General Electric Company

Todd Joseph Fischer

John Francis Nolan

Dennis William Roberts

David Roy Parker

Ralph Arnold Pollock

John Matthew Sassatelli

Andrew John Tomko

Carter Cook

John Francis VanNest

David Ward Marcellus, Jr

Jeffrey Philip Fregoe

Bin Wei

Ralph James Carl, Jr

Martin Kin-Fei Lee

Andrew J Travaly

David John Grubish

Vladimir Pilic

Nick Scott

Kevin Brian DeWan

N Kutty Nair

Jason Stroosnyder

Roy Cleveland Parker

Edward James Oziminski

Chris Kilburn

Carter Steven Cook

Bucket tip tenons requiring refurbishment are removed from the bucket tips by grinding. Groups of buckets are clamped on a rotatable table in positions adjacent an induction heating coil and a robotic welding arm, respectively. While one group is preheated, the other group of buckets is in a welding location, enabling the welding head on the robotic arm to sequentially apply weld buildup material to the bucket tips. After applying weld buildup material in multiple passes and sequentially to the bucket tips, the buckets are removed, stress-relieved and the weld buildup material machined to provide refurbished tenons. Upon removal of the buckets from the table, the table is rotated to locate the preheated buckets in welding locations and additional buckets are clamped to the table for preheating.

Apparatus and methods for repairing tenons on turbine buckets

A machining apparatus is provided. The machining apparatus includes a discharge machining head assembly and a slide assembly supporting the head assembly. The machining apparatus also includes an electromagnet configured to support the slide assembly in a position on a work piece to machine an area. The slide assembly permits linear displacement of the head assembly generally parallel to the supporting work piece surface.

Apparatus and method for machining in confined spaces

A method and apparatus for cleaning a generator or turbine component using a laser ablation technique. The method includes programming a controller coupled to a laser source for controlling the laser source to perform laser ablation. A laser beam is directed at a generator or turbine component surface for vaporizing surface contaminants and coatings deposited on the generator or turbine component surface without changing material properties of said generator or turbine component. A computer system having a processor and a database is communicatively coupled to the controller. The database is loaded with turbine or generator component data and corresponding laser power related data for ablating surface contaminants and coatings from respective components. The apparatus also includes a detector disposed adjacent to the turbine or generator component to monitor ablation process and provide feedback data to the computer system, and a comparator for comparing the feedback data with predetermined data to determine progress of ablation. The laser source is controlled to produce a laser beam depending on the comparison step.

Method and apparatus for cleaning generator and turbine components

Using sinker electrode discharge machining tools, damaged portions of partitions of the turbine which have been removed and replaced with weld material of increased thickness may be shaped and contoured to blend with the suction and pressure sides of the partitions. The diaphragm containing the partitions is located in a tank containing dielectric material. A numerically controlled EDM machine directs first and second sinker EDM tools having surfaces corresponding to designed surfaces of the trailing edge portions of the partitions applied to contour and shape the opposite surfaces of the weld material to blend with the pressure and suction sides of the partitions. A third EDM tool is used to shape the juncture at opposite ends of each partition with the arcuate surfaces of the inner and outer bands.

Method or repairing trailing edge portions of partitions in turbine diaphragms

The broach assembly includes alternate spacers and cutters arranged in a sub-assembly having a lead at a leading end and a lag at a trailing end. The cutters have side margins in excess of the margins of the spacers for cutting material from the dovetail slots of the turbine wheel as the broach assembly passes through the slots. The bottom or apices of each spacer and cutter are tapered to form a continuously tapered surface along the bottom of the broach assembly. Upon passing the broach assembly through the slot, the assembly is progressively displaced in a radial outward direction to progressively cut the active dovetail slot surfaces. Shims may be disposed in the bottom of the slot to further displace the broach assembly radially outwardly in multiple passes.

Multi-part dovetail repair broach assembly and methods of use

A broach assembly includes an elongated base having a central upward projection and a pair of side flanges and a tapered undersurface. Releasably mounted on the projection are multiple tool holders spaced along the length of the base. The tool holders mount cutters for engaging active surfaces of the wedge slot as the broach assembly is passed through the wedge slot. Shims may be interposed between the tool holders and base to increase the elevation of the cutting surfaces relative to the undersurface of the base to progressively increase the bearing pressure of the cutting surfaces against the active surfaces of the slot during multiple passes of the broach assembly through the wedge slot.

Apparatus and methods for refurbishing generator field wedge form slots

An automatic machine for peening the tenons on bucket cover plates to secure the cover plates and adjacent buckets of a turbine wheel to one another is provided. The machine includes a fixture having stepped surfaces for locating the freely suspended fixture and peening tool relative to the bucket tips and cover plates and clamping the tips and cover plates to the fixture surfaces. After peening a first tenon, the fixture and tool head are displaced relative to the fixed cover plate and bucket tip to register the tool with a second tenon. An actuator displaces the suspended system to compensate for the movement of the fixture and tool relative to the turbine wheel. A counterbalance is provided to accommodate fixtures of different weights when peening the tenons of covers in different turbine wheels.

Apparatus for automated peening of tenons connecting turbine buckets and cover plates

The broach assembly includes alternate spacers and cutters arranged in a sub-assembly having a lead at a leading end and a lag at a trailing end. The cutters have side margins in excess of the margins of the spacers for cutting material from the dovetail slots of the turbine wheel as the broach assembly passes through the slots. The bottom or apices of each spacer is tapered and extends beyond the corresponding surface of the cutter to progressively displace the assembly in a radial outward direction to progressively cut the active dovetail slot surfaces. Shims may be disposed in the bottom of the slot to further displace the broach assembly radially outwardly in multiple passes.

Methods for automated peening of tenons connecting turbine buckets and cover plates

A method of removing a pin from a hole including a) drilling a first hole of a first diameter in the pin a selected fraction of a length dimension of the pin and attempting removal of the pin; b) if the pin cannot be removed, drilling a second hole of a second diameter smaller than the first diameter an extended fraction of the length dimension of the pin; and c) removing the pin.

Method of drilling dovetail pins

A method has been developed for removing turbine buckets that have become stuck to a turbine rotor wheel. This method includes making two or more first cuts to the base of a female dovetail of the turbine bucket. Two or more second cuts are also made to a lower neck of the female dovetail. The blade of the bucket is broken off at the first cut, which breakage also splits the base of the dovetail into two sections. These sections are pressed down along the second cuts so that they may be removed from the wheel.

Method for removal of dovetailed turbine bucket from a turbine wheel

A method of brazing a plurality of copper strands to a buss bar includes: a) cleaning the buss bar and the copper strands; b) positioning a filler shim on the surface of the buss bar; c) placing a copper strand on the filler shim, the filler shim and the strand having substantially equal lengths; d) stacking additional copper strands on the buss bar, with a filler shim between each adjacent pair of strands; and e) heating the filler shims utilizing an induction brazing coil to a temperature sufficient to cause melting of the shims and to thereby form a brazed lap joint between the copper strands and the buss bar.

Growing community of inventors

Ballston Spa, NY, United States of America

Todd Joseph Fischer