Operation Section
1
–
88
9.3 Higher Injection Pressure, Optimized Injection Rates, Higher Injection
Timing Control Precision, Higher Injection Quantity Control Precision
(1) Higher Injection Pressure
• The fuel that is injected from the nozzle turns into finer particles as the fuel injection pressure increases. This improves
combustion and reduces the amount of smoke contained in the exhaust gases. Initially, the maximum injection pres-
sure of the in-line pump (A type) and the distributor pump (VE type) was 60 MPa. Due to advancement in high-pres-
sure applications, there are some recently developed fuel injection systems that inject fuel at a pressure of 100 MPa
or higher. The second-generation common rail system injects fuel at an extremely high pressure of 180 MPa.
(2) Optimized Injection Rates
• The injection rate is the ratio of the changes in the fuel quantity that is injected successively from the nozzle within a
given unit of time.
Q000920E
50
Common Rail Series
100 150 200
185
145
120
120
ECD V Series
Mechanical Pump
Injection Pressure
(
MPa
)
A Type Pump
Distributor Type Pump
NB Type Pump
ECD V4 Pump
HP0Pump
HP2Pump
HP3,4Pump
ECD V3 Pump
(1st Generation)
(2nd Generation)
1 MPa is
approximately 10.2kgf/cm
2
t
Injection Rate
High Injection Rate
Injection Quantity
Q000921E
To Next Page
Loading...
