Fuel System Components
Advanced HEUI™ Technology by Caterpillar Yields Higher Performance
Caterpillar introduced its Hydraulically Actuated Electronically Controlled Unit Injector (HEUI) in 1993. This achievement is recognized as one of the most significant advancements in diesel engine technology of the last century. HEUI uses engine oil pressure to power high-pressure fuel injection in diesel engines so injectors are no longer camshaft operated.
HEUI surpasses many of the limitations of mechanical and conventional electronic injectors, and sets new standards for fuel efficiency, reliability and emission control.
Precise Control of Fuel Metering and TimingAvailable as standard equipment on an ever-widening range of Cat Engines and machines, the highly sophisticated HEUI system uses hydraulic energy instead of mechanical energy to operate fuel injectors. Working in tandem with the engine’s ECM (Electronic Control Module), the HEUI system provides extremely precise control of fuel metering and timing, resulting in unmatched engine performance and economy.
In the traditional common rail fuel system, for example, the entire fuel line is under high pressure. With the HEUI system, fuel remains at low pressure until it is injected into the cylinder. Fuel pressure is created hydraulically in response to a signal from the Electronic Control Module (ECM). Because HEUI controls injection pressure electronically it is completely independent of crankshaft speed. Peak injection pressure can be achieved under acceleration and lug conditions, providing better fuel economy, better response and reduced smoke.
HEUI injector technology is changing the way equipment owners, technicians and operators think about diesel engine performance bringing new value to your investment in Cat engines and machines.