Influence of "Outlet Quantity" of Multi-Cylinder Diesel Engine on the Stability of Multi-cylinder Diesel Engine and Its Countermeasures

In recent years, the driver of the injection pump calibration requirements are getting higher and higher, in addition to strong power, acceleration performance is good, the stability of multi-cylinder diesel engine requirements are higher. Of course, many factors affect the smoothness, this article only on multi-cylinder diesel injector needle valve "oil" unevenness on the stability of the impact are described. In the fuel pump test bench for testing and adjusting the fuel injection pump injector is called a standard injector, according to the relevant standards, the standard fuel injector error should not exceed 1%; and for injection on the diesel engine Device, the error of oil to allow larger, the general requirements of not more than 5%. But currently on the market for the needle and pin parts installed into the injector, the oil output error has exceeded this standard. I had used the same plunger without governor with the same speed, the same number of fuel injection on the two plants produced models ZS15S15 and CN-DN15S15 needle valve parts each 30 after the installation of the injector Test, measured the error of up to 10% of oil. Such a big error, even if the fuel injection pump cylinder adjusted quite evenly, the actual amount of diesel into the cylinder fuel will be uneven, which affects the stability of the diesel engine. Here's an example. Xiaogan City, Hubei Province, Xihe Yin driving a Hwacheon agricultural vehicles, diesel engine model 490Q (D), with the No. 1 injection pump, injection pump is calibrated with a standard injector. The old driver experienced, he always sounds a bit diesel sound problem. Later on the test bench with a standard injector to review the fuel pump, the result is all normal; but with the diesel engine on the test bench inspection and found that a cylinder cup less fuel, indicating that the cylinder fuel injection Needle valve parts out of fuel. After replacing the needle valve, the diesel engine's sound is normal. In view of the above, so some places in Hubei Province changed the method of adjusting fuel injection pump. That is, without the standard test rig injector, but the diesel injector directly on the test bench to adjust the fuel pump. Of course, before the fuel injector on the test bed, you must first test on the injector to do the three project test adjustments: First, the injection pressure adjustment; second atomization test, including atomization fineness, atomization uniformity And atomization cone angle test; third is dry crispness test. Using the diesel engine's own fuel injector to adjust the fuel pump, you can use the fuel pump with a large amount of fuel to match the small sub-pump oil volume adjustment, and the small amount of fuel injector matching pump oil Large amount of adjustment method, so that the diesel cylinder fuel into the cylinder evenly. It is important to note that the injectors must be fitted with a diesel engine in the order they are placed on the test bench. To prevent mistakes, you can mark the injector. This calibration out of the fuel injection pump and fuel injector, diesel engine is not only stable, dynamic and economic Ye Hao. However, this method of adjustment also has a problem. Because the injector needle and valve parts are consumable parts, once burned and replaced, the performance of the diesel engine may not be so good, because the needle and valve parts of the oil is likely to be different, resulting in diesel engine cylinder oil is not Uniform, affecting diesel engine performance. This can also give an example to illustrate this issue. Dongshenghu Farm in Wuhan City, Hubei Province, Lee driving a Dongfanghong -75 tractor, the diesel engine is equipped with 802-type fuel pump. The fuel injection pump is directly used in diesel engine test bench on the injector calibration. In a period of time after adjustment, diesel engine running smoothly, strong power and fuel-efficient. Later, an injector needle valve due to burn and replace the diesel engine was obviously insufficient, and the stability is poor. In the test bench with a standard fuel injector injector check, the uneven amount of oil in each cylinder, and one of the cylinder significantly less fuel. Obviously, this is because the original needle that was burned out of the oil is too large, so can only pump the fuel pump to adjust the oil volume is small, so that the cylinder oil evenly, but later replaced by the couple There is no big oil out of the original, so the cylinder of the oil is obviously less than normal. After obtaining the driver's consent, the test bench with a standard fuel injector to re-tune the fuel pump, and replaced the four out of a consistent needle valve, the diesel engine will return to normal (I usually diesel engine spray Oil needle valve coupling after the determination of the amount of oil labeled). The last debugging method used in the above example is both the author usually used method, which is exactly what we want to recommend this article, are described below. In the test bench with a standard fuel injector pump to adjust to the specification. At this moment, the fuel injection pump is not to be removed from the test bench at the moment, and the standard injector of the test bench is removed from the oil collecting cup, a homemade mist eliminator is placed in the oil collecting cup, The needle valve fitted as a fuel injector. In the injector tester after passing the test, connected to the test tube with a high-pressure tubing, will be connected to the high-pressure tubing injector placed in the test set collector cup mist eliminator, and the other end of the high-pressure tubing Fuel injection pump connection. Start the test bench to check the fuel quantity of each working condition and observe whether the cylinders are consistent. If they are inconsistent, replace the fuel injectors of cylinders with less fuel with each other until the fuel quantity of each cylinder is basically the same. In other words, the fuel injector to offset the error to adjust the fuel pump specifications within the provisions of the fuel supply error. Such a good injection pump and injector, the actual amount of oil into the cylinder is fairly uniform, the performance of the diesel engine is also very good, especially the excellent stability. Finally, I make a suggestion and introduce a concept. I suggest that manufacturers can be the same amount of fuel injector needle valve unit package, which is a good thing for users, such as a drag production of 802 and No. II injection pump plunger clutch package is very Welcome by users. If you do not group, then the needle valve should be the amount of oil error down to a certain range. In addition, I was thinking of a fuel injector tester that measures the amount of oil, because it is less convenient to measure the fuel injector output on the fuel pump test bench. I intend to use idle pump modified into both manual, but also electric, both traditional injector tester function, but also determine the new test device for oil production.