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Creep Rupture Testing of Tubular Model Components

  • R. J. Browne

Abstract

Materials data for use in design and remanent life estimates of engineering components operating in a creep regime, are invariably derived from isothermal, constant load creep and rupture tests on homogeneous specimens of simple design. In service, however, components generally operate under conditions of multiaxial stress and may be subject to systematic and random variations of temperature and load. Furthermore, the components may be of complex geometry and contain compositional and microstructural inhomogeneities introduced by welding. In theory, it should be possible to predict component life analytically using stress analysis together with materials data and an appropriate damage model. However, in practice, limitations of finite-element stress analysis in the creep range and current uncertainties in multiaxial materials data, preclude rigorous assessments for all but the more simple situations, such as a steam pipe operating under essentially constant conditions of pressure and temperature. For these reasons, laboratory creep testing of components is often desirable to underwrite their integrity in service. Currently, there are only 10 test points in the UK, at the CEGB Marchwood Engineering Laboratories (MEL), where large power plant components, such as steam pipes and headers, can be tested under conditions representative of those in service.

Keywords

Weld Metal Heat Affected Zone Hoop Stress Creep Strength Rupture Life 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Elsevier Applied Science Publishers Ltd 1986

Authors and Affiliations

  • R. J. Browne
    • 1
  1. 1.CEGB, SE Region Scientific Services DepartmentGravesend, KentUK

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