Diesel generator set belongs to mechanical equipment, in the long-term operation is often prone to shortcomings, the common method of identifying shortcomings is to listen, look, check, relatively simple and direct method is to identify through the generator dynamic and static, and can eliminate small shortcomings through static and static, in order to avoid the occurrence of serious shortcomings.
First, the diesel engine of the diesel generator set is working at low speed (idle speed), and the metal knocking sound of “bar da, bar da” can be obviously heard beside the valve chamber cover. This kind of movement is caused by the collision between the valve and the rocker arm. The primary reason is that the valve space is too large. Valve clearance is one of the primary skill indexes of diesel engine. The valve space is too large or too small, the diesel engine can not operate normally. The valve open space is too large, the displacement between the rocker arm and the valve is too large, and the impact force of the contact is also large, so the metal knocking sound of “bar da, bar da” is declared. This kind of noise often occurs after the engine is operated for a long time. Therefore, the valve open space should be readjust every 300h or so.
Two, the diesel engine of diesel generator set sudden drop to low speed from high speed operation, in the upper part of the cylinder can significantly hear the “when, when, when” bump sound. This is often one of the shortcomings of the diesel engine, the reason is that the main piston pin in the open space between the connecting rod bushing is too large, the engine speed mutations and a lateral dynamic imbalance, leading to the piston pin in the connecting rod bushing rolling together to swing to the left and right, so that the piston pin hit the connecting rod bushing and the announcement of movement. In order to avoid the occurrence of greater shortcomings, constitute unnecessary waste and economic loss, should be timely replacement of the piston pin and connecting rod bushing, and then ensure that the diesel engine can operate normally and effectively.
Three, the diesel engine operation of the diesel generator set can be heard in the lower part of the diesel engine body, a heavy, dull knocking sound, especially in the diesel engine high load operation, this movement becomes more significant. This kind of movement is because of the abnormal friction between the contact between the crankshaft spindle tile or the crankshaft spindle bearing and the spindle neck. The primary reason is that the space between the crankshaft spindle neck and the spindle tile or the crankshaft bearing is too large, which constitutes the uneven wear between the spindle neck and the crankshaft spindle bearing or the spindle tile leading to the abnormal friction and the heavy, dull knocking sound. After hearing this kind of noise, the operation of the diesel generator set should be interrupted immediately, because if the diesel generator set continues to operate without inspection and repair after this kind of noise, it is likely to appear the phenomenon of “holding tile” and “burning shaft”. In order to avoid such a severe incident, should be immediately interrupted operation, check whether the spindle tile bolt loose, if not should be unloaded crankshaft and spindle bearing or spindle tile, measured by professionals, calculate the value between them, and the rules of the data, and together to check the wear of the spindle and tile shaft, should be repaired or replaced if necessary.
Four, the engine operation in the upper part of the cylinder can clearly hear a piston on the cylinder of the crisp knocking sound, is we often say “knock cylinder”. The root cause of this shortcoming is that the injection advance Angle of diesel engine is too small. As we all know, the oil supply advance Angle of diesel engine is one of the primary skill data of diesel engine. Whether the oil supply advance Angle is correct or not will directly affect whether the diesel engine can operate normally, and whether the engine can supply normal power, and affect the operation of the whole machine. In order to make the composition of the mixture and the combustion process can proceed normally, it is necessary for the diesel engine to have a certain injection advance Angle, the injection advance Angle is too small, the air injected into the cylinder constitutes the combustible gas combustion, and then leads to the combustion instability, the lateral deviation occurs in the upward stage of the piston and the cylinder wall contact knocks, and the cylinder body knocks.
Five, diesel engine sudden change load can be heard in the body near a dull knocking sound. This mainly comes from the abnormal friction between the crankshaft connecting rod journal and connecting rod tile, the primary reason is because the open space between the connecting rod journal and connecting rod tile is too large, caused by partial pulsation. The mechanism of such movement and repair detection method is exactly the same as that of spindle and spindle tile, which will not be introduced in detail here.
Six， On the front cover of the diesel engine, a sound of “howling” could be clearly heard. This kind of movement comes from the meshing gear inside the front cover. The gear of each part of the meshing gear is worn too much, which causes the open space of the gear to be too large, so that the gear can not enter the normal meshing situation. The method of removing this movement is to open the front cover, check the meshing situation of the gear with lead sheet or paint, and adjust it.
Seven， The violent knock sound is heard along the whole length of the diesel engine cylinder, especially at low speed or speed changes. The main reason for this phenomenon is excessive wear of the piston and the cylinder, so that the open space of the piston and the cylinder is too large. When the piston is going up or down, the piston moves sideways in the cylinder, and shakes, and the cylinder wall contact makes the wear worse, and declares the dumb resistance sound. After this phenomenon should find professional personnel to determine the cylinder liner and piston, if necessary, replace the new piston or cylinder liner.
Eight, along the diesel engine cylinder of the diesel generator set are similar to the movement of tapping the anvil with a small hammer. The primary reason for this movement is that the open space between the piston ring and the ring groove is too large, so that the piston ring and the piston knock when working up and down, which is similar to the movement of tapping an anvil with a small hammer. In this case, the operation of the engine should be interrupted and a new piston ring should be replaced.
Nine, a collision of objects can be heard in the upper part of the cylinder. The main reason for this kind of movement is that the valve and the piston collide with each other. The main reason for this phenomenon is that the valve is not suitable, which leads to the valve and the piston high-speed violent collision when the piston works to top dead center. At this time, the diesel engine operation is weak, and the mechanical anti-load capacity decreases significantly. The detailed method to eliminate this shortcoming is to raise the cylinder pistons to TDC in sequence, press down on the valve, check for open space between the piston and the valve, and readjust the valve.
Jiangsu Meao Power Technology Co., Ltd. is an important manufacturer of diesel generators. The company mainly manufactures and sells diesel generator sets with power of 3-3000kW, mobile power station of 24-600kW, Marine emergency diesel generator set of 24-800kW, gas generator set, heavy oil generator set and all kinds of imported series, special series (trailer, static speaker, mobile lighthouse, container, etc.) diesel generator At the same time, we are engaged in generator set maintenance and after-sale service of generator set accessories.
