Professional manufacturer Haixing Power analyzes the fuel supply system of diesel generator sets for you

The function of the fuel supply system of the diesel generator set is to store and filter diesel, and inject diesel into the combustion chamber in a specified working order, in a regular, quantitative, and pressure-based manner with the corresponding fuel injection quality, so that it can be mixed and burned with the air quickly and well, and discharge exhaust gas into the atmosphere.

What route does fuel flow through to achieve oil supply and combustion? Let’s explore the specific process with the pair of Haixing Dynamics.

The oil transfer pump sucks the diesel from the fuel tank, filters out impurities through the filter, and enters the low-pressure oil chamber of the fuel injection pump. The fuel injection pump increases the fuel pressure and injects it into the combustion chamber through the high-pressure oil pipe to the fuel injection tube. A very small amount of fuel leaked in the gap between the needle valve and pairs of the injector inside the injector and excessive fuel in the low-pressure oil chamber of the injector pump flow back to the fuel tank through the return pipe. Immediately afterwards, let’s take a look at the relevant knowledge of important components of the combustion system together.

1. What is the function of the fuel injector? What are the requirements for it?

The function of the fuel injector is to atomize the fuel into fine particles and reasonably distribute the fuel into the combustion chamber according to the shape of the combustion chamber to facilitate uniform mixing with the air and promote ignition and combustion.

The requirements for the fuel injector are mainly that the corresponding injection pressure should be provided; the characteristics of the sprayed atomic oil beam must have sufficient range, appropriate injection cone angle and good atomization quality; the injector should be sprayed quickly and in a timely manner, and no dripping occurs.

2. What is the function of the fuel injection pump? What are the requirements for it?

The function of the fuel injection pump is to convey high-pressure diesel to the fuel injector in a regular, quantitative and fixed pressure according to the different working conditions of the engine, in a specified working order. The fuel injection pump of a multi-cylinder diesel engine should ensure that: ① The oil supply of each cylinder is uniform, and the unevenness is not greater than 3% to 5% under the rated working conditions. ② The oil supply is supplied by cylinder according to the operating order of the engine. The oil supply advance angle of each cylinder is the same, and the difference shall not be greater than 0.5° crankshaft angle. ③ To avoid dripping of the fuel injector, the establishment of oil pressure and the stop of oil supply must be quickly.

3. How to adjust the oil supply advance angle of the fuel injection pump?

There are two ways to adjust the oil advance angle of the fuel injection pump: (1) Adjust the coupling, or change the relative angle position between the fuel injection pump camshaft and the diesel engine crankshaft through the oil advance angle automatic adjuster. (2) Change the height of the roller lifting column, thereby changing the moment when the plunger closes the oil inlet hole in the plunger sleeve, so that the oil supply spacing angles of the multi-cylinder engine are equal.

4. What is the function of the speed regulator?

The function of the speed regulator is to enable the diesel engine to automatically adjust the fuel supply as the external load changes, so that it can automatically stabilize the idle speed; limit the engine speed and prevent overspeeding; under normal engine operating conditions, the two-speed speed regulator is directly operated by the driver to control the fuel supply, and the full-speed speed regulator can automatically control the fuel supply to maintain the stable speed; when there is a correction device, the engine torque characteristics can be corrected in full-load operating conditions and improve the adaptability of instantaneous overload.

5. The composition and function of the speed stabilizer device in the speed regulator.

The speed stabilization device consists of a pin rod, a spring, adjusting nut, lock nut and sheath. Its function is to buffer and stabilize the speed when the oil supply tooth rod suddenly returns to the idle oil supply position, so as to avoid the tooth rod reducing oil due to inertia, causing the idle speed to be unstable, and even the engine is shut down.

6. What is the function of the fuel injection pump coupling? What types are there?

The function of the fuel injection pump coupling is to transmit the power between the drive shaft and the fuel injection pump camshaft; the deviation of the coaxiality between the two shafts during installation and the use of a small amount of relative angular displacement between the two shafts to adjust the fuel supply timing of the fuel injection pump. Couplings are commonly used in rigid cross-bakelite disc couplings and flexible steel sheet couplings.

7. What is the function of the automatic oil supply advance angle regulator?


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