Bergen KVMB-12 & KVGB-12 Camshaft

BERGEN KVMB-12 / KVGB-12 CAMSHAFT

The Bergen KVMB-12 and KVGB-12 camshaft is high-precision timing component designed to meet the heavy-duty needs of Bergen K-Series medium-speed 4-stroke marine diesel and gas engines. This camshaft is designed to synchronise the timing of fuel injection pumps, intake valves and exhaust valves with precision to deliver optimum combustion efficiency, maximum power and maritime emissions standards.

The KVMB-12 / KVGB-12 camshaft is produced from premium grade, alloy steel and induction hardened on all working surfaces. It has a segmental, bolt-on design to allow efficient maintenance or single cylinder segment replacements to be made without removing the complete shaft assembly. This element, that is meant to be mounted on marine propulsion plants or auxiliary gensets, can resist severe torsional stress and strong cyclic loads.

Technical Specifications & Model Details

• Engine Series Compatibility: Bergen K-Type (Medium Speed)
• Configuration: Vee (V12 Engine Blocks)
• Manufacturer Part Number (MPN): K-4101-A (Series Core)
• Material Composition: High-tensile forged alloy steel (induction hardened lobes)

Technical Specifications

Key Features

1. Induction Hardened Profiles Cam lobes are induction hardened for a Rockwell hardness rating, resulting in greatly reduced wear on roller lifters for thousands of running hours.
2. Segmental Shaft Design: The segmental design offers an economical overhaul profile where maritime engineers can isolate and replace wear-intensive blocks without a full shaft disassembly.
3. High Torsional Rigidity Heavy-wall structure helps to reduce torsional vibration harmonics from high pressure fuel injection pulses.
4. Dual-Fuel Flexibility: Fully adaptable to both liquid fuel operations (HFO/MDO) under the KVMB designation and lean-burn gas applications under the KVGB profile.

Applications

• Ocean-Going Vessel Propulsion: Main propulsion prime movers for subsea construction boats, anchor handling tug supply (AHTS) vessels, seismic survey vessels and cargo coasters.
• Auxiliary Marine Gensets: High power marine auxiliary generator units for cruise liners and RoPax ferries’ power grid stability.
• Stationary Power Generation: Heavy duty land-based, landward power plants operating in remote or variable grid load settings.

Engine Compatibility

This component is meticulously matched with the legacy and modern architectures of the Bergen 12-cylinder K-Engine family, supporting ratings from 1,000 kW to over 2,250 kW at speeds between 825 RPM and 1,000 RPM.

• Bergen KVMB-12 (Marine Diesel / Propulsion & Aux)
• Bergen KVGB-12 (Lean-Burn Spark-Ignited Gas Engines)
• Inter-operable across variants utilizing standard or specialized high-pressure fuel injection pumps.

Part Number Cross-References

• Bergen / Rolls-Royce Marine Spares Id: PN-702315 / PN-4101-KV12
• Industry Substitutes: BR-K12-CAM-SEG

Marine Engineer Expert’s Guide

From the perspective of a maritime engineer, a metrology issue is keeping the valvetrain on a medium-speed V-engine. Routine overhauls (usually at important milestones of between 20,000 to 40,000 running hours) should always consist of a full examination profile:

1. Pitting and Spalling Inspection: Carefully examine the nose and flanks of the fuel and valve cams. Any sign of micro-pitting or surface spalling suggests the hardened case is damaged which can rapidly accelerate roller degradation.
2. Deflection Measurement Always run a dial indicator along the journal axis before tightening down a segmented assembly. Make that intermediate bearing alignments are within limitations to prevent catastrophic structural stress within the gear case housing.