Estimation of Creep Deformation in Components From Short-Term Proof Test Data

The paper describes a technique for estimating creep deformation from the results of short-term proof tests. The method relies on the concept of a reference stress which is representative of the general stress level in the component. It is shown that the method provides an upper, and therefore safe, bound on creep deformation. Application to a complex piping component is used to illustrate the procedure and some of the practical problems of interpreting the experimental data. Finally, an attempt is made to relate the reference stress method to tentative design procedures in Code Case N.47 of the ASME III Code.