U.S. Petroleum Group Plans Bolt Fatigue Testing Program

The bolt fatigue testing program will utilize a global laboratory network in the United States and Norway. Photo courtesy of DNV GL.

The American Petroleum Institute (API) (Washington, DC, USA) awarded a contract to oil and gas industry technical advisor DNV GL (Oslo, Norway) for the full-scale stress fatigue testing of large-diameter bolts. The objective of the program is to improve fatigue assessments of bolted connections, particularly in subsea applications, by generating new test data. 

This testing will take place within the advisor’s global laboratory network involving its sites in Columbus, Ohio, USA, and Norway, which provide extensive corrosion expertise and the ability to test large capacities. These laboratories have subject matter experts in the areas of fatigue of subsea equipment, bolting connections, cathodic protection, and instrumented tests. 

“The safety of our operations is priority number one in our industry,” says Debra Phillips, vice president of API’s global industry services unit. “Our standards, technical, and certification programs are part of the many ways we help industry and companies achieve quality management and safety goals. Through research and testing such as [this work], we contribute to a culture of safety, innovation, and continuous improvement in the natural gas and oil industry.”

The program will be performed in a strictly controlled environment. The tests will be highly instrumented to record the number of cycles, stresses, strains, current, pH, and oxygen level. The testing is scheduled to be completed by late 2019.

“The type of fasteners tested are used in critical subsea applications and are often exposed to fatigue loads combined with high pressures and temperatures,” says Frank Katelaars, Americas regional manager for DNV’s oil and gas business. “Enhanced knowledge of fatigue performance will enable cost-effective designs ensuring safe operations of this critical equipment.”

The new test data will be shared on the advisor’s digital platform Veracity, which provides a secure platform for sharing key findings, test images, and all logging data with the API project team so that they can monitor tests and carry out independent analyses.

Source: DNV GL, www.dnvgl.com.