Large materials handling machines such as stackers, reclaimers and shiploaders are typically of welded steel construction balanced by a large counterweight. They are
normally capable of long traveling, slewing and luffing motions and must withstand repetitive dynamic loads. Historically, such machines have experienced higher failure
rates than other types of structures. The main risks are typically machine collisions, corrosion and structural fatigue cracking. The structural integrity of a machine is dependent on the structural, mechanical, electrical, and control systems operating correctly. The distinguishing feature of mobile equipment for continuous handling of bulk materials is the inherent high level of risk and the very large cost of addressing the failure consequences. This difference justifies specific processes to manage this risk.