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Classification Society Rules for STARTING AIR SYSTEM

AIR BOTTLES:- Two or more air bottles of equal capacity are to be provided. With both the bottles completely pressed up, they should be able to give 12 starts of main engine, alternately in Ahead and Astern direction, without having to replenish them with air from compressors. This is in case of reversible engines. For non reversible engines, 6 starts should be possible under similar conditions.

AIR COMPRESSORS :- Two or more main air compressors should have the capacity divided between them to fill up the air bottles starting from atmospheric pressure to required capacity within one hour.

1. Non return valve in starting air line, closest to main engine.
2. Pressure relieving device in starting air line, viz Bursting Disc.
3. Relief Valve in each Cylinder head of Main Engine.
4. Flame trap or flame arrestor in starting air line close to cylinder
5. Means to prevent admission of starting air to cylinder already          firing.
6. Fusible plug and Relief valve on air bottle.

7. Relief valve on each stage of air compressor.
8. Unloaders on air compressor.

9. Bursting disc on Inter/ after coolers.
10. High air temperature alarm for compressor.
11. Overload trip for compressor motor.


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