Chinese
1、 Starting of diesel engine
1. Preparation or backup for starting diesel engines during daily use
(1) Check that there are no impurities on the diesel engine.
(2) Check whether the valves on the lubricating oil, cooling water, fuel, and compressed air pipelines are open, and whether the power supply of the protection and monitoring system is properly connected.
(3) Check the fuel tank, oil tank, governor, and VTR turbocharger oil levels; The water level of the expansion tank should be replenished if necessary.
(4) Check the pressure of the air bottle.
(5) After shutdown or oil pressure for more than 1 hour, use the spare oil pump to pump oil to the diesel engine until the oil pressure gauge shows pressure. Open the indicator valves of each cylinder, blow off the oil and ensure that there is no oil or water spraying out of the indicator valves. If necessary, manually rotate the wheel for more than 2 revolutions.
2. Starting of diesel engine
(1) Local startup
Adjust the speed control knob of the governor to around 6 grids, place the load limit knob at the "5" mark, push the control handle to the "start" position, and the diesel engine will start immediately. After successful starting, place the control handle to the "working" position. The optimal starting speed is 200r/min, allowing the diesel engine to run at this speed for 2-3 minutes. Then adjust the load limit knob to the maximum load position, and the diesel engine can be accelerated to the calibration speed using the speed adjustment knob. Speed regulation can also be achieved through the servo motor on the speed controller.
(2) Emergency start-up
When the diesel engine fails to start the solenoid valve using the control handle or in other necessary situations, press the emergency start handle on the upper part of the main start valve. The main start valve will immediately open and the diesel engine can start. At this time, the control handle should be placed in the "working" position.
3. Maintenance of diesel engine after starting.
After starting the diesel engine, close attention should be paid to the readings of various instruments, especially the lubricating oil pressure and cooling water pressure. In any case, the lubricating oil pressure should not be lower than the specified value. At the same time, close attention should be paid to the cooling water circulation to prevent cylinder pulling caused by poor cooling water circulation. Due to the fact that compressed air is the power source for protecting system actuators, it is necessary to check the pressure inside the air cylinder after starting and replenish it if necessary. Do not close the compressed air valve when the diesel engine is running.
2、 Operation of diesel engine
1. Preheating of diesel engine
After starting the diesel engine, preheating operation should be carried out. Gradually increase the speed to 75-85% of the calibrated speed. When the outlet water temperature and lubricating oil outlet temperature reach 35-40 ℃, it is allowed to operate with a small load. The marine main engine should be preheated below 25% load (63% calibrated speed).
2. Running in of diesel engine
New diesel engines or diesel engines that have undergone replacement and repair of important components must be operated at 25% and 50% load conditions for 8-10 hours before reaching their rated power. After the first start-up, after 0.5-1 hour of operation, the vehicle should be stopped and the crankcase cover should be opened to check the condition of all moving parts, as well as whether there is any abnormal overheating phenomenon in the main bearings and connecting rod bearings.
3. Maintenance of diesel engine during operation
(1) During the operation of the diesel engine, it is necessary to pay attention to the readings and working conditions of the instruments, and keep records.
(2) The value of the oil pressure gauge should be within the specified range. If it is lower than the specified value, the vehicle should be stopped immediately for inspection and troubleshooting, and it is not allowed to continue operating. When the pressure difference before and after the lubricating oil filter is greater than 0.10MPa (1.0kgf/cm2), the filter should be cleaned. If the pressure difference suddenly changes before and after filtration, the cause should be checked and dealt with.
(3) The water pressure gauge should maintain a certain pressure and observe whether the cooling water is flowing through the flow observer (power unit layout). Observe the water outlet temperature gauge of each cylinder. Touch the temperature of each cylinder body with your hands to ensure smooth water flow in each cylinder.
(4) Check the exhaust temperature every hour, which should not exceed the specified requirements, and the temperature difference between each cylinder should be less than 30 ℃.
(5) Regularly open the indicator valves of each cylinder and check the uniformity of their operation.
(6) Pay attention to the sound of various parts of the diesel engine, and immediately check and eliminate any knocking, loose bearing knocking, or other abnormal vibrations and noises.
(7) Touch the temperature of the crankcase cover plate and the bearing area of the machine base with your hand, pay attention to the oil mist inside the crankcase, and stop the vehicle to check and eliminate any abnormal overheating.
(8) Pay attention to the confinement and locking of all exposed parts, open the observation hole cover of the cylinder head cover, and check whether the intake and exhaust valves and guide columns are flexible, whether there are any abnormalities in the lubricating oil inside the cover, whether there is water leakage, whether the bolts and nuts are loose, and whether the cylinder head is hot.
(9) Touch the compressed air pipes leading to each cylinder with your hand to check the sealing of the starting valve. If there is a leak, the pipes will heat up, and in severe cases, the vehicle should be stopped to eliminate it.
(10) Check the condition of the fuel injection system, such as whether there is severe vibration and heating in the fuel injection pump and high-pressure fuel pipe. If the fuel injector is blocked or the cylinder is overloaded, it should be eliminated immediately. Check if the fuel injection pump rack and fuel adjustment mechanism are flexible.
(11) Pay attention to the uniformity of the diesel engine speed. If there is a sudden increase in speed fluctuation, understand and identify the cause. If necessary, stop and check.
(12) Check the oil levels of the circulating lubricating oil tank, daily fuel tank, governor, and VTR booster. Add it if necessary. Identify the cause and eliminate it when the oil level changes sharply.
(13) Areas with leaks and poor sealing should be noted for prompt elimination.
(14) The air bottle should be regularly filled and maintained at sufficient pressure, and any accumulated water should be blown away. The valve of the air bottle should not be closed during operation.
3、 Parking of diesel engine
1. Normal parking
(1) Before stopping the diesel engine, remove the load from the line, then reduce the engine speed to idle and continue running for 8-10 minutes to lower the engine temperature, avoid overheating, and reduce the turbocharger speed. Then turn the control panel or joystick to the "stop" position to achieve parking.
(2) If the diesel engine is no longer started, all valves in the fuel, lubricating oil, cooling water, and compressed air piping systems should be closed.
(3) When parking for a long time in the cold season, wait for the water temperature to drop to 30-40 ℃ after parking, and drain all the accumulated water in the cooling system to prevent freezing.
(4) Eliminate any problems that may arise during the operation of the diesel engine and make all necessary preparations for starting at any time.
(5) For diesel engines that need to be stored for a long time, the original lubricating oil should be drained and sealed with sealed oil during the last parking.
2. Emergency stop
When any of the following situations occur, immediately place the control panel or joystick in the "stop" position, or press the "stop" button to stop urgently.
(1) The moving parts make abnormal noises.
(2) The bearings and other moving parts are emitting smoke.
(3) The oil pressure drops sharply.
(4) The governor, oil regulating mechanism, and fuel injection pump have malfunctioned, causing a sudden increase in diesel engine speed.
(5) The cooling water has stopped and cannot be supplied immediately. (Special attention should be paid to not rapidly supply cold water after the heat engine is shut off).
(6) The bolts of the moving parts are broken or loose.
(7) Fuel, lubricating oil, and cooling water pipes have ruptured.
(8) The coupling, gearbox, clutch, propeller, shaft system, and generator that are matched with the diesel engine have abnormalities.
(9) Other abnormal situations that can cause fatal failures in diesel engines,
Attention must be paid: When the diesel engine suddenly stops or stops quickly from a high load, the cooling water should continue to circulate in the cooling chamber for 8-10 minutes. At this time, the independently driven water pump should be started to pump water to the diesel engine.
4、 Starting and operation of the generator
The starting, excitation, and operation of the generator can be carried out according to the following steps:
1. Open the load circuit breaker.
2. Magnetic field variable resistor R1 is placed in the middle position, and when manually operated, magnetic field variable resistor R2 is placed in a position with a higher resistance value. When using automatic mode, place the excitation regulator voltage setting knob in the middle position. The single support generator should start the oil pump first to ensure smooth lubrication of the lubricating oil.
3. Start the diesel engine to slowly increase the generator speed, pay attention to any abnormal sounds at the generator bearings, inlet and outlet, AC exciter, silicon rectifier, etc., and finally stabilize the generator at rated speed.
4. Press the excitation button and quickly release it after excitation to prevent high voltage from damaging the insulation. After excitation, adjust the variable resistor R1 according to the readings of ammeter P1 and P2, or adjust the voltage setting knob of the excitation regulator when using an automatic circuit; When using a manual circuit, adjust the variable resistor R2 to stabilize the generator voltage at the rated voltage, and adjust the diesel engine speed at all times to maintain it at the rated speed. If the excitation voltage is too low and the voltage cannot be established, or if the voltage cannot be maintained at a certain value after the voltage is established, gradually reduce R1 or R2 or increase the voltage setting knob, and re excite until the voltage can be successfully established. When the no-load voltage of the generator is at the rated value and the fundamental current is roughly equal to the harmonic current, keep the positions of R1, R2 or the excitation regulator voltage setting knob unchanged, and the generator can smoothly establish voltage during subsequent excitation.
5. Close the load circuit breaker to connect the load, manually adjust the resistance value of the magnetic field variable resistor R2 and the diesel engine speed to operate the generator at rated speed and rated voltage.
5、 Shutdown of the generator
1. Gradually remove the load and adjust the generator voltage at any time.
2. When the load drops to 30%, disconnect the load circuit breaker.
3. To demagnetize the generator, turn the demagnetization switch on the control panel to demagnetize it.
4. The diesel engine slows down and stops.
5. Clean the motor and prepare for the next startup.