This procedure aims to achieve a satisfactory rotor balancing. In general, the steam turbine rotors are not balanced with incremental balancing, as it would be required on API612. In Nuovo Pignone standard the rotor shall be balanced fully assembled, including turning gear wheel, speed detecting bush and when applicable turning gear connection. In case of customer request, after the rotor balancing completion, the rotor can be checked also with the coupling hub assembled on. Only when the overspeed is performed without high speed balancing, if the turning gear wheel and the speed detecting wheel interfere with the equipments of the bunker, it is allowed to perform the test without these components effecting their assembly and a balancing check in a following phase (see also ITN07203.01). In case of wheel to drive pump or turning gear to be climbed on the rotor in following phase, they must be drawn to assure the correct assembly and they shall have separated balancing plane suitable also to balance at field.