Introduction Mechanical integrity is one of the most important barriers between normal refinery operation and a major accident. In simple terms, mechanical integrity is the assurance that pressure equipment, piping, tanks, heaters, valves, flanges, small-bore connections and associated components are suitable for their intended service and remain fit for continued operation. It is not just about inspection. It is not …
Credit: CSB On April 3, 2017, a catastrophic failure occurred at the Loy-Lange Box Company in St. Louis. A pressure vessel—the Semi-Closed Receiver (SCR), which stores hot condensate at 100 psig—violently ruptured. Propelled like a missile, it tore through the facility, launched through the roof at 120 mph, and crashed into a neighbouring building 520 feet away, killing four people …
Residual stresses are an often-overlooked but critical factor in the long-term reliability and safety of pressure equipment such as vessels, piping, and storage tanks. These stresses, which remain within a material after fabrication processes like welding, forming, or heat treatment, can significantly influence equipment’s structural integrity under high-pressure and high-temperature conditions. In this article, we explore residual stresses, where they …
Pitting corrosion poses a serious threat to the integrity of metallic structures, primarily due to its highly localised nature. Unlike uniform corrosion, which affects larger areas more predictably, pitting targets small, concentrated spots on a metal’s surface, leading to the formation of cavities or “pits” that can penetrate deeply into the material. Even when the overall mass loss is minimal, …
FITNESS FOR SERVICE ASSESSMENTS (FFSAs) UNDERSTANDING THE FOLIAS FACTOR We like to keep things simple on our FFS training courses at Wilkinson Coutts. In FFS codes, the term shells describes pipes, vessels, and tanks collectively. The FOLIAS factor (M) is a critical component in assessing these shells. So, what is it? It’s just a stress concentration factor to acknowledge …