Inadvertent Valve Disassembly Results in Loss of Containment

Litigation, North America

When an operator couldn't open a valve, he tried to get better access to open it with his wrench. In the process, he mistakenly removed bolts from the valve body, resulting in a gas release, explosion and fire. Baker & O'Brien was engaged to investigate the incident cause. We provided expert opinions in the areas of process equipment design, process safety management, risk management, competence management and human factors.

During reinstatement of equipment following a refinery process unit turnaround, a pump suction valve had to be opened for flow alignment. When the valve handwheel freely turned and failed to open the valve, the operator decided to remove the gearbox so he could manually turn the valve stem with a wrench.

However, the operator mistakenly removed the valve top cap bolts instead of the gearbox bracket bolts, which resulted in a loss of containment, explosion, and fire.

A few personnel present in the vicinity at the time of the release were injured from the explosion and fire and filed a claim for their injuries. Baker & O'Brien was engaged to investigate a number of relevant issues: 1) the incident cause; 2) applicable plug valve standards; 3) gearbox bracket mounting and design changes; 4) operator training and competence; 5) industry practices for operator maintenance; 6) human factors and the error type; 7) potentially related incidents and OSHA notices; and 8) the likelihood of an incorrect gearbox removal. We provided expert opinions and rebuttals in the following areas of expertise: operations, maintenance, process equipment design, process safety management, competence management, risk management, incident investigation, and human factors.

Melvin M. Sinquefield

Senior Consultant

Petroleum Refining
Standard of Care / Accident / Incident Investigation / Litigation / Expert Witness Testimony / Operations and Maintenance / OSHA-related
North America