11 wrong operation methods of diesel generator(1) the load operation of the non warmer after cold start
When the diesel engine cooler is started, because of the poor oil viscosity and poor fluidity, the engine oil pump is deficient in oil supply, and the machine friction surface is badly worn because of poor oil lubrication. Therefore, the diesel engine should be heated at idle speed after cooling, and the engine oil temperature reaches more than 40 centigrade. The machine should start with low speed gear and run a mileage in every position in sequence until the oil temperature is normal and the oil supply is full, then it can turn to normal driving.
2) operation of diesel engine when oil is insufficient
At this time, due to insufficient oil supply, the friction surface of each pair of friction pairs is insufficient, resulting in abnormal wear or burn. For this reason, the engine must ensure sufficient oil before starting and during the operation of the diesel engine, so as to prevent the failure of cylinder and tile burning due to lack of oil.
(3) shut down immediately after loading or emergency loading.
After the diesel engine is extinguished, the cooling system water circulation stops, the heat dissipation capacity is drastically reduced, the heating parts are lost and the parts of the cylinder head, cylinder liner and cylinder body are overheated, and the cracks are produced, or the excess expansion card of the piston is killed in the cylinder sleeve. On the other hand, when the diesel engine is shut down without cooling, it will cause the friction surface to be insufficient. When the diesel engine starts again, it will cause more wear due to poor lubrication. Therefore, the diesel engine should be disloaded before firing and gradually reduce the speed and load for several minutes.
Hot throttle after cold start of diesel engine (4)
If the valve is throbbing vigorously, the speed of the diesel engine will increase sharply, which will cause some friction surfaces on the machine to wear violently due to dry friction. In addition, the piston, connecting rod and crankshaft receiving force change greatly during the throttle, causing violent impact and easily damaging the machine parts.
(5) running under the condition of insufficient cooling water or high temperature of cooling water and oil.
The insufficient cooling water of the diesel engine will reduce the cooling effect. The diesel engine overheat because of the lack of effective cooling; the high temperature of the cooling water and oil will also cause the diesel engine to overheat. At this time, the main heat load of cylinder head, cylinder liner, piston assembly and valve and so on is big, its mechanical properties such as strength and toughness drop sharply, which makes the parts deformation increase, reduce the gap between parts and speed up the wear of the machine parts. The high temperature of cooling water and oil will accelerate the deterioration and burning of the oil, and the viscosity of the oil decreases. The condition of the lubrication of the cylinder and the piston and the main friction pairs will deteriorate, and the abnormal wear is produced. The overheating of diesel engine will also deteriorate the combustion process of diesel engine, resulting in abnormal operation of injector, poor atomization and increased carbon deposition.
(6) running under the condition that the cooling water and oil temperature are too low.
During the working process of the diesel engine, the temperature of the cooling water is too low and the temperature of the cylinder wall decreases. The water vapor produced by the combustion is condensed into water, and the acid is formed by contact with the exhaust gas and attached to the cylinder wall to produce corrosion wear. It is proved by practice that the diesel engine is often used in the cooling water temperature of 40 ~50 C, and the wear of its parts is several times more than that of the normal working temperature (85 ~ 95). At this time, the temperature in the cylinder is low when the temperature is too low, the ignition delay period of the diesel engine is prolonged, and the pressure of the diesel engine increases rapidly as soon as the ignition is caught, and the engine fuel is rough, and the mechanical damage of the parts is easily caused. The diesel engine runs in the low temperature of cooling water for a long time, the gap between the piston and the cylinder sleeve is large, the phenomenon of the cylinder knocking has occurred, and the vibration is produced, which causes the cavitation erosion of the cylinder sleeve. The oil temperature is too low, the oil viscosity is poor fluidity, the oil quantity of the lubricating part is insufficient, the lubrication is worse, the wear of the friction pair is increased and the service life of the diesel engine is shortened.
(7) operation under low oil pressure
If the oil pressure is too low, the lubrication system can not carry out normal oil circulation and pressure lubrication, and the lubricating parts can not get enough oil. Therefore, the machine should pay attention to the oil pressure gauge or the oil pressure indicator when driving. If the oil pressure is lower than the specified pressure, stop immediately and continue to run after troubleshooting.
8) machine overspeed and overloading
If the machine is overspeed and overloading, the diesel engine will operate under the condition of excessive load and high speed. It is easy to cause rough work. The heat load and mechanical load of cylinder sleeve, piston, connecting rod and so on are increased, and the failures of cylinder, burning and so on are easy to happen. Heavy overload often causes rough combustion in the cylinder for a long time, which easily damages the cylinder gasket.
Bombardment of the throttle before flameout (9)
If the high speed diesel engine is suddenly stopped running, its huge inertia will damage the parts of the crank and connecting rod mechanism and the gas distribution mechanism, and shorten the service life. At the same time, the throttle is caused by excessive fuel entering the cylinder, which is not fully burned and flows down the cylinder wall to dilute the lubricating oil. In addition, the piston, valve and combustion chamber deposit will increase significantly, resulting in nozzle blockage and piston clamping.
(10) when the diesel engine temperature is too high, suddenly add cooling water.
If a sudden cooling water is added to the diesel engine when it is short of water and overheating, cracks will occur in the cylinder head, cylinder liner and cylinder block. Therefore, when the temperature of the diesel engine is too high, the load should be removed first and the speed is raised a little. The diesel engine is extinguished after the water temperature drops, and the water radiator cover is loosened and the water vapor is eliminated. If necessary, the cooling water can be injected slowly into the water radiator.
Long run idle speed (11)
When the diesel engine is idle, the lubricating oil pressure is low and the injection cooling effect on the top of the piston is poor, resulting in a sharp increase in wear and tear, easy to pull in the cylinder, and can also cause bad atomization, incomplete combustion, serious carbon accumulation, and sometimes even lead to valve and piston ring death and cylinder liner cavitation erosion. For this reason, some diesel engine instructions clearly stipulate that the idle time of diesel engines should not exceed 15 ~ 20min.