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Actions in case of Main Engine liner cracked

The engine cannot be run long in this condition. The leaking water is finding its way into the lubricating oil. The liner has to be changed.
The most logical step to take then is to isolate the faulty cylinder. It can be done.
  • Stop engine, isolate systems and allow to cool
  • Ensure a procedure is written that minimises the risk to personnel during the operation.
  • Discuss the task and written procedure with the engine room personnel to ensure they are familiar with the risks, and the methods to be used to minimise these risks.
  • Ensure the fuel pump is de-activated by lifting roller and locking.
  • Lift exhaust valve actuators so exhaust valve remains closed during running. (Note: the air spring supply to be left open)
  • Dismantle air start supply line, and blank with suitable steel plates, the main and control air pipes
  • Blank off main lube oil inlet to crosshead within the crankcase with a blanking plate.
  • Isolate the cylinder lubricator for that cylinder by placing all lubricators on no stroke.
  • Blank cooling water inlet and oulet.
The usual practice is to open up the cylinder head, remove the piston, and close back the cylinder head. All the passages that are connected to other parts of the engine will have to be blanked, so that the whole cylinder is completely isolated from the engine systems.
Since there is no piston in one of the cylinders of the engine, the crankshaft will be temporarily off-balanced. The engine has to be run at a much slower speed to avoid excessive vibration and unnecessary stress that can cause further damage.

Comments

  1. I am thankful for sharing this bulk of useful information. I found this resource utmost beneficial for me. Thanks a lot for your hard work.Waste Water Solutions Company

    ReplyDelete
  2. is it possible to repair cracked liner?

    ReplyDelete

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