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Air Compressor requirements

  • Two starting compressors must be fitted, of sufficient total capacity to meet the engine requirements. Each compressor must be able to press up Air receiver from 15 bar to 25 bar in thirty minutes. Two air receivers must to be provided. Total air receiver capacity is to be sufficient for Twelve (12) starts of Reversible engines and six (6) starts for non-reversible engines.
  • Additional one Diesel driven or hand operated (or if possible, both) emergency air compressor must be fitted to start auxiliary engines of a “Dead Ship”.
  • Safety valves or preferably bursting discs must be fitted on the cooling water casing to give ample relief of pressure, should an air-cooling tube burst.
  • Each compressor must have a safety valve designed so that the accumulated pressure, with the outlet valve closed will not exceed 10% of the maximum working pressure.
  • The air compressor cylinders, covers, intercoolers and after-coolers, are tested by hydraulic pressure to twice their working pressure.
  • The casing of the inter-cooler and after-cooler is hydraulically tested to 1.5 times cooling water pressure. Thus, for 4 bar cooling water pressure, the casing will be tested at 6 bar pressure.
  • A water separator or drain should be fitted on the airside of each intercooler. The drain cock should be used at regular intervals to prevent water from one stage being carried into the following stage.
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