Common Rail system

In this system, the fuel 15 pumpedhy single high pressure mid-cylinder pump into a common rail or header through likens and low pressure or transfer pump. The pressure
on the common rail ls controlled by the relief valve which is kept constant. Due to the high pressure in common rail, the fuel is forced to ciao. of the nozzle located in the cylinders. A metered quantity of fuel is supplied to each cylinder through nozzle by operating their fuel injection values with the help of cam mechanism driven by the crankshaft of the engine.

Advantages

Only one pump is sufficient for multi-cylinder engines.
System is simple to construct and also for maintenance.
Less maintenance cost.
Variation in pump supply pressure will alfect all the cylinders uniformly.
It fulfills the requirements of either

constant load with variable speed

constant speed with variable load

Disadvantages

System requires very accurate design and workmanship.
Possibility of leakages m injection valves

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