Centrifugal bunker

Centrifugal bunkers are used in turbine and generator production to test the finished products for stability during rotation before delivery . A spin bunker has meter thick concrete walls to the kinetic energy record from falling turbine blades or cracked shafts in the case of material failure.

Large generators and turbines in power plants have to be able to handle enormous speeds (nominal speed 1500 or 3000 min ⁻¹ ). At these speeds, generator shafts or turbines have such a high kinetic energy that material failure would endanger people and buildings over a large area. In the case of turbines, the blades are particularly at risk. Should these become detached from the shaft, the entire machine hall of a power plant can be destroyed. The same applies to the rotors of generators. These are particularly at risk if the braking electrical load from the public power grid breaks away due to a line fault and the quick-closing valves of the turbine do not close in time (risk of a generator running away in the event of uncontrollable centrifugal forces). The opposite is the case with a short circuit close to the generator (“full short circuit”), which leads to abrupt braking of the shaft (risk of bursting due to uncontrollable braking forces). Turbines and generators are therefore brought to critical speeds in a centrifugal bunker before they are delivered and commissioned. The centrifugation in the centrifugal bunker thus represents the most important quality test of generators and turbines and thus ensures the perfect operation of these machines in power plants. A centrifugal bunker exists z. B. on the Siemens factory premises in Mülheim (generator and turbine production).