TT Talk - The Importance of Regular Structural Examinations of Quay Cranes
Based on an analysis revealing a number of major structural failures in port equipment in recent years, Laurence Jones, TT Club's Global Risk Assessment Director, stresses how essential it is for operators of ports and cargo handling facilities to establish a regular sequence of maintenance and thorough examination of all the lifting appliances it utilises. "Provisions for such examinations are specified in ILO Convention 152 and its accompanying Code of Practice, and represent the international standard for the port industry. The purpose of a thorough examination is to make sure a crane can continue working safely and effectively, and a crucial element of this with regard to a quay crane is the safety of its structure," Jones emphasised. installation and commissioning to check for quality and conformance to standards and specification - beyond the ILO Convention requirement. Once commissioned, a crane should also be examined regularly during its operational life, regardless of how good its manufacture. Damage resulting from relatively minor impacts, regular heavy-lifts close to, or equal to the safe working load limits, intensive use or simply general wear and tear can affect the integrity of the crane's structure. Often such operational issues can occur without anybody being aware, so regular examinations need to be conducted. Any known incident should clearly result in a check on the structural integrity of the crane at that time. This advice applies equally to fixed and mobile cranes of any type.
The Club recommends that independent examinations are always performed when procuring any type of crane. The ILO Convention requires that before being brought into commission for the first time, lifting appliances are tested and a thorough examination carried out. The Club also recommends that appropriate mechanical and electrical inspections are carried out during
The ILO standard calls for a competent person to carry out the testing and thorough examinations. It is common practice to utilise third party inspection companies to check for quality and design conformance during manufacture. Laurence Jones recommends that only specialist inspection companies should be used, such as Bureau Veritas, Lloyd's Register, Liftech Consultants and World Crane Services. These companies provide examinations globally during and after manufacture, although it is clear that there are other equally competent and locally based service providers. Thorough examinations during the life of the crane should fall within a strict maintenance policy that is seeking to maximise its useful life and minimise unplanned downtime.
The Club's analysis indicates that the actual structure of a crane, because of its size and complexity, may not always be examined as often as it should. The standard calls for such examinations to be conducted at least once every twelve months. Generally, as a crane gets older the examination frequency should increase. Furthermore, the regularity of examinations should increase based on the degree of use and if this is at or close to the crane's safe working load limits.
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