What’s Common Rail Technology
Posted: 2014-10-14 01:56:22 Hits: 1636
Common rail technology is a method of oil supply that high pressure oil pump, pressure sensor and ECU consist of closed-loop system, separating the production of injection pressure from injection process completely. High pressure oil pump transmits high pressure fuel to public delivery pipe, controlling oil pressure inside public delivery pipe accurately so that pressure in high pressure oil pipe has nothing to do with revolving speed of engine, which can also reduce variation of oil supply pressure in diesel engine due to revolving speed of engine. For that it reduces the flaws of conventional diesel engine. ECU controls fuel injection quantity of oil atomizer. Fuel injection quantity depends on pressure inside fuel rail (public delivery pipe) and the time that solenoid valve opens.
Usages: High-pressure oil pump transmits fuel to public delivery pipe, injecting fuel into cylinders directly by controlling oil atomizer. Common trail separates injection process from oil pressure production completely so that oil supply pressure cannot be affected by revolving speed of engine.
Advantages:
① Flexibility of injection pressure in common trail is adjustable. It can provide the best injection pressure according to different conditions so that can optimize comprehensive performance of diesel engine.
② Common trail can adjust correct time of oil injection independently and flexibly. Cooperating with high injection pressure (120MPa~200MPa), it can restrain NOx and PM locating at a lower numerical value to meet the emission requirements.
③ Control speed variation of oil injection flexibly to realize ideal oil injection rules. Common trail can realize pilot injection and multi injections, which not only can decline NOx produced by diesel engine, but also can ensure excellent dynamic property and economy.
④ Solenoid valve has high control precision on controlling oil injection. Bubbles and zero residual voltage will not occur in high pressure oil-way. Nevertheless, in operating ranges of diesel engine, cycle fuel injection quantity has less variation. Unequal oil supply in every cylinder is improved, which reduces vibration of diesel engine and declines emissions.
