0

Full Content is available to subscribers

Subscribe/Learn More  >

Mechanical Behavior of Dissimilar Welds for Steam Turbine Rotors With High Application Temperature

[+] Author Affiliations
Stefan Krojer, Eberhard Roos, Andreas Klenk

Materials Testing Institute (MPA), Stuttgart, Germany

Shilun Sheng, Torsten-Ulf Kern

Siemens AG, Mülheim a.d. Ruhr, Germany

Paper No. GT2014-26738, pp. V01BT27A043; 10 pages
doi:10.1115/GT2014-26738
From:
  • ASME Turbo Expo 2014: Turbine Technical Conference and Exposition
  • Volume 1B: Marine; Microturbines, Turbochargers and Small Turbomachines; Steam Turbines
  • Düsseldorf, Germany, June 16–20, 2014
  • Conference Sponsors: International Gas Turbine Institute
  • ISBN: 978-0-7918-4558-5
  • Copyright © 2014 by Siemens Energy, Inc.

abstract

Fossil fired steam power plants of the latest generation require the elevation of steam parameters pressure and temperature to increase efficiency as well as to reduce greenhouse gas emissions. In order to achieve these goals for high temperatures, nickel base alloys could play an important role for steam turbine applications in the future. Due to technological and economical restrictions, their application in turbine rotors shall be restricted to the most heavily stressed regions. Dissimilar welds offer a known solution to combine nickel base alloys with ferritic/martensitic steels in this case.

Thermal mismatch and differences in high temperature performance of the applied base materials make it very difficult to evaluate the lifetime of such dissimilar welds. Depending on temperature and type of loading, different failure mechanisms can be observed. Further, the type of weld material plays a major role for the service behavior of the weld. Therefore, this paper describes standard creep and fatigue tests which were conducted to identify failure mechanisms and failure locations at the weld zone. To simulate the outcome of the creep tests, a modified Graham-Walles approach is used that also accounts for the different creep behavior of the heat affected zones compared to the base material. For the simulation of the fatigue tests, the model type CNOW (Chaboche-Nouailhas-Ohno-Wang) is used. The results contribute to better knowledge in designing dissimilar welds between nickel base alloys and martensitic steels under high temperature loading.

Copyright © 2014 by Siemens Energy, Inc.

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In