Abstract: The turbine includes inner and outer rings and partitions mechanically connected therebetween. In one form, the partitions have connecting elements at tip and root portions of the vanes which are received in complementary grooves in the outer and inner rings, respectively. The partitions in one form are stacked against one another and secured by end lugs at the diaphragm joints. In another form, the partitions are pinned to the outer and inner rings with spaces between the connecting elements to avoid accumulation of tolerances. In a third form, the partitions are applied against the outer and inner rings in an axial direction and retainer plates are bolted to the outer and inner rings to secure the partitions in the diaphragm assembly. In all cases, the diaphragm is formed without welding.

Abstract: A method and apparatus is disclosed for determining whether certain rotor stress values are exceeded during the thermal cycle of a turbomachine. The invention takes into account the rotor material and the behavioral characteristics of the rotor material above and below the Fracture Appearance Transition Temperature (FATT). The acquired data is stored to develop a rotor history useful in determining a rotor condition for maintenance and longevity purposes and further useful in determining the operating pattern of the turbomachine.

Abstract: The useful life of a turbomachine part is affected by cyclic stresses which occur in the turbomachine part as a result of heating and cooling the turbomachine part. Each thermal cycle is comprised of a maximum heating stress and a maximum cooling stress which may occur during turbomachine start-up, load changes, shut-downs, or boiler excursions. The maximum heating stress and the maximum cooling stress for each cycle may be combined to define a stress range. The actual stress range for each cycle is compared with a calculated stress range curve for the turbomachine part to determine the amount of life expended during the cycle for the turbomachine part. This value may be expressed as a percent of life expended for the cycle. The life expended for each cycle is accumulated to provide an output indicative of the total percent life expended for the turbomachine part according to its operating history.