The solution of certain problems of freight transport is determined by the developed capacity. The KamAZ turbocharger allows you to increase the working capacity of the car, remaining one of the most effective ways, despite the efforts of scientists and designers in promoting potentially new ideas. Consider the characteristics and features of this device.
The standard operation of a diesel engine involves the formation of a fuel-air mixture in the combustion chamber from the volume of air that "under its own power" enters when the piston is lowered. In this case, the fuel does not completely burn out, while potential energy is lost, and the power unit does not develop the power it is capable of. The KamAZ turbocharger allows you to forcibly increase the amount of air entering the combustion chamber. This is the simplest, but also the most effective solution to the problem.
The unit in question is pressurized. As a result, the fuel-air composition burns better, as a result of oxygen saturation. If we consider in more detail how the process is “better”,it must be understood that a unit amount of fuel gives off more energy, which increases the power of the engine. As practice shows, the KamAZ-5490 turbocharger gives an increase in power up to 40%. It is noteworthy that the increase in power rating does not require structural changes to the engine.
More active and dense combustion of fuel significantly reduces the emission of toxic exhaust gases. The amount of smoke is also reduced due to the reduction of residual solid products (soot). Simply put, the overall environmental safety of the motor is increased.
Installing a turbocharger on KamAZ increases fuel consumption. But, in general, fuel costs for obtaining a unit of power in such an engine are lower than in a conventional counterpart. That is, the supercharged “engine” is “gluttonous”, but also more powerful. As a result, the use of a power unit with a turbine to obtain a specific power is more profitable than achieving the same indicator on a conventional diesel engine. Below is a diagram of a gas turbine pressurization.
1 – heat exchanger; 2 - radiator of the cooling system; 3 – fan; 4 - motor; 5 and 6 are turbochargers.
KAMAZ turbochargers have a simple design. In fact, two elements interact in this device (a centrifugal compressor and a gas turbine). The first component part consists of these parts
- skeleton in the form of a snail;
- wheels with blades of a specific configuration;
- holes through which air enters, flowingthrough a diffuser into the engine intake manifold.
A gas turbine has a similar structure, only instead of air, exhaust gases are fed into it, which are discharged into the exhaust system.
The wheels of both elements are connected by a central body, and the torque is transmitted through a roller. Therefore, the energy for the operation of the unit is produced from the exhaust gases.
1 - bearing; 2 - screen part; 3 - body; 4 - diffuser; 5 – sealing ring; 6 - nut; 7 - oil reflector; 8 – compressor wheel; 9 – screen of oil discharge; 10 - damper; 11 - skeleton of bearings; 12 - fasteners; 13 - adapter; 14 - gasket; 15 – turbine screen; 16 - wheel; 17 - body; 18 - seal.
In the KAMAZ (Euro-1/2/3/4) turbocharger, the exhaust gases are fed into the turbine, interact with the wheel blades, transferring their own kinetic potential to it, spinning it up to 75 thousand rotations per minute. The turbine element transforms the torque into a compressor analog, which takes in atmospheric air, actively throwing it against the walls and accelerating it to high speed. Further, the mass enters the tapering diffuser part, where it is compressed, being supplied under pressure to the intake manifold, then to the combustion chambers.
Because the turbine functions stably under high pressure and mechanical stress, its body is made of special reinforced alloys. Good bearing lubrication is required to ensure high wheel speeds.This condition is ensured by oil lines that are connected to the engine lubrication system.
It is worth clarifying that KamAZ trucks are equipped with two-row V-shaped engines. For them, it is appropriate to use a pair of turbine compressors (one element for each row). It is more economical to use two small models than one large unit. The turbines of the considered devices have relatively small dimensions:
- impeller diameters - no more than 61 mm;
- similar turbine and compressor dimensions - 220mm;
- the mass of one element in the assembly is about 7 kg.
The use of such compact units makes it possible to dramatically increase the motor parameter.
Types and classes
There are four categories of engines that comply with environmental standards on the modern market. Depending on these parameters, the type and brand of the compressor is selected. This information is shown in the table below.
KAMAZ 740.10 and 7403
KAMAZ 740.11 and 740.13
TKR7, K27, CZ, Schwitzer
KAMAZ trucks 740.31-240/740.51-320/740.30-260/740.50-360
All of the above brands upgraded to Euro 2
KAMAZ trucks 740.37-400/740.63-400/740.60-360/740.62-280/740.61-320
Models K27-TI and Swiss Schwitzer S2B
KAMAZ turbocharger (Euro 4) is mounted on some truck modifications. It interacts so far only with the Cummins engine, differs in design and parameters from domestic counterparts.
The devices in question are produced by a limited number of manufacturers. Among them:
- Joint-stock company KamAZ manufactures standard affordable versions for its engines. In the range of modification "Euro 0-2".
- Association "Turbotechnika" (located in the Moscow region, Protvino). The company specializes in the production of TKR KAMAZ turbochargers of various models.
- Company "Turboengineering". Offers versions of K27-TI, standards from "Euro 1" to "Euro 3".
- The BZA Society, located in Belarus, offers analogues to units of the TKR7 type.
- Czech factory in Strakonice. High-quality copies of K-27 are made here, the price of which is slightly higher than domestic products.
- The German concern Borg Warner Turbo systems sells high-quality turbine compressors under the Schwitzer brand.
For KamAZ, all units are presented in the right or left version. This is important to consider when purchasing the product, as mounting on the opposite row is not possible.
Because thethe device is under significant stress, it is not surprising that sooner or later it breaks. Common faults include:
- Insufficient oil supply. Running dry bearings lead to shaft displacement, which is fraught with wheel deformations and complete failure of the entire unit.
- Ingress of foreign objects into the structure. In this case, a small piece or shavings from the valve or piston will be enough for the rotor to jam. Most often, such a malfunction occurs due to a violation of the operating rules. Even hitting a piece of cloth or rubber causes the blades of the element to bend.
- Deformation and wear of the KamAZ turbocharger gasket. In this case, the defective element must be replaced.
Most often, the cause of failure is a lack of oil. This may occur even after the engine has stopped.
There are other reasons why turbine compressors fail. In most cases, the problem is solved radically - by purchasing a new model. Although the repair will be cheaper, the rebuilt unit will not last long, which will require additional costs.
Repairing the device is complicated by the fact that the part is subjected to significant loads. Therefore, jeweler's precision is required in the processing and installation of spare parts. This requires special equipment and tools. Experts recommend purchasing a new unit, since their price is affordable. The repair of only expensive analogues is partially justified.
The following are recommendations for installing a KAMAZ turbocharger (Euro 2):
- Change the oil, air filter and oil filter first.
- It is necessary to ensure that all plugs are removed from the unit.
- Thoroughly clean all incoming and outgoing piping.
- Install a new gasket.
- Follow the tightening torque recommended by the manufacturer's documentation.
- After starting the engine, check the mechanism for leaks, before loading, let the engine idle for a few minutes.
In their responses, the owners point to the simplicity of the design and replacement of the KamAZ turbine compressor. The specified unit is available in various types, which makes it possible to choose the necessary model, depending on the type of motor. The disadvantages include the poor maintainability of domestic modifications, but the low price levels this disadvantage.