A choke bean used in an oil–gas field has catastrophically failed during operation. It is shown that that the damage has been caused by leakage of the corrosive and abrasive drilling fluid. The choke bean adapter made of carbon steel has been corroded and embrittled by hydrogen ingress leading to its fracture in the presence of stresses created by the pressure of accumulated fluid at the bottom section. On the other hand, the choke corner body made of stainless steel has been damaged by abrasive wear of its outer surface.
Tawancy, H. M., & Alhems, L. M. (2016). Damage analysis of choke bean used in an oil–gas well. Case Studies in Engineering Failure Analysis, 7, 56–64. https://doi.org/10.1016/j.csefa.2016.08.001