Alstom Technology Limited

Alstom (switzerland) Ltd

General Electric Technology Gmbh

Richard Brendon Scarlin

Maurus Herzog

Herbert Bartsch

Markus Staubli

Sorin Keller

Reinhard Kn&ouml;dler

Andreas Pirscher

Reinhard Knoedler

Stefan Straub

Charles Smadja

Rodney Williams Vanstone

A method is disclosed for inspecting a weld joining a first rotor disk made of nickel alloy and having an inner surface and an outer surface concentric with the rotor's longitudinal axis to a second rotor disk having an inner surface and an outer surface concentric with the rotor's longitudinal axis. The weld made of nickel alloy fills a radial gap between the rotor disks, and has a dissimilar microstructure to either of the rotor disks. The method includes forming at least one slot in the first rotor disk extending through either the inner surface or the outer surface of the first rotor disk terminating in the first rotor disk; and passing an inspection signal from the first slot to the weld to inspect the weld for defects.

Rotor disk weld inspection method and arrangement

A welded component includes at least one high temperature segment of a high alloy Cr steel with high creep strength and a low temperature segment of a low alloy steel with high toughness and/or a high yield strength which are connected materially to one another via a weld joint. In one such component a gradual transition of chemical, physical and mechanical properties in the joining area is achieved in that between the weld joint and the high temperature segment there are at least two successive clad layers of at least two lower alloy weld metals with a total content of elements which increase the creep strength, such as for example Cr, Mo, W and V, which total content decreases toward the weld joint, and/or an increasing total content of elements which increase the toughness and/or yield strength, such as for example Ni and Mn, which total content increases toward the weld joint.

Welded component

A method for the surface treatment of ferritic/martensitic 9-12% Cr steels for the purpose of achieving an improved oxidation behavior and increased resistance to solid particle erosion at application temperatures of above 500&#xb0; C., in particular around 650&#xb0; C., in steam includes, in a first step, a known shot peening of the surface of the steel with steel particles, and, subsequently, in a second step, shot peening with glass particles, optionally, in a following third step, the surface of the steel being smoothed. A subsequent additional heat treatment is unnecessary.

Method for the surface treatment of ferritic/martensitic 9-12% Cr steel

A steam power plant with retrofit kit has a steam generator () with superheater, a steam turbine set including condensation installations (), connecting pipelines, auxiliary devices and a generator (). The steam power plant () is distinguished by the fact that the retrofit kit includes a retrofit turbine module () which is designed for elevated temperature and for unchanged or modified pressure and is connected upstream of the existing steam turbine set or is exchanged for the high-pressure turbine of the latter. Furthermore, a method for retrofitting an existing steam power plant includes the following steps: connecting a retrofit turbine module () for high operating temperatures and unchanged or modified operating pressure upstream of the existing turbine set or exchanging the existing high-pressure turbine for the retrofit turbine module (); providing a steam generator () and/or superheater () for high live steam temperature. This improves the efficiency and/or the service life of an existing steam power plant. The retention of as many original parts of the steam power plant as possible leads to an inexpensive solution for increasing output. Moreover, the general infrastructure can be maintained to the extent that to do so is economical and environmentally compatible.

Steam power plant provided with a retrofit kit and method for retrofitting a steam power plant

A thermally loaded component (), in particular a rotor for a steam or gas turbine, includes a plurality of component sections which, during operation, are exposed to different temperature levels, a first component section being designed for temperatures of &#x3e;750&#xb0; C., a second component section being designed for temperatures of approximately between 750&#xb0; C. and 600&#xb0; C., and a third component section being designed for temperatures of &#x3c;600&#xb0; C. In a component of this type, the production costs are reduced while at the same time ensuring a sufficient mechanical strength by virtue of the fact that the component () includes different materials in the component sections which are subject to different levels of thermal loading, the first component section including a precipitation-hardened nickel-base alloy, the second component section including a solution-annealed nickel-base alloy and the third component section including a high-temperature-resistant steel, and that the component () with its different component sections is constructed of individual elements () which are welded to one another and each form a component section.

Thermally loaded component, and process for producing the component

A rotor () for a thermal machine, in particular a steam or gas turbine, includes a plurality of rotor disks () which are arranged one behind the other in the rotor axis () and are welded to one another, at least one first rotor disk (), which is arranged in a section of the rotor () which is subject to particularly high thermal loads, including a nickel-base alloy which is able to withstand high temperatures and is welded to at least one second, adjacent rotor disk (), which includes a steel which is able to withstand high temperatures. In a rotor () of this type, accurate testing of the welded joints located in the high-temperature region is achieved by nondestructive testing by virtue of the fact that a first rotor ring () of a steel which is able to withstand high temperatures is inserted between the first and second rotor disks (and), which first rotor ring () on one side is welded to the second rotor disk () and on the other side is joined to the first rotor disk () via an encircling weld seam ().

Welded rotor for a thermal machine, and process for producing a rotor of this type

In a method for welding together two parts ( ), especially of a turbomachine, which are exposed to different temperatures, of which the first part ( ) consists of a steel and the second part ( ) consists of a nickel-base alloy which contains elements which are unfavorable for welding to steel, such as for example Nb, a crack-free welded joint is achieved by the fact that first of all an intermediate layer ( ), in which the amount of unfavorable elements is progressively reduced from the inside outward, is applied to the joining surface ( ) which is provided for the welding, and that then the second part ( ), which has been provided with the intermediate layer ( ), is welded to the first part ( ).

Method for welding together two parts which are exposed to different temperatures, and turbomachine produced using a method of this type

A metallic component exposed to high temperature steam is provided with a coating comprising a thin primer layer deposited on the surface of the metallic component and a thicker overlay layer on top of the primer layer. The primer layer consists of highly ductile, oxidation resistant material such that it remains free of any defects over a long period of exposure. The overlay layer consists of an oxidation resistant, less ductile, and low-cost material. It protects the thin primer layer from mechanical damage and chemical degradation. The primer layer protects the base material of the metallic component from oxidizing steam that may penetrate through cracks of the overlay layer. Due to suitable choice of coating materials and thicknesses of the layers the coating is low-cost.

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Oberflachs, Switzerland

Richard Brendon Scarlin