Abstract: A nozzle diaphragm for a turbine includes an outer ring having a groove formed along its inner surface for receiving a first locator ring, an inner web having a groove formed along its outer surface for receiving a second locator ring and partitions circumferentially spaced one from the other and connected to the outer ring and inner web. The locator rings have slots opening into the flow region for receiving tenons formed on the ends of the partitions. By precisely locating the tenons and slots, the aerodynamic characteristics of the partitions can be set during fabrication without the need for expensive and time-consuming fixtures.

Abstract: The reheat tub in a double-flow steam turbine is provided with additional setback from the rotor buckets by forming a three-part reheat tub construction including first and second discrete diaphragm segments and third inner ring segments. The annular arrays of these segments are dimensioned to enable greater axial spacing between the nozzles and buckets. To refurbish an in-service double-flow turbine, the damaged reheat tub is removed and cut along axial and radial part lines to form discrete first and second diaphragm segments. The diaphragm segment nozzles are then refurbished by adding weld material and machined to the appropriate configuration. Material is added to the downstream and removed from the upstream faces of each diaphragm so that it may be located in the turbine shell similarly as the removed tub, but with the nozzles spaced further axially upstream of the buckets.

Abstract: The reheat tub in a double-flow steam turbine is provided with additional setback from the rotor buckets by forming a three-part reheat tub construction including first and second discrete diaphragm segments and third inner ring segments. The annular arrays of these segments are dimensioned to enable greater axial spacing between the nozzles and buckets. To refurbish an in-service double-flow turbine, the damaged reheat tub is removed and cut along axial and radial part lines to form discrete first and second diaphragm segments. The diaphragm segment nozzles are then refurbished by adding weld material and machined to the appropriate configuration. Material is added to the downstream and removed from the upstream faces of each diaphragm so that it may be located in the turbine shell similarly as the removed tub, but with the nozzles spaced further axially upstream of the buckets.

Abstract: An anti-rotation device for preventing rotation of a wheel with respect to a shaft, wherein the wheel is primarily secured to the shaft by an interference shrink fit, should the interference shrink fit loosen, comprises an annular member separate from yet irrotatably secured to the periphery of the shaft, such as by an interference shrink fit, and a pair of spaced apart restraining tabs coupled to the annular member for receiving a portion of the wheel therebetween. A portion of the radial inner surface of the member may be outwardly tapered toward an axial end to assist dispersion of fluid which may accumulate in the region of the anti-rotation device. The device may include spacing protrusions for axially spacing the device from the wheel and may be disposed between a pair of wheels for preventing undesirable rotation of one or both wheels.

Abstract: A steam turbine rotor includes a plurality of turbine wheels secured to a shaft by an interference shrink fit between each wheel and a corresponding step surface on the shaft. The step surfaces have decreasing radii over a portion of the axial length of the shaft. Each wheel incudes a hub section proximate the shaft and each hub section has a shoulder portion of greater radial dimension than the radially innermost surface of the hub section. A member or finger protrudes from one shoulder and mates with a longitudinal slot on one of the step surfaces of the shaft. Relief grooves are also provided for on the shaft and hub section.