Project: Material and form closure - When separating helps joining
Recognizing potential in joining systems
The growth expectations for drives, motors, and drivelines often exceed the time resources to constructively redesign all components in the area of large energy generators. The need for higher outputs and generation quantities is manifested, among other things, by damage to the weakest link in the string. In the case of electric motors that have been in operation for many years, there is very good experience of durability under the load requirements set at the time. Unfortunately, the calculation basis for evaluating the load-bearing capacity under higher performance targets is lacking here, while the redesign of existing components is subject to enormous expense.
When using unchanging system components, damage to weld seams and bolted connections occurs under increased external conditions, which does not correspond to the empirical values of the last 20 years of operation.
Existing designs of the rotor package consisting of drive shaft, adapter plates and working blades are to be examined with regard to their safety reserves. With the known prior knowledge of the damage cases under load increase, an optimum design is to be assumed at the time of design. More precisely, the causes of damage and critical elements are to be investigated with regard to optimization possibilities in order to draw conclusions on possible application scenarios.
With the verifications of the connecting elements of the bolted and welded joints, maximum transmissible performances can be defined. Furthermore, the system analysis was able to demonstrate non-critical areas of the plate connections. The transferability of the overall system can be increased if the crack positions at the weld edge are known. Thus, load application positions along the welds and to the bolted connection are specifically changed by separating cuts of the plate adaptation. Optimization and performance enhancement of existing fasteners can be achieved by utilizing previously unrecognized strength reserves of individual components.