Dismantling turbocharger

Fitting up blower

Main engine turbocharger removed

Turbocharger located at the top of the photo

A turbocharger is a piece of equipment installed in diesel engines to increase the density of air for combustion so that the engine can develop more power. By using exhaust gas to drive the compressor blower, the efficiency of the engine is improved. 

Basically, the turbocharger consists of a gas turbine driven by the engine exhaust gas, which is directly coupled to a centrifugal blower. The blower draws air from the atmosphere and discharges it to the air intake manifold of the engine. Very often an air cooler cools the hot air from the compressor. The speed of rotation is high - over 10000 rpm, depending on the load at the engine.

Because of the high speed, the balancing of the shaft, and mounting of the bearings are critical. When the engine stops, the turbocharger will take some time to come to a standstill. 

The lubrication system are designed to allow for this, either in the form of self driven oil pumps, or by using header oil tanks supplying oil by gravity. 

In a marine ship environment, it is usual to allow operation up to a tilt of 15 degrees from horizontal, and a momentarily tilt of 22 degrees in heavy seas.

Overhauling of the turbocharger is a highly skilled job. Part of the job of a Marine Engineer.