Device and method for rotational speed increasing for machining process

A spindle assembly configured to be assembled at an internal taper socket of a tool holder, the assembly having a rear end and a front end, the front end being proximal to a tool clamping system of the assembly, and the rear end being proximal to an end of the assembly opposite to the tool clamping system, the assembly comprising:

• a rotating shaft configured for rotation within the tool holder;
• a bearing assembly, comprising a front end bearing assembly and rear end bearing assembly, configured to support the rotating shaft within the tool holder and to enable rotation of the shaft within the tool holder;
• a turbine operatively connected with the rotating shaft, the turbine configured to rotate the rotating shaft;
• a hollow housing to mechanically support the components of the spindle assembly;
• and
• a plurality of slots formed in the outer surface of the housing and configured to form, with the inner surface of the taper socket of the tool holder, passages to allow high pressure coolant fluid, of 8-90 Bar, to flow from the tool holder to drive the turbine,
• wherein at least one bearing of the bearing assembly is disposed in a part of the spindle assembly which is configured to be situated in a space defined by the taper socket of the tool holder and a front clamping nut.