Analysis of 11 kinds of wrong operation methods of diesel generator
2021-08-19
Diesel generator set is a kind of power supply equipment with diesel engine as prime motor, driving synchronous generator to generate electricity. This is a kind of power generation device with rapid starting, convenient operation and maintenance, less investment and strong adaptability to the environment. Now the application of generators is more and more widely, so in the process of use and operation, it is certain to encounter a variety of faults. The following is a brief introduction of 11 wrong operation methods of diesel generators:
(1) After cold start, the machine will run with load without heating
When the cold engine of diesel engine starts, due to the large viscosity of oil and poor fluidity, the oil supply of the oil pump is insufficient, and the friction surface of the machine is poor due to the lack of oil, resulting in sharp wear, and even the failure of drawing cylinder and burning tile. Therefore, after cooling and starting, the diesel engine should run at idle speed to heat up, and then run with load when the oil temperature reaches more than 40℃; The machine should start at a low speed and drive in each gear step by step for a distance until the oil temperature is normal and the oil supply is sufficient, then it can turn to normal running.
(2) The diesel engine runs when the oil is insufficient
At this time, due to insufficient oil supply, the surface of the friction pair will be insufficient oil supply, resulting in abnormal wear or burn. For this reason, before the machine starts and the diesel engine running process to ensure that the oil is sufficient, to prevent the lack of oil caused by cylinder, burning tile failure.
(3) Stop immediately after emergency stop with load or sudden unloading of load
After diesel engine flaring out, the circulation of cooling water stops, the heat dissipation ability decreases sharply, and the heated parts lose cooling, which is easy to cause the cylinder head, cylinder liner, cylinder block and other parts to overheat, crack, or make the piston over-expansion stuck in the cylinder liner. On the other hand, when the diesel engine is shut down without idle cooling, the friction surface will contain insufficient oil, and when the diesel engine starts up again, it will aggravate the wear due to poor lubrication. Therefore, the diesel engine should be unloaded before extinguishing, and gradually reduce the speed, no load running for a few minutes.
(4) After the cold start of the diesel engine, bang the throttle
If you bang the throttle, the speed of the diesel engine increases sharply, which will cause some friction surfaces on the machine to produce dry friction and severe wear. In addition, when the piston, connecting rod and crankshaft handle force changes, causing violent impact, easy to damage parts.
(5) In the case of insufficient cooling water or cooling water, oil temperature is too high operation
The lack of cooling water will reduce the cooling effect of diesel engine, and the engine will overheat because of the lack of effective cooling. The oil temperature of cooling water and oil is too high, which will also cause the diesel engine to overheat. At this time, the cylinder head, cylinder sleeve, piston components and valves are mainly subjected to heat load, its mechanical properties such as strength, toughness and other sharp decline, increase the deformation of the parts, reduce the coordination gap between the parts, accelerate the wear of the parts, and serious cracks and stuck parts of the fault. The high temperature of cooling water and oil will accelerate the aging deterioration and burning of oil, and the viscosity of the machine oil decreases, and the condition lubrication condition of the liner and piston and the main friction pair deteriorates, resulting in abnormal wear. Diesel engine overheating will also worsen the combustion process of diesel engine, make the injector work out of order, poor atomization, carbon accumulation increase.
(6) In the cooling water and oil temperature is too low state operation
During the operation of diesel engine, the temperature of cooling water is too low, and the temperature of cylinder wall decreases accordingly. The water vapor produced by combustion condenses into water droplets, which contact with exhaust gas and generate acidic substances, which adhere to the cylinder wall and produce corrosive wear. Practice has proved that when the cooling water temperature of diesel engine is usually 40℃~50℃, the wear of its parts is several times larger than that under the normal working temperature (85℃ ~ 95℃). At this time, the temperature in the cylinder is too low when the water temperature is too low, the ignition delay period of the diesel engine is prolonged, once the fire, the pressure rises rapidly, the diesel engine fuel is rough, and it is easy to cause mechanical damage to the parts. The diesel engine runs for a long time under the condition of low temperature of cooling water, and the gap between piston and cylinder liner is large. The oil temperature is too low, the oil viscosity is large, the fluidity is poor, the lubricating oil is insufficient, the lubrication becomes bad, the friction pair wear increases, and the service life of the diesel engine is shortened.
(7) In the case of low oil pressure operation
If the oil pressure is too low, the lubrication system can not carry out normal oil circulation and pressure lubrication, and the lubrication parts can not get enough oil. Therefore, the machine in the process of driving, to pay attention to the oil pressure gauge or oil pressure indicator. If the oil pressure is found to be lower than the specified pressure, it is necessary to stop immediately and continue driving after troubleshooting.
(8) Overspeed and overload of the machine
If the machine is seriously overspeed and overload, the diesel engine will run under the working condition of excessive load and high speed, which is easy to cause rough work. The heat load and mechanical load borne by cylinder liner, piston and connecting rod will increase, and the failure of cylinder drawing and tile burning is easy to occur. Often overload operation, resulting in a long time of rough combustion in the cylinder, easy to damage the cylinder pad.
(9) Slam the throttle before extinguishing
If the high-speed diesel engine stops running suddenly, its huge inertia will make the crank connecting rod mechanism and valve mechanism parts are damaged, shorten the service life. At the same time, the bang oil door is because of excessive fuel into the cylinder without enough time to fully burn and flow down the cylinder wall, diluting the lubricating oil. In addition, it will make the piston, valve and combustion chamber carbon significantly increased, resulting in nozzle blockage and piston stuck.
(10) When the temperature of diesel engine is too high, add cooling water suddenly
If cooling water is suddenly added in the case of diesel engine water shortage and overheating, the cylinder head, cylinder liner and cylinder block will crack due to the drastic change of cold and heat. Therefore, when the temperature of the diesel engine is too high, the load should be removed first, and the speed should be slightly increased. After the water temperature drops, the diesel engine will be turned off. In the water radiator cover, the steam should be removed. If necessary, cooling water can be slowly injected into the radiator.
(11) Long-term idle operation
When the diesel engine is idle, the lubricating oil pressure is low, and the cooling effect of oil injection on the top of the piston is poor, resulting in a sharp increase in wear and easy to pull the cylinder; It can also cause bad atomization, incomplete combustion, serious carbon deposition, sometimes even lead to valve and piston ring stuck, cylinder liner cavitation. Therefore, some diesel engine operating instructions clearly stipulate that the idle running time of diesel engine should not exceed 15 ~ 20min.
(1) After cold start, the machine will run with load without heating
When the cold engine of diesel engine starts, due to the large viscosity of oil and poor fluidity, the oil supply of the oil pump is insufficient, and the friction surface of the machine is poor due to the lack of oil, resulting in sharp wear, and even the failure of drawing cylinder and burning tile. Therefore, after cooling and starting, the diesel engine should run at idle speed to heat up, and then run with load when the oil temperature reaches more than 40℃; The machine should start at a low speed and drive in each gear step by step for a distance until the oil temperature is normal and the oil supply is sufficient, then it can turn to normal running.
(2) The diesel engine runs when the oil is insufficient
At this time, due to insufficient oil supply, the surface of the friction pair will be insufficient oil supply, resulting in abnormal wear or burn. For this reason, before the machine starts and the diesel engine running process to ensure that the oil is sufficient, to prevent the lack of oil caused by cylinder, burning tile failure.
(3) Stop immediately after emergency stop with load or sudden unloading of load
After diesel engine flaring out, the circulation of cooling water stops, the heat dissipation ability decreases sharply, and the heated parts lose cooling, which is easy to cause the cylinder head, cylinder liner, cylinder block and other parts to overheat, crack, or make the piston over-expansion stuck in the cylinder liner. On the other hand, when the diesel engine is shut down without idle cooling, the friction surface will contain insufficient oil, and when the diesel engine starts up again, it will aggravate the wear due to poor lubrication. Therefore, the diesel engine should be unloaded before extinguishing, and gradually reduce the speed, no load running for a few minutes.
(4) After the cold start of the diesel engine, bang the throttle
If you bang the throttle, the speed of the diesel engine increases sharply, which will cause some friction surfaces on the machine to produce dry friction and severe wear. In addition, when the piston, connecting rod and crankshaft handle force changes, causing violent impact, easy to damage parts.
(5) In the case of insufficient cooling water or cooling water, oil temperature is too high operation
The lack of cooling water will reduce the cooling effect of diesel engine, and the engine will overheat because of the lack of effective cooling. The oil temperature of cooling water and oil is too high, which will also cause the diesel engine to overheat. At this time, the cylinder head, cylinder sleeve, piston components and valves are mainly subjected to heat load, its mechanical properties such as strength, toughness and other sharp decline, increase the deformation of the parts, reduce the coordination gap between the parts, accelerate the wear of the parts, and serious cracks and stuck parts of the fault. The high temperature of cooling water and oil will accelerate the aging deterioration and burning of oil, and the viscosity of the machine oil decreases, and the condition lubrication condition of the liner and piston and the main friction pair deteriorates, resulting in abnormal wear. Diesel engine overheating will also worsen the combustion process of diesel engine, make the injector work out of order, poor atomization, carbon accumulation increase.
(6) In the cooling water and oil temperature is too low state operation
During the operation of diesel engine, the temperature of cooling water is too low, and the temperature of cylinder wall decreases accordingly. The water vapor produced by combustion condenses into water droplets, which contact with exhaust gas and generate acidic substances, which adhere to the cylinder wall and produce corrosive wear. Practice has proved that when the cooling water temperature of diesel engine is usually 40℃~50℃, the wear of its parts is several times larger than that under the normal working temperature (85℃ ~ 95℃). At this time, the temperature in the cylinder is too low when the water temperature is too low, the ignition delay period of the diesel engine is prolonged, once the fire, the pressure rises rapidly, the diesel engine fuel is rough, and it is easy to cause mechanical damage to the parts. The diesel engine runs for a long time under the condition of low temperature of cooling water, and the gap between piston and cylinder liner is large. The oil temperature is too low, the oil viscosity is large, the fluidity is poor, the lubricating oil is insufficient, the lubrication becomes bad, the friction pair wear increases, and the service life of the diesel engine is shortened.
(7) In the case of low oil pressure operation
If the oil pressure is too low, the lubrication system can not carry out normal oil circulation and pressure lubrication, and the lubrication parts can not get enough oil. Therefore, the machine in the process of driving, to pay attention to the oil pressure gauge or oil pressure indicator. If the oil pressure is found to be lower than the specified pressure, it is necessary to stop immediately and continue driving after troubleshooting.
(8) Overspeed and overload of the machine
If the machine is seriously overspeed and overload, the diesel engine will run under the working condition of excessive load and high speed, which is easy to cause rough work. The heat load and mechanical load borne by cylinder liner, piston and connecting rod will increase, and the failure of cylinder drawing and tile burning is easy to occur. Often overload operation, resulting in a long time of rough combustion in the cylinder, easy to damage the cylinder pad.
(9) Slam the throttle before extinguishing
If the high-speed diesel engine stops running suddenly, its huge inertia will make the crank connecting rod mechanism and valve mechanism parts are damaged, shorten the service life. At the same time, the bang oil door is because of excessive fuel into the cylinder without enough time to fully burn and flow down the cylinder wall, diluting the lubricating oil. In addition, it will make the piston, valve and combustion chamber carbon significantly increased, resulting in nozzle blockage and piston stuck.
(10) When the temperature of diesel engine is too high, add cooling water suddenly
If cooling water is suddenly added in the case of diesel engine water shortage and overheating, the cylinder head, cylinder liner and cylinder block will crack due to the drastic change of cold and heat. Therefore, when the temperature of the diesel engine is too high, the load should be removed first, and the speed should be slightly increased. After the water temperature drops, the diesel engine will be turned off. In the water radiator cover, the steam should be removed. If necessary, cooling water can be slowly injected into the radiator.
(11) Long-term idle operation
When the diesel engine is idle, the lubricating oil pressure is low, and the cooling effect of oil injection on the top of the piston is poor, resulting in a sharp increase in wear and easy to pull the cylinder; It can also cause bad atomization, incomplete combustion, serious carbon deposition, sometimes even lead to valve and piston ring stuck, cylinder liner cavitation. Therefore, some diesel engine operating instructions clearly stipulate that the idle running time of diesel engine should not exceed 15 ~ 20min.