1. Diesel engine
Diesel engine is an engine that uses diesel as fuel. At present, the most commonly used diesel engines in rural areas are single-cylinder, horizontal, water-cooled four-stroke diesel engines. We have already understood the structure and working principle of diesel engines in physics. This section only briefly introduces the correct use, maintenance, and simple fault analysis and troubleshooting methods of diesel engines.
The correct use of diesel engine
1. Diesel engine running-in: a new or overhauled diesel engine must be run-in to work at full load before it is officially used. Otherwise, it will accelerate the wear of parts and make the diesel engine unable to exert the maximum effective power and shorten the service life of the machine. , The running-in of the diesel engine is divided into three stages:
(1) Dry running: Run the diesel engine at low speed for half an hour, then stop it to check for abnormalities and bolt tightening. Then run at medium speed for 2 hours, and finally run at rated speed for 30 minutes. If there is any abnormality, stop and make adjustments in time.
(2) Light load run-in: run at 1/3 load for 10 hours, then run at 1/2 load for 23 hours, and finally run at 2/3 load for 10 hours.
(3) Running at full load for 10 hours, the total running-in time is about 50 hours. Before starting to run-in, check the connection of each part of the diesel engine, whether enough diesel, engine oil, and cooling water are added as required, and observe whether there is oil leakage, water leakage, or leakage. The phenomenon of qi. Rotate the machine with the crank to check the oil supply. During the running-in process, pay attention to the sound of the machine and observe whether the oil pressure and water temperature are normal. After the running-in is completed, release the oil while it is hot, clean the oil pan, crankcase, and oil filter, and replace with new oil. Check whether the main bolts are loose, check the valve clearance, and readjust if necessary.
2. Diesel engine maintenance: After the diesel engine has been working for a period of time, the parts are worn out. Loose connections and other reasons have gradually deteriorated the technical status of each department. If serious maintenance is not carried out on time, a long time will cause power drop, fuel consumption increase, abnormal sound, and even serious accidents. In order to prolong the service life of the diesel engine and make it work in good technical condition, it is necessary to do a good job of technical maintenance work carefully, not just use it without maintenance, or even make the machine work with illness. Technical maintenance includes regular maintenance and regular maintenance. Regular maintenance is to clean the exterior, check the fastening of connecting rod parts, the technical status of other parts, lubricate the lubrication points, add enough oil and water. Regular maintenance is carried out after a certain working time. Generally divided into maintenance No. 1, 3, 4. The maintenance of No. 1 higher than the maintenance includes all the contents of No. 1 lower maintenance, but also add cleaning, lubrication, tightening and adjustment items. If necessary, replace the expired or expired The maintenance period of the damaged parts is calculated based on actual working hours, and some calculated based on the actual oil volume of the diesel engine. In actual work, it should be strictly implemented in accordance with the requirements in the manual.
3. Winter use of diesel engine: The temperature in winter is very low, it is easy to block the oil circuit of the diesel engine, the cooling water is frozen, and it is not easy to start. Therefore, the following issues should be paid attention to when using diesel engines in winter:
(1) Use special winter oil, and preheat the oil before adding it to the machine before driving. When preheating the engine oil, it is not allowed to burn it directly with a strong fire. Instead, place the barrel of engine oil in water and use fire to heat the water and indirectly heat the engine oil.
(2) Use diesel for winter to prevent the diesel from being mixed with moisture and causing the diesel to freeze.
(3) To prevent the cooling water from freezing after parking, the cooling water should be discharged when the water temperature drops to 40°C.
4. Safe use of diesel engine: Safe use of diesel engine can ensure that people are not injured and the machine can work normally.
(1) It is strictly forbidden to operate by people who do not understand or are not familiar with the diesel engine. When working, they must concentrate their energy, clear out possible accidents at any time, and cannot leave the job without authorization.
(2) It is strictly forbidden to use unqualified diesel, engine oil, and cooling water, and keep the diesel, engine oil, and cooling water clean.
(3) When the diesel engine is working, the exposed transmission belts, gears, and transmission shafts should be protected to avoid personal injury.
(4) Before starting, clean up other tools and remind the people present before starting.
(5) When the diesel engine is working, it is necessary to always pay attention to whether it is running well, and it is not allowed to overload the machine for a long time. Lubrication, adjustment, and maintenance work are not allowed during machine work.
(6) The work site must have complete and effective fire protection equipment.
2. Common faults and troubleshooting methods of diesel engines
Insufficient pressure in the cylinder and difficulty in starting the main symptoms are: burning oil, blue smoke from the exhaust, increased oil consumption, a large amount of smoke-like gas discharged from the crankcase vent, and the horsepower of the diesel engine decreased. The main reasons are:
1. The cylinder liner, piston ring, and piston are worn out, and air leaks during the compression stroke. Insufficient compression force in the cylinder makes it difficult to start. Individual parts or complete parts should be replaced.
2. The piston ring is stuck in the ring groove due to carbon deposits and glue. Most of them are caused by incomplete diesel combustion, burning of engine oil, and poor quality of engine oil. The carbon deposits on the cylinders, pistons, and piston rings can be removed in time, and qualified engine oil and diesel can be selected.
3. The opening of the piston ring is in a straight line. This may be an installation error, or the piston ring may automatically shift due to the wear of the cylinder liner. The piston rings should be reinstalled so that the openings of the rings are staggered.
4. If the valve is not closed tightly, the valve clearance should be readjusted, the valve and valve seat should be replaced, or grinding should be carried out.