engleski

Accuracy Test at Low Speed Operation of the "Georg" Machining and Balancing Centre

In production od stream turbine rotors, but often during overhaul as well, new blades are inserted. After the blade insertion operation, the rotor has to be machined and the tips of the blades with no shrouds have to be ground. During the turbin rotor overhaul the bearing journals have to be turned and ground as well. The rotor that was originally balanced and overspeed tested in an overspeed vacuum tunnel can be successfully balanced at lower speed after the new blades of last stages have been replaced. Performing these operations on stationary lathe and balancing machine would be too expensive due to necessary modifications of machine fixtures and high cost of rotor transportation from the plant to the workshop. Furthermore, last stages of the low-pressure turbine rotor have large blade diameters. Design of the special lathe for such a span would not pay off. The problem is solved with a portable machining centre for tuning, grinding and balancing. Apart from these operations, the centre is capable of blade insertion as well.

balansing accuracy; balansing speed; residual unbalance. permissible error

nije evidentirano