HomeCalculatorsShaft Alignment - Cold-to-Hot Sag

Shaft Alignment - Cold-to-Hot Sag

Cold-to-hot shaft-alignment compensation - thermal growth ME + jacket water heating compensates geometry.

Shaft alignmentSagEngine
Engine thermal rise
1.44mm
Formula, assumptions, and limits

Steel α = 12e-6 /K. ME rises 0.5-1.5 mm hot. Cold alignment targets give offset (typically +0.3-0.5 mm below nominal). Shaft bearings loaded correctly hot.

Symbol legend

SymbolMeaningUnitSource
Steel thermal expansion/Ksteel properties