Introduction to Diesel Generator Set Accessories--Fuel Injection Pump

Diesel engines are assembled by many important components, mainly composed of a body, two major mechanisms (crank and connecting rod mechanism, valve mechanism), and four major systems (fuel supply system, lubrication system, cooling system, and starting system). In this article, the generator manufacturer, Dingbo Power will introduce you to the fuel injection pump, an important component of the fuel supply system.

1. The role of fuel injection pump of diesel generator set:

(1) Increase oil pressure (constant pressure): Increase the injection pressure to 10MPa～20MPa.

(2) Control the fuel injection time (timing): fuel injection and stop fuel injection at the specified time.

(3) Control the amount of fuel injection (quantitative): According to the working condition of the diesel engine, change the amount of fuel injection to adjust the speed and power of the diesel engine.

2. The requirements of diesel generator sets for fuel injection pumps

(1) The fuel is supplied according to the working order of the diesel engine, and the fuel supply of each cylinder is even.

(2) The fuel supply advance angle of each cylinder should be the same.

(3) The oil supply duration of each cylinder should be equal.

(4) Both the establishment of oil pressure and the stop of oil supply must be rapid to prevent the occurrence of dripping.

3. The classification of diesel generating set fuel injection pump

(1) Plunger injection pump.

(2) Pump-injector type, which combines the fuel injection pump and the fuel injector.

(3) Rotor-distributed fuel injection pump.

4. The structure of the fuel injection pump of a typical diesel generator set

The commonly used diesel fuel injection pumps in our country are: A-type pump, B-type pump, P-type pump, VE-type pump, etc. The first three are plunger pumps; VE pumps are distributed rotor pumps.

(1) Structural characteristics of B-type fuel injection pump

a. Spiral groove plunger and flat hole plunger sleeve are used;

b. The oil volume adjustment mechanism is a rack rod type, with an adjustable maximum oil volume rigid limiter (some use spring limiter) at the front end of the rack rod;

c. Adjusting screw-type roller body transmission parts;

d. The camshaft is a tangential cam and is supported on the housing by tapered roller bearings.

e. The pump body is integral and adopts independent lubrication. 

(2) Structural characteristics of P-type fuel injection pump

a. Suspension type sub-cylinder assembly the plunger, plunger sleeve, delivery valve and other parts are fixed together with a steel sleeve of the sub-cylinder with a flange plate to form      an assembly part. It is directly fixed on the shell with pressed gold studs to form a suspended structure. The sleeve can be rotated at a certain angle.

b. Adjusting the oil supply of each sub-cylinder. The flange of the sub-cylinder steel sleeve has an arc groove. Loosen the compression stud and rotate the steel sleeve. The plunger        sleeve of the sub-cylinder will rotate to a certain angle with it. When the oil return hole is positioned relative to the upper chute of the plunger, the oil return time changes.

c. The adjustment of the start point of the oil supply of the sub-cylinder increases or decreases the gasket under the flange sleeve to make the oil inlet and return holes of the plunger sleeve move up and down slightly, thereby changing the position relative to the upper end of the plunger. Starting point of oil supply.

d. Ball pin angle plate type oil volume adjustment mechanism is welded with 1~2 steel balls on the end of the transmission sleeve, the cross section of the oil supply rod is angle steel,     and the horizontal right angle side is opened with a small square notch, which is a square groove when working. Engage with the steel ball on the transmission sleeve. Non-adjustable     roller body transmission parts;

e. Fully-enclosed box-type pump body It adopts an integrally sealed pump body without side windows, and only has an upper cover and a lower cover. The pump body has high rigidity      and can withstand higher injection pressure without deformation, so that the life of the plunger and even parts is longer;

f. Adopt pressure lubrication method; 7. There is a special pre-stroke inspection hole. There is a screw plug above the roller body. This hole can be used to check whether the pre-stroke    of each sub-cylinder is consistent (measured with a special instrument).

The above are information about the components of Diesel Generator Set produced by Guangxi Dingbo Power Equipment Manufacturing Co., Ltd. Dingbo Power is a diesel generator set manufacturer integrating the design, supply, commissioning and maintenance of diesel generator sets. If you are interested to know more, please cotact us by email dingbo@dieselgeneratortech.com.