The types of metal components used in lifting equipment include gears, shafts, drums and sheaves, brakes, brake wheels, couplings, bearings, wheels, electrical switchgear, chains, wire rope, and hooks. This article primarily deals with many of these metal components of lifting equipment in three categories: cranes and bridges, attachments used for direct lifting, and built-in members of lifting equipment. It first reviews the mechanisms, origins, and investigation of failures. Then the article describes the materials used for lifting equipment, followed by a section explaining the failure analysis of wire ropes and the failure of wire ropes due to corrosion, a common cause of wire-rope failure. Further, it reviews the characteristics of shock loading, abrasive wear, and stress-corrosion cracking of a wire rope. Then, the article provides information on the failure analysis of chains, hooks, shafts, and cranes and related members.

This article describes the techniques for measuring friction, namely, inclined-plane method; friction test methods using weights and pulleys; friction tests of shafts and capstans; other types of friction tests, including standards; microscale friction tests; and friction testing under well-lubricated conditions. The procedural considerations that should be addressed to ensure that valid data are derived from a friction test are discussed. The article explains friction testing geometries, the major considerations implicit in their use as well as friction test parameters, such as speed and load. It also demonstrates how to report friction data and how these data can be entered into a database.