WÄRTSILÄ WARTSILA 20, Product Manual

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8.2 External compressed air system
The design of the starting air system is partly determined by classification regulations. Most
classification societies require that the total capacity is divided into two equally sized starting
air receivers and starting air compressors. The requirements concerning multiple engine
installations can be subject to special consideration by the classification society.
The starting air pipes should always be slightly inclined and equipped with manual or automatic
draining at the lowest points.
Fig 8-2 External starting air system (DAAE007204F)
System components
Compressor (Starting air compressor unit) 3P01 Air filter (Starting air inlet) 3F02
Separator (Starting air compressor unit) 3S01 Starting air compressor unit 3N02
Starting air vessel 3T01 Air dryer unit 3N06
Size Pipe connections
OD28 Staring air inlet 301
OD6 Instrument air inlet 320
8.2.1 Starting air compressor unit (3N02)
At least two starting air compressors must be installed. It is recommended that the compressors
are capable of filling the starting air vessel from minimum (1.8 MPa) to maximum pressure in
15...30 minutes. For exact determination of the minimum capacity, the rules of the classification
societies must be followed.
8.2.2 Oil and water separator (3S01)
An oil and water separator should always be installed in the pipe between the compressor
and the air vessel. Depending on the operation conditions of the installation, an oil and water
separator may be needed in the pipe between the air vessel and the engine.
8.2.3 Starting air vessel (3T01)
The starting air vessels should be dimensioned for a nominal pressure of 3 MPa.
Wärtsilä 20 Product Guide - a13 - 6 September 2016 8-3
8. Compressed Air System Wärtsilä 20 Product Guide