Failed Stabilizing Arm

Metallurgical failure analysis was requested on a failed piece of construction equipment. A stabilizing arm attached to a concrete pumping truck cracked through a weld resulting in an accident.  Metallurgical testing of the weld and surrounding metal was conducted. A finite element design analysis (FEA) was conducted on the stabilizing arm. Metallurgical testing in addition to macro and microscopic examination determined that the cause of the weld crack was metal fatigue. The properties of the weld and surrounding metal were satisfactory. It was determined that the cause of the accident was faulty design and a lack of proper inspection and maintenance.