TURBO information

KCOC Partner Club Posts : 644 Age : 36 Location : jipun

Introduction
A turbo is a high precision 'air pump', used to supply more air into the engine by harnessing on the usually wasted energy in the engine exhaust.

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Principles of Turbocharging
The exhaust gases (dark red arrow) drive the turbine wheel and shaft, which is coupled to the compressor wheel. When the compressor wheel rotates, fresh air (dark blue arrow) is forced-fed at high pressure into the combustion chamber (light blue arrow). With a high concentration of oxygen per cubic volume and optimum air-fuel ratio, combustion is now cleaner and more complete.

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Benefit of Turbocharging
• Increases engine output and torque
• Lowers diesel fuel consumption
• Reduces harmful engine emission
• Uses more compact and lighter engines

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What is Intercooling
Intercooling is a process whereby an air cooler, called the intercooler, reduces the temperature of the compressed air intake, making it denser with a higher concentration of oxygen per cubic air volume. Coupled with turbocharging, an even higher level of combustion is achieved, thereby releasing an additional 15% engine power.

What is a wastegate
A bypass valve (wastegate/regulator) allows the turbo system to develop peak charge-air pressure for maximum engine boost response while eliminating the chance of excessive manifold pressure (overboost) at high speed. The wastegate is precisely calibrated and opens to direct some exhaust gas flow around the turbine wheel. This limits shaft speed which in turn control boost pressure.

KCOC Partner Club Posts : 644 Age : 36 Location : jipun

Kerosakan Turbine yg biasa berlaku:
TURBO information Tech_d10

Simtom dari minyak hitam..
1. Dirt In Oil

Foreign materials in oil, metal shavings, abrasives from inadequate filtration and dilution can score the bearings and destroy the oil film that supports the shaft. Dirty oil damages the turbocharger with heavy scoring of critical bearing surfaces.
Causes:
• Blocked, damaged or poor quality
oil filter.
• Dirt introduced during servicing.
• Engine wear or manufacturing
debris.
• Malfunctioning of oil filter bypass
valve.
• Poor quality oil carbonising.

TURBO information Tech_d12

2. Insufficient Lubrication

Turbocharger rotor operates at high speed on very thin film of oil. Loss of this oil film for a repetitive short duration of 4-5 sec can lead to metal-to-metal contact, wheel-to-housing rub and turbocharger failure.
Indications:
• Heat discolouration on shaft.
• Polishing and scoring on critical
surfaces such as journal/thrust
bearing.
Causes:
• Kinked/ restricted/ broken oil feed pipes.
• Low/ no oil levels.
• Oil pump failures.
• Blocked oil filters.
• Long period of non use.
• Oil contamination.
• Coked bearing housing.
• Failure to crank the engine after oil filter change.

Kerosakan akibat benda asing yg masuk dalam turbine..
TURBO information Tech_d13

Foreign object damage is caused by foreign materials entering the turbine/compressor housing and impacting the turbine or compressor wheel.
This leads to a lost of efficiency and unbalance rotation, ultimately resulting in turbo failure.
Causes:
• Foreign objects such as screws, nuts, and bolts entering the compressor
housing as a result of negligence.
• Debris from damaged air filters.
• Debris from exhaust manifold, cracked turbine housing, engine valve and
piston impacting the turbine wheel.

Extreme turbo temperatures are caused by excessive exhaust temperatures and can damage turbo during operation or shutdown.
Indications:
• Erosion of the turbine wheel.
• Cracked turbine inlet flange/wall.
• Blockage at oil drain cavity of
bearing housing.
• Deformation of turbine housing.
Causes:
• Excessive exhaust temperature due to injection pump modifications
to over deliver fuel.
• Excessive oil temperature.
• Non-approved turbine housing specifications, causing excessive
rotation speed.
• Carbonising due to poor oil quality.
• Repeated hot shutdown.