Tier4 technology

Training KOMTRAX analysis Tier4 technology Operating tips Maintenance tips

Komatsu interim tier 4 engine technology

Based on Komatsu proprietary technologies developed over many years, the new diesel engine reduces exhaust gas particulate matter (PM) by more than 90% and oxides of nitrogen (NOx) by more than 45%—when compared to current Tier 3 levels—while still consuming less fuel.

Komatsu’s Tier 4 engine technology includes:

  • Newly designed variable geometry turbocharger
  • Newly designed DPF (diesel particulate filter)
  • Heavy duty HPCR (high-pressure common rail) fuel injection system
  • Larger more robust cooled EGR (exhaust gas recirculation) system
  • Redesigned combustion chamber at top of piston
  • Harmonized engine and machine interface by electronic control system
Tier 4 engine

Komatsu has integrated this Tier 4 technology into construction and mining engines ranging in size from 3.3- to 46-liter2. Through Komatsu’s in-house development and production of engines, hydraulic units, control systems and major components, the company has attained exceptional machine performance under a variety of operating conditions. Komatsu customers have come to expect outstanding quality and performance, and these Tier 4 powered machines are designed to meet customer expectations while improving the environment and fuel consumption.

1. Variable Geometry Turbo System

A newly designed variable geometry turbocharger features Komatsu proprietary technology that varies the air-flow and delivers optimum air quantity to the engine combustion chamber under all speed and load conditions. The result is cleaner exhaust gas and improved fuel economy while maintaining power and performance.

Variable Geometry Turbo System
Komatsu Diesel Particulate Filter

2. Diesel Particulate Filter

Komatsu has designed and developed a high efficiency diesel particulate filter that captures more than 90% of PM. Passive and active regeneration is initiated automatically by the engine controller as needed to burn the particulates while the engine is running allowing uninterrupted machine operation. A special oxidation catalyst with a fuel injection system eliminates the need for a traditional fuel burner thereby reducing maintenance costs and increasing reliability.

3. Heavy Duty HPCR (High-Pressure Common Rail) System

Computer controlled heavy duty HPCR system delivers a precise quantity of pressurized fuel into the engine combustion chamber using multiple injections to achieve complete fuel burn and reduce exhaust emissions. Fuel injector life has been improved through the use of ultra-hard wear resistant materials such as diamond-like carbon.

4. Heavy Duty Cooled EGR (Exhaust Gas Recirculation) System

Cooled EGR, a technology well-proven in existing Komatsu engines, has increased capacity to further reduce NOx to Tier 4 levels. Larger more robust components ensure reliable performance during the demanding work conditions of construction equipment.

5. New Combustion System

The fuel/air combustion chamber located at the top of the engine piston has a new shape designed to improve combustion and further reduce NOx, PM, fuel consumption and noise.

6. Electronic Control System

The engine and machine work equipment function in harmony as the electronic control system performs high-speed processing of information from sensors throughout the machine. The result is reduced fuel consumption, noise, NOx and PM.

1 All comparisons are to Tier 3 diesel engine emission regulations.
2 Including some engine models which are jointly developed and manufactured by Cummins Inc.