Excess diesel oil returns to the fuel tank through the low-pressure pipe, and other diesel oil is compressed to high pressure by the fuel injection pump), enters the fuel injector through the high-pressure oil pipe, and is directly injected into the combustion chamber of the cylinder for compression combustion.
In order to make the diesel engine work stably at idle speed and limit the overspeed of diesel engine, there is also a governor on the fuel injection pump. Fuel injection pump is the most precise component in the fuel supply system of diesel engine. Its function is to adjust the amount of diesel oil according to the change of diesel engine working conditions, improve the pressure of diesel oil, and supply diesel oil to the injector according to the specified time and law.
Extended data:
trait
1, high energy density (the effective thermal efficiency of large low-speed turbocharged diesel engine has exceeded 50%) and low fuel consumption rate, which are very important for saving energy and improving economic benefits.
2. Good fuel economy;
3. Less greenhouse gas emissions, and its carbon dioxide emissions are about 30-35% lower than those of gasoline engines. However, the waste gas contains more harmful components (NO, particulate matter, etc. ) and the noise is large, which has attracted attention in environmental protection.
4. The power and speed range is very large (power 1-65580 kW, speed 54-5000 r/min), so it has a wide range of applications.
5. The structure is complex, the material and process requirements of parts are higher, the manufacturing cost is higher, and the quality is higher than that of gasoline engines.
6. New technologies (electronic control, supercharging, waste gas recycling, new materials) have been widely used and developed rapidly. Product research and development and production equipment investment is large, belonging to technology-intensive and capital-intensive products.