New Standards for Quality Control and Assurance of Bolted Flanges

If necessity is the mother of invention, then the American Society of Mechanical Engineers (ASME), the Occupational Safety and Health Administration (OSHA), and the Environmental Protection Agency (EPA) are the parents of guidelines, standards, and regulations that help keep industrial operations safe for humans and the environment. While the great majority of global business managers are already seriously committed to conducting safe practices to avoid mishaps and reduce risk in their construction and operational activities, the adoption of standards and guidelines can assist mangers when hiring and training their personnel, staying within regulatory compliance, and documenting safety procedures. To support such endeavors, ASME periodically publishes new series of guidelines and standards — some of which are specifically for bolted flange and joint assemblies.

Historically, the management of bolted flanges has been regulated by relatively limited guidelines. However, recent events have illustrated the need for new standards. In fact, in 2013, the Environmental Protection Agency reported that 32% of all volatile carbon emissions came from bolted flanges. For example, several years ago an offshore platform in the North Sea experienced a large and costly fire. The investigation showed that a carbon steel ring had been inserted between two stainless steel flanges through a weak positive material verification program and passed the helium pressure test. Three years later the carbon steel ring eroded away from galvanic corrosion and leaked. Eventually, the process release was enough to cause a fire that spread across the platform and upon investigation, inspectors determined that the incident occurred, in part, due to a lack of standards and procedures for bolted joints, although a plethora of standards exist to govern welded joints. In fact, according to ASME, practically no requirements for bolted joints existed, compared to welded joints, even though bolted joints hold back the same process conditions and therefore pose a similar risk. As a result, industry managers are encouraged to treat bolted joints with the same attention to detail and safety as a welded joint (see Figure 1) and evaluate the training and competency of bolting technicians much the same as coded welders.