8. TURBOCHARGER 8.1.3 Structural and functional outline 8.1.4 Components (1) Turbine The exhaust gas from the engine is accelerated at the nozzle portion in the turbine housing and blown onto the turbine impeller to rotate the turbine shaft. This is called the turbine. A seal ring and heat insulating plate are installed to prevent the bearing from adverse influence of the gas. (2) Compressor The compressor impeller installed on the turbine shaft rotates with the shaft to suck and compress air for feeding into the intake manifold. This is called the blower or compressor.
(3) Bearings Thrust bearing As the turbine shaft is constantly applied with a thrust force, this bearing prevents the shaft from being moved by the thrust force. Radial bearing A floating bearing is adopted. Since the bearing moves with the turbine shaft as the oil films are formed both inside and outside the bearing, the bearing sliding speed is slower than the turbine shaft speed, result- ing in higher dynamic stability. (4) Compressor side sealing mechanism To prevent the intake air and oil from leaking, a seal ring and a seal plate are provided to form a double wall structure on the rear side of the compressor impeller.
(5) Waste gate When the blower side pressure (intake air pressure) exceeds the specified level, the exhaust gas at the tur- bine inlet is partially bypassed to the exhaust discharge side to control the turbine rpm so as to maintain the intake pressure at the specified level for improving the response to load variation in the low to medium speed range and to minimize black smoke generation. It consists of a control assembly separated from the turbocharger and a valve assembly installed in the turbine impeller chamber. 82E-5 – 98E-5 SERIES 8-3 No. Part name No.
Part name 1 Turbine shaft 11 Turbine housing 2 Oil thrower 12 M6 hexagon bolt 3 Turbine side seal ring 13 Turbine side clamp 4 Seal plate 14 Lock washer 5 Journal bearing 15 Bearing housing 6 Thrust bearing 16 Retaining ring 7 Compressor housing 17 M3 countersunk flat head screw 8 M5 hexagon bolt 18 Compressor wheel 9 M5 spring washer 19 Shaft end nut 10 Compressor side clamp 20 Heat protector