Regarding Turbine Moving Blades

Do this with Harbin:

Despite the lack of information or a photograph, I am hazarding a guess that the steam turbine you refer to is having impulse blading.

The holes provided in the discs (underneath the blades) are for equalising the pressure before and after the moving blades. In the absence of these, there is likely to be a pressure drop across the moving blade which may increase the loading on the blade to a level for which it is not designed.

GA. None such holes found on Reaction blading sections only on the Impulse sections as there should be no pressure drop across the impulse wheel only at the fixed impulse nozzles (stationary nozzle block).