AN AUTOMATIC PROCEDURE FOR THE APPLICATION OF THE ITALIAN STANDARD FOR CREEP-OPERATED PRESSURE EQUIPMENT

摘要

The Section two of the guideline [1] to the Italian technical procedure [2] concerns issues on high-temperature component assessment: it suggests, among others, the first-choice method for calculating expended life under creep conditions. One may get the time to rupture at operation temperature directly through the model chosen for the curve Larson-Miller parameter - stress. The author has written a computer program for finding the best fitting model's regression coefficients: it features the least squares analysis on points (test temperature, ultimate strength at 100000 hours) available in literature for any creep-sensitive material. A few of both the points and linear system coefficients allow providing also a simplified pocket PC program: it features the analysis for third-grade polynomial model, which may commonly fit the curve. Aim of the work is to provide both a model-functions database for most used materials in high-temperature applications and a ready-at-hand tool for life assessment.