Sunday, 7 January 2018

AIR STARTING SYSTEM

Friends, lets know what exactly happens in AIR STARTING SYSTEM in simple way:

  1. It consists of 2 air reservoirs
  2. Reservoir used for storage of air at high pressure of 30 bar.
  3. Each reservoir has a capacity of 45 cubic meter.
  4. A stop valve is positioned next to the air reservoir.  This is manual isolation valve of the system.To prevent pressure surge this valve is opened manually.
  5. Turning gear interlock is an important interlock of any manouvering system.It prevents attempted start and admission of air to the control lines while the gear is engaged.
  6. AIR start lever in the engine room actuates pre-starting valve. It permits 30 bar to actuate the pilot valve.
  7. The pilot valve allows the passage of control air to operate automatic valve and load up distributor slide valve.
  8. The automatic valve opens and closes automatically to fill up start air manifold while starting .It conserve air during starting. often it includes  NR valve.
  9. Air distributor control valve regulates the admission of pilot air to operate cylinder air start valve in correct sequence.
  10. Cylinder air start valve admit starting air to individual cylinders.
  11. Distributor air operates this air start valve according to the firing order.
  12. An air manifold relief valve relieves excess pressure in the manifold.
  13. A flame trap prevents passage of flame from cylinder to manifold in the event of a jammed cylinder air start valve.
  14. A bursting cap ruptures to relive excess pressure in the event of start air line explosion.
  15. Pressure trips block the starting of engine if main engine and camshaft lube oil pressure are low.
Image result for Diagram of air starting system

QUESTIONS ON AIR STARTING SYSTEM:
Q1. To start a main propulsion 2s engine when the starting air is admitted into cylinder.
Ans: after TDC(affrox 15 degree).
Q2. D.E air start valve timing is controlled by ?
Ans: air start distributor
Q3. in operating condition what is the indication of leaking air starting valve?
Ans: overheating starting pipe to the cylinder head
Q4. The sequence of admitting starting air into the engine depends on?
Ans: normally the firing order
Q5. name some interlocks
Ans: turning gear interlock
        telegram interlock
         main lubricating oil pressure low interlock
          jacket water temperature high interlock
           control air pressure low

1 comment:

  1. best content on air starting system...

    ReplyDelete