Abstract: A rotor cooling circuit includes a cooling medium supply reservoir for supplying cooling medium to a plurality of axial passages through the turbine wheel and spacer disc rims. A passageway communicates cooling medium from the reservoir for flow in series and in a serpentine manner in and about the cavities between the wheels and discs. The flows are reunited at a plenum for flowing the cooling medium into first and second stage buckets. Return passages through the rims of the wheels and spacer discs return spent cooling medium from the buckets to a return location external of the rotor. Transition elements between the buckets and spacer plates in the rotor rim accommodate any thermal mismatch between the adjoining buckets and spacer plates to prevent cooling medium leakage at the joints.

Abstract: Particulates are removed from the coolant used to cool gas turbines by subjecting the coolant to the centrifugal acceleration of the gas turbine rotor. Axially oriented channels are formed in the rotor at a radial distance from its longitudinal axis. The channels are in fluid communication with a coolant supply passage so that coolant coming onboard the rotor will first pass through the channels. The high centrifugal force produced by rotor rotation causes particulates in the coolant passing through the channel to move radially outward and deposit on a fixed surface in the channel. Thus, the particulates are collected in the channel and removed from the coolant discharged from the channel. The channels may be provided with removable liners.

Abstract: The steam transfer arrangement includes dovetail connections between a turbine bucket 14 and rotor wheel 12 wherein a steam supply passage 20 in the rotor wheel registers with a steam return passageway 28 in the bucket and a steam return passageway 30 in the bucket lies in registry with a steam return passage in the wheel. At the interface of the dovetail connection, each registering passage and passageway includes a sleeve 50, 52 disposed in an enlarged recess 54, 56, the sleeves having annular spherical sealing surfaces for engagement with annular spherical seats on the turbine bucket. The sleeves are compressible radially relative to the bucket to enable the bucket to be secured to the wheel and expand radially outwardly to ensure sealing fit between the sealing surfaces and seats.

Abstract: Large turbomachines such as steam turbines and gas turbines will have an operational lifetime which may be measured in terms of decades. During the operational lifetimes it is desirable to monitor the condition of major parts of the turbomachine such as rotors and rotor wheels. Procedures are available for non-destructive testing of major turbomachine parts but it is desirable to affirm the actual condition of a turbomachine rotor by a sacrificial test of a speciment taken from a forging from which the actual turbomachine part was made. Further, it is desirable that the specimen be in service with the turbomachine part so as to obtain an accurate operating experience. To this end, a specimen taken from a turbomachine forging is affixed to a finished turbomachine part and then run with the machine for latter removal and test.

Abstract: A transition portion adjacent the uncored section at a trailing edge of a cored turbine bucket displaces some of the regions of maximum stress concentration so that the maxima do not superpose and produce radial cracking at the junction of the uncored section with the walls of the cored portion. The transition section includes a curved portion joining a ramp leading to the tip.

Abstract: A dovetail of a rotor blade is preferentially remove to thereby modify the support given to the root of a rotor blade. The modified support changes the vibrational characteristics of the rotor blade for reducing the tendency toward crack initiation. In one embodiment of the invention, one or more damping masses are fitted into the dovetail slot within the removed portion of the dovetail. The damping masses are loaded outward against the base of the rotor blade by centrifugal force and frictionally damp some of the vibrational energy of the rotor blade.

Abstract: Dovetail spacers containing slots enable final balancing of a turbine or compressor rotor or wheel without employing grooves or drilling holes in the wheel itself. The spacers are installed in the normal fashion and, when final balancing is performed, appropriate weights are inserted into the slots in selected ones of the spacers. Fine tuning can be performed by drilling or grinding the weights. In one embodiment, the spacer is provided with a radial hole which joins an axial hole. After the turbine or compressor rotor is assembled, additional counterweight material can be added through the radial hole and then be held in place by suitable means such as a setscrew. In this embodiment, weights of suitable material can also be removed as necessary.

Abstract: An improved windage nut for fastening components of a gas turbine rotor assembly is disclosed. The outer portion of the nut has two lateral extensions for meeting with similarly shaped nuts adjacent to said nut to prevent rotation of the nut, and in combination with a plurality of similarly shaped nuts forms a ring shaped member having a smooth outer surface whereby friction and stresses are reduced during rotation of the rotor.