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Diesel Generator sets
Diesel engine and parts
Diesel Engine Classification Introduction
April 14, 2022
Diesel engine is a machine that uses diesel fuel as fuel, burns and releases heat in the cylinder, and directly uses the expansion of gas to generate pressure to push the piston to do external work. It is widely used and plays an increasingly important role in daily life. There are many classification methods of diesel engines. Today, JUNVOCH will come to tell you about it.
1. Classification by cooling method
1) Water-cooled diesel engine, which is a diesel engine that uses water as a cooling medium to cool parts such as cylinders and cylinder heads. There is a water jacket around the cylinder of the diesel engine, and water is used to cool the cylinder. Water-cooled diesel engines have different treatment methods for cooling water, which can be divided into two types: cooling water open circulation and cooling water closed circulation. Diesel generator plants commonly use water-cooled diesel generator sets.
2) Air-cooled diesel engine, which is a diesel engine that uses air as a cooling medium to cool parts such as cylinders and cylinder heads. There are many fins around the cylinder of a diesel engine, which use the flow of outside air to cool the cylinder. Emergency backup power supply or mobile power supply (power car) multi-purpose air-cooled diesel generator set.
2. Classification by air intake
1) Suction diesel engine refers to the diesel engine in which the air entering the cylinder is not compressed by the compressor, that is, the diesel engine directly inhales the surrounding air to operate. For a four-stroke engine, it is also called a naturally aspirated diesel engine.
2) A supercharged diesel engine refers to a diesel engine in which the air before entering the cylinder has been compressed by a supercharger. After the diesel engine is supercharged, the unit volume power of the cylinder can be increased, but for the diesel engine with a high speed (10,000 to tens of thousands of r/min) of exhaust gas turbocharger, the service life is short.
3. Classification by fuel supply method
1) Direct injection diesel engine, which is a diesel engine that injects fuel directly into an open or semi-open combustion chamber.
2) Indirect injection diesel engine, which is a diesel engine that injects fuel into the sub-chamber of the separate combustion chamber.
4. According to the different classification of high and low speed
1) Low-speed diesel engines generally refer to diesel engines with crankshaft speed n≤500r/min, or average piston speed Vm<6m/s.
2) Medium-speed diesel engine generally refers to a diesel engine with a crankshaft speed of 500/min<n<1000r/min, or an average piston speed of Vm=6~9m/s.
3) High-speed diesel engines generally refer to diesel engines with crankshaft speed n>1000r/mim or average piston speed Vm>9m/s.
Low-speed diesel engines are mainly used as marine main engines, and their low-speed performance is good. Diesel generator sets generally use medium and high-speed diesel engines. The higher the speed of the diesel engine, the smaller the volume, the lighter the weight per unit of power, and the faster the wear and tear. The unit is small in size and occupies a small area. Therefore, high-speed diesel engines should be preferred for standby power stations and emergency power stations.
5. Classification by work cycle
1) Two-stroke diesel engine refers to a diesel engine in which the piston completes one working cycle through two strokes (360° of crankshaft rotation). The two-stroke diesel engine is characterized by a large output power per unit cylinder volume. At present, domestic diesel generator sets are rarely used.
2) A four-stroke diesel engine refers to a diesel engine in which the piston completes one working cycle through four strokes (the crankshaft rotates 720°).
At present, most domestic diesel engines adopt the four-stroke working mode.
6. Classification according to the number of cylinders
1) Single-cylinder diesel engine refers to a diesel engine with only one cylinder.
2) Multi-cylinder diesel engine refers to a diesel engine with more than two cylinders.
7. Classification by cylinder arrangement
1) Vertical diesel engine refers to a diesel engine in which the cylinder is arranged above the crankshaft and the centerline is perpendicular to the horizontal plane.
2) Horizontal diesel engine refers to the diesel engine with the cylinder center line parallel to the horizontal plane. The arrangement of diesel engine cylinders includes horizontal, star and H-shaped arrangements. At present, only horizontal single-cylinder diesel engines are used for agricultural machinery such as walking tractors in these forms, and other forms are rarely used.
3) In-line diesel engine refers to a diesel engine with two or more vertical cylinders arranged in a row. The cylinders of the diesel engine are arranged vertically in a single row, which is called a single row diesel engine. This form is commonly used in diesel engines below 6 cylinders.
4) V-shaped diesel engine refers to a diesel engine with two or two rows of cylinders, the angle between the center lines of the cylinders is V-shaped, and the output power of a common crankshaft is shared. The cylinders of the diesel engine are arranged in a V-shaped oblique double row, which is called a double-row V-shaped diesel engine. Diesel engines with more than 8 cylinders often use this form.
8. Classification by usage
1) Marine diesel engine.
2) Diesel engines for agricultural machinery.
3) Diesel engine for tractor.
4) Diesel engine for power generation.
5) Diesel engines for locomotives.
6) Diesel engines for automobiles.
7) Diesel engines for tanks.
8) Diesel engines for armored vehicles.
9) Diesel engines for construction machinery.
10) Diesel engines for aircraft.
11) Diesel engines for motorcycles.
12) Diesel engines for small machinery, such as lawn mowers, electric welding units, powerful water pumps, etc.
9. Classification by control method
1) Manual diesel engine means that the operation of the diesel engine adopts local manual operation.
2) Automatic diesel engine means that the operation of the diesel engine can be carried out automatically or in a compartment.
10. Classification by starting method
1) Manual start diesel engine refers to a small diesel engine started manually.
2) Electric starting diesel engine uses the starting battery to make the starter motor run to drive the diesel engine to start.
3) Assist the gasoline engine to start the diesel engine, first start the small gasoline engine by manpower, and then start the diesel engine by the gasoline engine.
4) Air-starting the diesel engine is to use compressed air to pass through the cylinder to push the piston to start the diesel engine.
11. Classification by power size
1) Low-power diesel engine, generally refers to diesel engine below 200kW.
2) Medium power diesel engine, generally refers to 200~1000kW diesel engine.
3) High-power diesel engine, generally refers to the diesel engine above 1000kW.
The above are the types of diesel engines that JUNVOCH has sorted out for you according to different characteristics. No matter how the diesel engines are classified, they are all to meet the needs of convenience. When purchasing a diesel engine, users should pay attention to check whether the diesel engine has a beautiful appearance, neat appearance, and whether there are scratches on the surface. Or deformed, incomplete, etc., whether there is a product standard code mark implemented by the product on the product certificate or instruction manual.
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