The SAC volume refers to the small space within the fuel injector between the valve seat (fuel shut-off point) and the entrance to the final metering orifice.

• This volume holds fuel that vaporizes incompletely at the end of injection and enters the cylinder at low velocity during the expansion stroke.
• The unburnt fuel contributes to post-injection dripping, after-burning, and increased emissions such as unburnt hydrocarbons and NOx.

Low SAC volume injectors are introduced to address these issues:

• Minimize post-injection dripping and after-burning.
• Reduce carbon accumulation on the nozzle tip and prevent heat sinking of the nozzle, which can cause damage.
• Improve fuel combustion, lowering emissions and enhancing engine efficiency.

Additionally, nitriding treatment of the fuel valve enhances heat resistance and improves durability against corrosion, thereby prolonging service life. This directly contributes to an improved Life Cycle Value (LCV) of the engine.

Precise regulation of fuel valve opening pressure helps in optimal combustion. Higher opening pressure improves fuel atomization, leading to more complete combustion. This improved combustion helps in:

• Firstly, it reduces smoke density, particularly at low engine loads, minimizing particulate emissions and improving engine efficiency.
• Secondly, it minimizes carbon deposits within the combustion chamber, reducing the risk of pre-ignition and engine damage.

The cleaner combustion process extends the life of engine components such as pistons, exhaust valves, and the combustion chamber itself, ultimately contributing to a higher LCV through extended service intervals and reduced maintenance.

• Contaminates turbocharger which leads to premature failure of Turbocharger
• Excessive wear of liner & piston rings causing blow past.
• Burning of piston crown.
• Blockage of exhaust valves & exhaust passages.
• Emissions trouble & air pollution.

• High wear rate of liner, bearings, piston rings.
• Reduction in load carrying capacity.
• Improper lubrication & cooling.
• Bacterial attack.
• Corrosion.

All these will impact the life cycle value of the engine.