Principle and structure of HEUI injector system for C9 engine of Caterpillar 336D excavator

Principle and structure of HEUI injector system for C9 engine of Caterpillar 336D excavator

HEUI has four functions. The HEUI injector pressurizes the supplied fuel from 450 kPa (65 psi) to 175 MPa (25382 psi). The HEUI injector functions as an atomizer by allowing high-pressure fuel to flow through the orifice at the tip of the unit injector. The HEUI injector sends the correct amount of atomized fuel into the combustion chamber and sprays the atomized fuel evenly in the combustion chamber.