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Diesel engine common parameter parsing

Diesel engine is the core component of construction machinery products, when you understand a construction machinery products, the first thing to look at is the engine parameters. However, for many newcomers joined the line and can not really understand these parameters, most of them are used and compared with the value of the product class on. In fact, for the professional master craftsman, in addition to the value on the surface, from which the above parameters can also reveal a lot of things, here we come to teach you some knowledge of engine parameters.

Diesel engine common parameter parsing

Maximum power, the rated power, the net power
Power refers to the size of the object in the work done per unit of time. Diesel engine speed is proportional to the power and, in general, the greater the power, the higher the engine speed, the mechanical efficiency and the higher the speed, the maximum power used to describe the general performance of the power machine. Therefore, maximum engine power is one of the key parameters in the purchase of construction machinery user machine. Here we come to understand the relationship between the difference between the maximum engine power, rated power, and the net power of these three between them. (Diesel engine power with rpm expressed as 180kw/2000r/min, that is, when the engine is at 2000 rpm per minute maximum output power of 180kw.)

Rated Power : Rated power is the engine does not install any accessories under actual use conditions , the maximum output power during normal operation .
Maximum power : Maximum output power is the ability to overload the engine instantly , without considering the damage, the short time to reach the peak value at this time is to test engines generally do not take transmission , air cleaner, cooling fan, etc. accessories. But some vendors in order to attract users , deliberately maximum output power and rated output power confusion , people mistakenly believe that the product has a high output power. Therefore considering the diesel engine’s power , not only the power of numbers, and marked the way to look at it .
Net power : Net power is the engine is equipped with all accessories under actual use conditions , the maximum effective power under normal operating conditions the measured engine power output shaft output . Because any construction machinery vehicles engine power when passing through filters and other accessories, the device output to the way work is absolutely the existence of consumption, the maximum available power consumption measured after what we often say that the net power .
So we come to the relationship between the maximum power , the rated power is between net power : maximum power > Rated Power > Net Power
In general, the rated power and the smaller the difference between the net power , the power structure also shows that the more rational design of this machine .
Maximum torque
Torque and power , is one of the main parameters of diesel engines , reflecting the load capacity of the diesel engine , including the lifting force , digging force , climbing ability. In the fixed power , engine torque and engine speed is inversely proportional to the size , the faster the speed the smaller the torque , the greater the contrary . ( Representation of the engine torque Nm N · m)

About Torque us give an example of popular athletes in the race when the starting moment of the outbreak of the force is the torque, so the athletes have been able to maintain power to the finish line speed. For excavators, the greater the torque greater digging force; For loaders, lifting force greater the greater the torque; bulldozer, the greater the torque thrust more robust. Under the same displacement, diesel engine torque is larger, the better the performance of this engine proved.
Number of cylinders, bore, stroke
Cylinder engine cylinders, bore and stroke determine the engine displacement, torque and power. Is the diameter of the cylinder bore, the stroke (stroke) is the distance between the bottom dead point and the ending point of the stroke of the piston, the cylinder number is the number of cylinders. Here we run down the relationship between them.

Number of cylinders under the same premise, each cylinder may be designed as a ” Big Bore × short stroke ” that can be designed as a ” small-bore × long stroke “, so it will cause a different engine engine output performance.
A ” small-bore × long stroke ” engine , because the longer piston stroke of a cylinder in the engine , and therefore the greater the power it produces , the greater the torque , but the lower the relative speed. Like a fist pull back longer than when boxing, break out when the intensity is certainly shorter than the punches efforts, but it ‘s striking speed is slower .
Conversely a ” short stroke big bore × ” engine , because it bore a large short trip, so a high speed to produce , but relatively little effort is necessary . It’s like boxing punches with small pieces can quickly hit, but the relative strength is small.
Acting cylinder number is , in the same bore and stroke , number of cylinders , the greater engine displacement , power is higher. However, the number of multi- cylinder engine of the space occupied by relatively large , apparently on small construction machinery and equipment is not applicable .
The engine is the heart of engineering machinery and equipment , in the discussion or buy construction equipment , the first thing to look at the performance parameters of the engine , so as to get better value for money device .

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