While the offshore oil and gas industry has made substantial progress in improving subsea bolts’ reliability, multiple opportunities exist for it and the US Bureau of Safety and Environmental Enforcement to work together and establish a forum to do more, a committee at the National Academies of Science, Engineering, and Medicine concluded in a new report.
The study’s objective was to identify actions that could reduce the probability of a fastener failure that unintentionally could release oil, gas, or drilling fluids into the ocean. It focused on bolts, nuts, studs, and fasteners used in critical connections.
“There is a keen interest in improving the reliability of offshore equipment and structures, and in reducing the risk of damage to the environment to as close to zero as possible,” the report by a committee on connector reliability for offshore oil and gas operations assembled at BSEE’s request noted.
“With many disparate views on the preferred approach, there must be a forum by which everyone has an opportunity to contribute their ideas and have them adequately investigated to enhance the development of offshore resources,” it said.
Bolt manufacturers must keep track of more than 1,000 specifications that address various aspects of high quality design and manufacturing, the report said. Multiple changes to specifications and standards are often made in response to bolt failures or technology changes, and the result has been a multitude of proprietary standards which do not foster cooperation and shared expertise across the industry, it said.
Standards, by themselves, will not solve offshore oil and gas fastener reliability issues, it added. An industry research and development program will be required to provide much-needed data and analysis, it said.
The report said that BSEE and the offshore oil and gas industry could work together to provide a roadmap which could:
• Investigate bolting cluster failures using a large-scale, fully instrumented test rig that simulates undersea conditions on fasteners.
• Research and develop innovations that could notably advance the reliability of critical fasteners in offshore service.
• Identify gaps in current standards and obtain the necessary data to provide updates.
• Promote a strategic vision for the safety culture throughout the oil and gas industry.
It also recommended that the offshore oil and gas industry establish a standard laboratory test method to assess how susceptible bolting materials are to cracking and embrittlement from exposure to hydrogen; review the standards such as those related to bolt tensioning, in order to minimize the likelihood of excessive stress being placed on bolts in subsea environments; and promote an enhanced safety culture across organizations and disciplines that is reflected in work rules and encourages all levels of the organization to improve undersea bolts’ reliability.
