Failure Analyses

Failure analysis is the process of gathering and analyzing data to determine the root cause of a failure of a pipe or equipment. This process begins with collecting failed components for subsequent examination of the cause or causes of failure using a wide array of methods, especially microscopy and spectroscopy. The NDT or nondestructive testing methods are valuable because the failed products are unaffected by analysis. The reports in this section address failure analyses for various corrosive environments.

Select Report to read more     Failure Analysis of Stainless Steel Isobutane Piping A pinhole leak developed on the stainless steel recycle isobutane piping system at a Chemical Plant. Pitting was caused by microbiologically influenced corrosion, known in the corrosion industry as MIC. No cracks were observed in conjunction with pitting.   Read more         This report is available for download to corporate users only at this time and will be soon made available for individual purchase. Failure Analysis of a Safety Relief Valve Spring A safety relief valve failed due to corrosion fatigue. The fracture initiated at a corrosion pit and was accelerated by sulfide stress cracking and the presence of a decarburized surface layer on the spring. The H12 tool steel spring alloy is unacceptable for sourservice; it should be replaced by a material with good corrosion and H2S resistance.   Read more         This report is available for download to corporate users only at this time and will be soon made available for individual purchase. Failure Analysis of High Strength Bolts From an Undersea Tank Clamp A number of 2-inch strength bolts have failure in less than one (1) year due to corrosion fatigue. These bolts are on the clamps fastening the subsea storage tank to anchor piling. Wave action and shallow gulf sea water provided the cyclic stresses and corrosion environment. The short life of the bolts is attributed to their being insufficiently tightened.   Read more         This report is available for download to corporate users only at this time and will be soon made available for individual purchase. Failure Analysis of Production Tubing in a Gas Well The gas well under consideration with a total depth of 18,000 ft; bottom-hole temperature of approximately 350 F, while bottom-hole pressure was measured as 10,000 psi. Hydrogen sulfide content of the gas varied from 14 to 18 ppm, which is equivalent to an H2S partial pressure of 0.14 to 0.18 psia.   Read more         This report is available for download to corporate users only at this time and will be soon made available for individual purchase. Failure Analysis of 90-10 Cu-Ni Pipe The piping failed because it still had residual cold-work from fabrication, which limited its ductility during bending.   Read more         This report is available for download to corporate users only at this time and will be soon made available for individual purchase.