Failed Oil Field Ball Valve

A ball valve failure on a wellhead during an oil field hot oiling operation resulted a fire and fatality. An overall view of the failed ball valve is shown in Photograph A.

Photograph A: Overall view of failed oil field ball valve.

A metallurgical failure analysis of the ball valve was requested. The metallurgical failure analysis revealed that very minimal mating between the subject ball keeper threads and the ball valve body threads was present. This indicated a physical size discrepancy and thus a defect in cutting the ball valve body threads during manufacturing, i.e. manufacturing defect.