18, PS-20 series
• Yanmar: S165, S185, M200, M220, T220 series
• Wärtsilä / New Sulzer Diesel: 4L20, 6L20, S20 auxiliary engines
• MAN B&W: L16/24, L23/30 series (retrofits and specific build variants)
• ABC (Anglo Belgian Corporation): 6DZC, 8DZC engines
• Akasaka & Hanshin: Various 4-stroke medium-speed marine diesel engines

Our Engineer’s Guide:

1) Pre-Commissioning Bearing Pre-Lubrication

Before starting a newly installed or overhauled VTR 161-2, verify that both the turbine-end and compressor-end bearing sumps are pre-filled to the center of the sight glass with designated turbine lubricating oil. Never rely on residual assembly lubricant. Allow oil to settle for 15 minutes and re-verify static cold levels.

2) K-Value & L-Value Clearances

Always measure and record the axial and radial clearances before tightening the bearing covers:

• Verify axial play with a dial test indicator (DTI) on the shaft end.
• Confirm turbine wheel shroud ring clearance (K-value) and compressor wheel baffle clearances (L-value) against the stamped casing nameplate. Inadequate K-clearance risks catastrophic thermal contact once the exhaust gas pushes past 500°C.

3) Cooling Water Passivation & Post-Shutdown Circulation

Avoid thermal shock. When starting cold engines, run jacket water preheating through the turbocharger casing to reduce thermal stress. When stopping the engine after high-load operations, maintain cooling water circulation for at least 15 to 20 minutes to prevent heat soaking from baking the lube oil in the turbine-side bearing housing.

4) Labyrinth Air Seal Line Verification

Ensure the sealing air connection line taken from behind the compressor impeller or engine air receiver is completely free from carbon, oil mist, or moisture. A clogged seal-air channel allows exhaust gas to cross the turbine labyrinth seal, degrading lubricating oil and causing high bearing temperatures.

Frequently Asked Questions

What is the primary difference between BBC VTR 160 and VTR 161-2?

The VTR 161-2 features internal profile refinements in the compressor wheel and axial turbine blading, optimized gas casing geometry, and updated bearing housing dampers. These enhancements increase total efficiency, improve surge margins under transient loads, and provide higher pressure ratio capability over older 160 variants.

How often should the lube oil and bearings be changed on the VTR 161-2?

For standard ball-bearing arrangements, the lubricating oil in self-contained sumps should be renewed every 1,000 to 1,500 running hours (or strictly in accordance with fuel sulfur specs and oil laboratory analysis). The precision rolling-contact bearings must be replaced between 8,000 and 12,000 running hours depending on engine operational load profiles.

Can this turbocharger handle Heavy Fuel Oil (HFO) operations?

Yes. The IHI BBC VTR 161-2 is designed for Marine Diesel Oil (MDO), Marine Gas Oil (MGO), and Heavy Fuel Oil (HFO / VLSFO) operation. When running on heavy residual fuels, periodic dry-cleaning (nut shell / carbon blasting) or wet water-washing of the turbine and compressor is recommended to prevent nozzle ring encrustation.

What causes cooling water leaks into the exhaust side on this model?

Sulfuric acid dew-point corrosion typically causes casing failures when cooling water temperatures are run too cold (<60°C) with high-sulfur fuel, or when salt/calcium scales build up inside the cooling passages and cause local overheating. We conduct hydraulic testing up to 5.0 bar on every overhauled casing to guarantee internal wall integrity.

Are spare parts like rotor shafts and nozzle rings interchangeable between IHI and BBC/ABB brands?

In most VTR 161-2 executions, core dynamic components such as rotor shafts, blades, nozzle rings, and bearing cartridges are fully interchangeable between genuine IHI and ABB/BBC units bearing the same casing code and specification indices. Always verify the specification code stamped on your unit nameplate before ordering.