What are the main maintenance components of a diesel engine?

Maintenance 1: Fill the inside of the bearing of the fresh water pump with grease.

Maintenance standard: replace the waste grease inside the water pump bearing, and the amount of new grease added should be 1 2 2 3 of the bearing chamber volume.

Equipment: Grease gun, grease and wiping cloth.

Maintenance method: First fill the inside of the grease gun with grease, and then fill the grease nozzle of the fresh water pump.

Technical requirements: When filling grease, it is necessary to align the grease nozzle to prevent grease from overflowing and causing unnecessary waste.

Maintenance content 2: Fill the inside of the generator bearing with lithium grease.

Maintenance standard: replace the discarded ZL-3 lithium grease in the generator bearing, and the number of new lithium grease should be 1 2 2 3 of the bearing chamber volume.

Equipment: ZL-3 lithium grease, grease gun and screwdriver.

Maintenance method: First, fill the inside of the grease gun with ZL-3 lithium grease, and then fill the grease nozzle on the outside of the generator bearing. For engines that do not have grease nipples, the bearing cover can be removed and lithium grease can be inserted.

Technical requirements: When filling grease, it is necessary to align the grease nozzle to prevent grease from overflowing and causing unnecessary waste.

Moving parts: including piston rings, pistons, cylinder liners, as well as oil pumps and grease nipples.

Oil filters, diesel filters, valves.

Fuel injection pump and exhaust gas turbocharger.

1. Machine body and crankcase.

Second, the timing gear room.

3. Cylinder head.

Fourth, gear train.

5. Crankshaft. 6. Pistons.

7. Connecting rods. 8. Camshaft.

9. Oil cooler.

10. Pressure limiting valve for main oil channel.

Ten. 1. Oil pump.

Ten. 2. Fuel injection pump.

Ten. 3. Injector assembly.

Ten. Fourth, air filter.

Ten. 5. Turbocharger.

The main components of the diesel engine generally include: the body, the crank connecting rod mechanism, the valve mechanism, the fuel system, the lubrication system, the cooling system, and the electrical system.

1. Body: It is the skeleton of the diesel engine.

2. Crank connecting rod mechanism: it is the main moving part of the diesel engine.

3. Valve mechanism: It is to open and close the intake and exhaust valves regularly.

4. Fuel supply system: according to the needs of the diesel engine, the diesel fuel is supplied to the combustion chamber for combustion at regular and quantitative intervals.

5. Lubrication system: supply lubricating oil to each moving friction pair.

6. Cooling system: It dissipates the heat generated by the diesel engine when it is working to the atmosphere.

7. Electrical system: it is auxiliary equipment for starting, lighting, monitoring and operation.

Yizhong Power Station Diesel Generator Set) diesel engine is the diesel engine used in the diesel generator set is the power output part, it uses diesel as fuel, and relies on the high temperature and high pressure air formed after compression in the cylinder to make the sprayed mist diesel combustion and expand and do work, and convert heat energy into mechanical energy. Because diesel fuel is ignited by compressed high-temperature air, diesel engines are also known as compression-ignited internal combustion engines. The diesel engine used in the diesel generator set is generally a four-stroke water-cooled high-speed diesel engine.

The so-called four-stroke diesel engine is a diesel engine that completes a working cycle in the four processes of air intake, compression, work (expansion) and exhaust.

There are many types of visual inspection machines, and the classification methods are also various, which can be divided into single-cylinder and multi-cylinder diesel engines according to the structure of the body, among which the multi-cylinder diesel engine is divided into in-line type and V-shaped arrangement type according to the different cylinder arrangement methods; According to the air intake mode, it is divided into spontaneous combustion suction type and pressurized type; According to the working cycle process, it is divided into two-stroke and four-stroke; According to the cooling method, it is divided into air-cooled and water-cooled; According to the use, it can be divided into power generation, marine, vehicle, agricultural irrigation, construction machinery and other industrial supporting diesel engines; According to the rated speed, it is divided into high speed (rated speed in more than 1000r min), medium speed (rated speed in the range of 600 1000r min) and low speed (rated speed in less than 600r min), the rated speed of the diesel engine used in the diesel generator set is generally 1500r min or 3000r min.

There are many models of generator sets in use, and the power is different, among which most of the medium and large generator sets are fueled by diesel, and the generator sets with smaller power are generally fueled by gasoline.

The diesel generator set with the diesel engine as the generator power source has several advantages compared with the gasoline generator set with the gasoline engine as the generator power source:

1. Fuel economy. The thermal efficiency of the diesel engine is high, the fuel consumption rate is low, and the fuel water pump rate curve changes relatively flat when the working conditions change, which is very important for the diesel engine that often works under partial load.

2. Reliable and durable. Since the diesel engine does not have an ignition system, there are relatively few failures and high working reliability.

3. Wide range of use.

4. Less harmful emissions.

5. Good fire safety.

The low-pressure oil circuit mainly includes the fuel tank, fuel filter and low-pressure oil pipeline.

Summary of high and low pressure oil circuits of traditional machines: low-pressure oil circuits include: fuel tank - fuel filter hail cleaner - low-pressure fuel pipeline - hand oil pump - oil return pipe.

The low-pressure oil circuit includes: mailbox - fuel filter - low-pressure oil pipeline - low-pressure oil pump low-pressure stage - oil return pipe.

The high-pressure oil circuit includes: high-pressure fuel injection pump (including flow metering valve) - high-pressure pressure accumulator (including track, including rail pressure sensor) - high-pressure oil pipe - injector assembly.

The professional and technical knowledge of on-site diagnosis, on-site maintenance and emergency treatment of common faults of diesel engine, and the maintenance technology of key parts of diesel engine are explained. The main contents include: comprehensive and practical technology of diesel engine repairer key service, common fault diagnosis and maintenance on the way, common fault diagnosis and maintenance of lubrication system, fault diagnosis and maintenance of abnormal temperature, common fault diagnosis and maintenance of fuel system, common fault diagnosis and maintenance of valve mechanism, common fault diagnosis and maintenance of crank connecting rod mechanism, common fault diagnosis and maintenance of supercharging system, key points of maintenance of electronically controlled diesel engine fuel system, emergency treatment technology of fault during operation, etc.

This book can help maintenance service personnel and operators in the diesel engine industry to understand and master the knowledge of diesel engine fault diagnosis and maintenance, and can also be used as a reference for teachers and students of relevant majors in colleges and universities.

The diesel engine is composed of the engine body, two major mechanisms (crank connecting rod mechanism, air distribution mechanism), and four major systems (fuel supply system, lubrication system, cooling system, and starting system).

The body is the frame of the diesel engine, which is composed of the cylinder block and the crankcase, and the crank connecting rod mechanism is composed of the piston connecting rod group, the crankshaft flywheel group and other parts. The valve train is composed of a valve group, a valve transmission group, and a valve actuation group.

The fuel supply system includes a fuel supply device, an air supply device, a mixture gas formation device and an exhaust gas exhaust device. The lubrication system consists of an oil supply device and a filtration device. The cooling system includes radiators, water pumps, fans, etc.

The starting system includes a starting motor or a starting internal combustion engine and a transmission mechanism.

Diesel tanks, fuel pumps, low-pressure oil pipes, diesel filters, fuel injection pumps, high-pressure oil pipes, fuel injectors, oil return pipes, etc. Main circuit: fuel tank--- low-pressure pump--- high-pressure pump--- injector.

Diesel engine fuel supply system.

Storage of diesel fuel in the diesel tank.

Fuel pump zhi

Ensure that the diesel is circulated in the low-pressure oil circuit

ring, and return a sufficient amount of fuel and a certain pressure to the fuel injection pump, and its fuel delivery volume should be 3-4 times the maximum fuel injection volume of the full load.

Low-pressure tubing. Deliver diesel.

Diesel filter.

The function of the diesel filter is to filter out harmful impurities and moisture in the fuel system, protect the normal operation of the engine, reduce wear, avoid clogging, and improve the life of the engine.

According to the load of the diesel engine, the fuel injection pump will increase a certain amount of diesel fuel to a certain pressure and send it to the injector at the specified time.

High-pressure tubing. Deliver diesel.

The injector atomizes the diesel into fine particles and distributes the oil mist reasonably.

Excess fuel in the return line flows back to the fuel tank through the return pipe.

The diesel engine oil supply system consists of a diesel DU tank, an oil pump, a low-pressure oil pipe, and a diesel filter

Fuel injection pump, DAO high-pressure oil pipe, fuel injector and oil return pipe are composed. The diesel fuel is sucked out from the diesel tank by the fuel pump, and a certain pressure is generated, and the impurities are filtered out by the diesel filter and then enters the fuel injection pump, and the fuel injection pump increases the oil pressure of the low-pressure oil, and the high-pressure oil is sprayed into the combustion chamber through the high-pressure oil pipe and the injector. Due to the large amount of fuel supplied by the fuel pump, part of the excess diesel oil flows back to the fuel pump or diesel tank through the injector return pipe, and the other part flows back to the diesel tank through the pressure limiting valve and the return pipe.

Diesel Engine Fuel System:

First of all, there must be a fuel tank for diesel oil, and secondly, there must be a fuel injector device that injects high-pressure diesel into the cylinder of the diesel engine. In the past, each cylinder of the diesel engine corresponded to a high-pressure oil pump, and the high-pressure fuel produced by the high-pressure oil pump was sprayed into the cylinder through the fuel injector through mechanical transmission when the cylinder needed fuel, and the high-pressure oil pump corresponding to each cylinder was integrated together and loaded into the same shell, which was called the high-pressure oil pump assembly. Now the oil rail type is mostly used, that is, a pump device that produces high-pressure oil will pump the diesel fuel into the oil rail, which cylinder needs high-pressure oil, and the injector (oil valve) is driven by the computer control device, so that the high-pressure oil in the oil rail is injected into the cylinder.

Of course, there are also supporting diesel filters, diesel pipes, low-pressure oil pumps and so on.

Low-pressure oil circuit, oil pipeline, oil-water separator, coarse filtration, hand oil pump, diesel fine filter, fuel injection pump, high-pressure oil pipe, fuel injector, oil return pipe.

Low-pressure oil circuit (fuel tank - oil pipeline - oil-water separator - coarse filter - hand oil pump - diesel fine filtration) - high-pressure oil circuit (fuel injection pump [solenoid valve] - high-pressure oil pipe - fuel injector) - oil return pipe - fuel tank.

Fuel tanks, primary filters, fuel transfer pumps, filters, fuel injection pumps, fuel injectors, combustion chambers.

The roles of these three parts are:

Sensor: real-time detection of diesel engine, vehicle operation status and the user's operation idea - operation volume and other information, and send to the controller. The basic sensors are: engine speed sensor, shank displacement sensor, fuel injection advance angle sensor and accelerator pedal position sensor.

Controller: Its core part is the computer, which is responsible for processing all the information, executing the program, and outputting the results of the operation to the actuator as control instructions. In addition, there is a communication function, that is, with other control systems - such as transmission controller for data transmission and exchange, while considering the real-time situation of other systems, appropriate correction of the fuel system execution instructions, that is, appropriate correction of fuel injection amount, injection advance angle, etc.

At the same time, the necessary information can be sent to other control systems.

Actuator: According to the execution instructions sent by the controller, the corresponding mechanism is driven to adjust the amount of fuel injection and the timing of fuel injection, so as to adjust the operating state of the diesel engine. In the in-line pump system, there are governor actuators that adjust the displacement of the shank of the fuel injection pump, advance actuators that adjust the phase difference between the engine drive shaft and the fuel injection pump camshaft, thereby adjusting the fuel injection time, and there are also some unique actuators in the distribution pump system.