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Cooling system
The cooling system serves to maintain optimal tion of the thermal regime of engine is controlled from- water heat from the most heat stressed parts in the result Tata of contact with hot gases or friction. Overheating of the engine decreases its power, increases fuel consumption. Excessive overheating DWI gates causes of burning grease, with sharply rising melting wear of the rubbing surfaces of the parts. Happen bullies and melting of the bearing shells, the destr- of the surface of crankshaft journals, jamming then tied. In addition, the gasoline engine can who- to nicoti detonating punches. Out the engine down. On the other hand, an overcooling of the engine is also not- preferably. Increased losses of engine power to overcome the increased friction due to more dense smaz- CI. The fuel mixture, condenses, washes away the film of oil from the cylinder walls and increases wear of the piston howl of the group. Increases corrosion of mirrors cylinders resulting in the formation of sulfuric and sulfurous connections. And, as a result, there is deterioration of the top tidal efficiency and a significant reduction of the period service of the engine. In automotive engines often use liquid STN and less air cooling system. When the air cooling system transmission heat from the engine going directly into the atmosphere ru. The required intensity of the cooling is achieved the cooling fins of the cylinders and their heads, the fan and the deflector. The system is easy to operate, has a small mass and warms up the engine after starting. However, the air cooling system is there significant disadvantages: poor uniformity of heat extraction the height of the cylinder, big loss of engine power on fan drive, the noise operation. In automotive engines the most often used the liquid cooling system with forced CIR- kulala fluid. As the coolant at- change water or an antifreeze fluid — entire- PS, the aqueous solution ethylenglycole ("Antifreeze"). The flow of the circulating fluid is directed into the first turn to the most heated parts of the engine: the walls combustion chamber, spark plugs, exhaust valves, the cylinders of the engine. The heat from the heating parts is transmitted through the wall of the engine accessories cooling fluid, and from it also through the outer walls of the units the cooling system into the atmosphere. The liquid cooling system include: • cavity (shirt) cooling the block and head qi lindros; • radiator with shutters. • fan; • water pump (pump); • the thermostat; • temperature sensor coolant; • water distribution pipe; • pipes and hoses with the fixing parts; • surge (expansion) tank; • drain taps; • the heater of the driver's cab (cabin); • the pre-heater. Coolant circulates in the cavity (Rubach- ke) of the block and cylinder heads, cylinder liners washing and the walls of the combustion chamber. Then, washing flushing valve- new, cool them and is supplied to the cavity of the heated intake- tion of the collector. Next, through the upper nozzle cooled- based liquid enters the top tank of the radiator, where Oh- razdaetsya by the air flow flowing through the tubes in the lower- tion radiator tank, through the pipe and the hose goes to water pump. The water pump ensures enforcer- ing the circulation of the coolant. He is from the crankshaft drive belt. The intensity of cooling fluid is regulated by the Ter- moschatum, which depending on the temperature of the liquid let it STI for a large or small contour cooled p- tion, and also disable and enable the fan. Refilled the system with coolant through the filler neck of the expansion tank. Merges the liquid from the system through drain valve and faucets of preference additional equipment of the car. Liquid cooling system in modern cars- carts — closed type, i.e. it communicates with the at- the atmosphere through the vapor valve raising the boiling point of the liquid and reduces its evaporation. Compared with an air cooling system liquid the skeletal system is better regulated, more evenly cool gives engine parts, uses far less power- ti to drive water pump and fan, noiseless in work. However, this system is expensive and vulnerable to air operation. The liquid cooling system is also used for cooling of compressor air brake system. Radiator is designed to cool the liquid bones, the receding heat from the engine parts. Cooled p- tion of fluids takes place in the core of the radiator, typed- Noah from copper, brass or aluminum tubing on which has cooling fins, made of La tuni or steel. The core connects the upper tions and lower tanks of the radiator. The stream of air blown the core of the radiator is controlled by the position of the flaps blinds, as well as in modern models of cars from- the connection and switching of the fan via temperature- sensor coolant. Fuel filler neck the upper radiator tank closed tube with provosts- tion valve. When overheating of the coolant and the increase in vapour pressure of the liquid is higher than rated the valve automatically opens. Expansion tank is connected by a pipe with the upper the radiator tank and is designed to compensate for the betrayal of the amount of low-freezing coolant (" Sol") when the engine is running and after it stops. Tube the tank has a vapor valve. Blinds are designed to control the airflow for- lit by a counter flow of air. Many blinds are made from- sensible plates. To manage their situation from Kabi NY driver has a drive. Water pump - centrifugal type provide no forced circulation of liquid in cooling system- Denia. The pump is installed in the front of the block qi lindros and consists of a helical silumin yr- sa, a shaft with impeller and self-sealing gland. Rotating impeller creates a centrifugal force, under the action of which the fluid from the center of the pump housing from- bracelets towards the outer walls. Leakage of fluid connector between pump housing and engine block prevents the rubber gasket, and the shaft — samolot- nausica the seal, consisting of rubber seal, steel Noah clips and a textolite thrust washer. The fan provides airflow of the fan and of the engine by increasing the flow of air through the core of the radiator. The fan has several lopas- TEI, made of steel or plastic with a special form to reduce the cost of its drive. For improve the airflow to the engine can be mounted on the RA- ditore guide casing. |
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