STEAM TURBINE  BLADES

TURBINE  BLADES :

The efficiency of the turbine depends more than anything else on the design of the turbine blades the impulse blade must be designed to convert the kinetic energy of the steam into mechanical energy the same goes for the reaction blades which furniture some must convert that heat energy to kinetic energy. The later years increase in blade efficiency is due to increased aerodynamic shape calculated by computers and the milling of blades an automatic milling machines.

It is not always possible to give the blades the theoretically best profile as  several other considerations must be taken the blade must be made strong enough to withstand high temperatures and stress from heavy often pulsating steam load  there is also the stress due to centrifugal force for large LP blades the centrifugal force a single blade may exceed zoo tones vibrations and resonant vibrations, in particular, must be taken into account and finally there is erosion and corrosion.

The material that comes closest to the ideal all motioned considerations is a chromium-nickel steel for instance 17cr 13Ni – steel.