Two test labs working for a seamless pipe manufacturer launched a test program to better evaluate the DCB test variability and to understand the factors of variation. The objective was to be able to give the same K ISSC values independently of the testing lab. Testing labs A and B evaluated their initial differences through inter-laboratory testing, selected the factors of variations and used an original Taguchi design of experiment approach that allowed the investigation of a quite large number of factors within a limited number of tests. Among the selected factors, variations of the arm displacement within the NACE TM0177 limits explained nearly 70% of the observed variance.
Keywords: Sulfide Stress Cracking, SSC, Double Cantilever Beam, DCB, Carbon Steel, Low Alloy Steel, NACE TM0177, Test Methodology