1.5 COMPRESSED AIR SYSTEMS Air at high pressure, i.e. at 25 bar or more, is required for starting main 口owTR SEPARATOR and auxiliary engines in motorships Air at low pressure, say at 6 bar or less is required for much remote or temperature or pressure controlled equipment, for which purpose it must be clean and oil-free
1.5 COMPRESSED AIR SYSTEMS • Air at high pressure, i.e. at 25 bar or more, is required for starting main and auxiliary engines in motorships. • Air at low pressure, say at 6 bar or less is required for much remote or temperature or pressure controlled equipment, for which purpose it must be clean and oil-free. OIL/WATER SEPARATOR
1.5 COMPRESSED AIR SYSTEMS a typical simple h p. air system is shown in the below Figure; the arrangement of a larger system can be readily envisaged from this diagram
1.5 COMPRESSED AIR SYSTEMS • A typical simple h.p. air system is shown in the below Figure; the arrangement of a larger system can be readily envisaged from this diagram
STOP VALVES ON AIR RECEIVERS TO BE SLOW OPENING TYPE OILWATER AIR SEPARATOR RECEIVER NrV COMPRESSORS FROM EMERGENCY COMPRESSOR SDNR ALL AIR COMPRESSORS AND VALVE AUX. AIR RECEIVERS TO BE FITTED WITH DNR RECEIVER SUITABLE SAFETY VALVWS AND ENGINE VALVE AUX DRAIN VALVES ENGINE MAIN ENGINE
OIL/WATER SEPARATOR AIR COMPRESSORS FROM EMERGENCY COMPRESSOR ALL AIR COMPRESSORS AND RECEIVERS TO BE FITTED WITH SUITABLE SAFETY VALVWS AND DRAIN VALVES AUX. ENGINE SDNR VALVE SDNR VALVE AIR RECEIVER STOP VALVES ON AIR RECEIVERS TO BE SLOW OPENING TYPE MAIN ENGINE NRV AUX. ENGINE AUX.AIR RECEIVER
1.5 COMPRESSED AIR SYSTEMS AIR RECEIVER It is a requirement that there shall be at least two reservoirs whose combined capacity allows the main engines to be started twelve times if they are reversible and six times if they are not, while the e compressors are idle
1.5 COMPRESSED AIR SYSTEMS • It is a requirement that there shall be at least two reservoirs whose combined capacity allows the main engines to be started twelve times if they are reversible and six times if they are not, while the compressors are idle
1.5 COMPRESSED AIR SYSTEMS Safety valves must be fitted these may be common to the compressors but if they can be isolated from the reservoirs the latter must have fusible plugs fitted to prevent rupture in the event of fire Reservoirs are designed built and tested similarly to boiler drums Compressors are discussed, two or more independently driven are usually fitted each capable of charging one reservoir from zero to working pressures in a reasonable time
1.5 COMPRESSED AIR SYSTEMS • Safety valves must be fitted; these may be common to the compressors but if they can be isolated from the reservoirs, the latter must have fusible plugs fitted to prevent rupture in the event of fire. • Reservoirs are designed, built and tested similarly to boiler drums. • Compressors are discussed, two or more, independently driven, are usually fitted, each capable of charging one reservoir from zero to working pressures in a reasonable time