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tions for optimizations and improve- ments, are then presented to the cus- tomer in a detailed report for follow-up. Benefits of structured hoist equipment assessment and testing, according to ABB, include the capability to stay in compli- ance with applicable statutory require- ments, identify shortfalls in preventive maintenance activities and in necessary maintenance training, and properly assess the status of the equipment relevant to its life cycle. Reports that ensue from the ser- vice can be used as statutory documenta- tion, or as tools for maintenance planning and budgeting. "The Hoist Performance Fingerprint is a cost-effective service that provides diagnos- tics, key findings and recommendations in less than a week," said Remy Lanoue, global service manager for ABB's Process Industries business unit. "By assessing and analyzing all electrical and mechanical parts of the hoist system, we offer our customers a compre- hensive service solution from a single source. This holistic concept is unique in the under- ground mining market." Reading the Rope Constant flexing, load strain, abrasion and environmental influences such as heat, humidity and corrosion make life difficult for hoist ropes, and serve as ongoing points of concern that make rope inspec- tion necessary on a regular basis. Visual inspections of hoist ropes are important, and although non-destructive testing (NDT) by electronic means can be helpful in identifying broken wires and metal loss- es, wire rope manufacturers agree that NDT should be combined with eyes-on examinations. Bridon International, a global supplier of wire rope for hoisting applications, offers some useful advice for conducting visual rope inspections. The company cautions that these guidelines are provid- ed as an aid and not a replacement for involvement of a competent person in any inspection. To begin with, particular attention must be paid to those sections of rope which experience has shown to be liable to deterioration. Excessive wear, broken wires, distortions and corrosion are the more common visible signs of deteriora- tion. Wear is a normal feature of rope ser- vice, and the use of the correct rope construction can ensure that it remains a secondary aspect of deterioration. Lubrication may help to reduce wear. • Broken wires are a normal feature of rope service toward the end of the rope's life, resulting from bending fatigue and wear. Local breakup of wires may indicate some mechanical fault in the equipment. Correct lubrication in service will in- crease fatigue performance. • Distortions are usually a result of mechanical damage and, if severe, can considerably affect rope strength. • Visible rusting indicates a lack of suit- able lubrication, resulting in corrosion. Pitting of external wire surfaces be- comes evident in some circumstances. Broken wires ultimately result. • Internal corrosion occurs in some envi- ronments when lubrication is inade- quate or of an unsuitable type. Reduc- tion in rope diameter will frequently guide the observer to this condition. Confirmation can only be made by opening the rope with clamps or use of spike and needle to facilitate internal inspection. In addition to these fundamental inspection points, look for other possible factors that affect rope performance, Bridon said. Multilayers of rope on the drum can result in distortion in the underlying layers. Bad coiling (due to excessive fleet angle or slack winding) can result in mechanical damage such as severe crushing, and may cause shock loading during operation. Small diameter sheaves can result in a permanent set in the rope, and will lead to early wire breaks due to fatigue. Oversize grooves offer insufficient sup- port to the rope, leading to increased localized pressure, flattening of the rope and premature wire fractures. Grooves are deemed to be oversize when the groove diameter exceeds the nominal rope diam- eter by more than 15% in steel or 20% in polyurethane liners. Undersize grooves in sheaves will crush and deform the rope, often leading to clear patterns of wear and associated wire breaks. Excessive fleet angle can result in severe rope wear due to scrubbing against adja- cent laps on the drum. Rope deterioration at the termination may be exhibited in the form of broken wires. An excessive fleet angle can also induce rotation causing tor- sional imbalance. (Fleet angle, according to Bridon, is usually defined as the included angle between two lines — one that extends from a fixed sheave to the flange of a drum and the other that extends from the same fixed sheave to the drum in a line perpen- dicular to the axis of the drum.) o p e r a t i n g i d e a s c o n t i n u e d January 2016 www.coalage.com 39 Information flow map for ABB's Hoist Performance Fingerprint service.