RED HOT SUPERHEATER COILS - DESIGN FAILURES

A CASE OF DESIGN FAILURE:

High Velocities of steam inside tubes causing less cooling of coils thus metal temperatures remain on higher side.

Higher velocity of Steam, Higher pressure drop across superheater coils & Less Flow of Steam is the culprit.

A CASE OF LOW LOAD OPERATION FAILURE:

Low velocities of steam inside tubes causing less cooling of coils thus metal temperatures remain on higher side.

Lower velocity of Steam & Low pressure drop across superheater coils & Less Flow of Steam is the culprit.

“Both High Pressure Drop & Low Pressure Drop are dangerous for Boiler’s Pressure Parts Life”. Keep a watch on Pressure drop always w.r.t. DESIGN & Allowable VELOCITIES

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