Hot corrosion and cold corrosion.

Hot corrosion
           It is basically vandium corrosion. Vanadium is present in fuel oil,when vandium and sodium is present in a ratio of 1:3 vanadium pentoxide a hard component is formed whose melting point is 630°. Due to high temperature in combustion chamber these melts into metal surface and leaving the surface exposed to corrosion is called as hot corrosion.
Cold corrosion

  •          Cold corrosion occur due to presence of sulphuric acid inside liner surface. This abnormal corrosion can cause wear and tear inside liner. This occurs due to new regulations that engine should be operated at high pressure and low temperature. This temperature below due point will result in deposit of water droplets inside liner surfaces and this water combine with sulphur in fuel to form sulphuric acid.

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