Reverse bends. Overload and shock loads. Excessive rope vibration. Kinks that have formed and have been straightened out. Crushing and flattening of the rope. Sheave wobble. Corrosion Inadequate lubrication. Improper storage. Exposure to acids or alkalis. Kinks Improper installation. Improper handling. Slack rope pulled tight. Excessive Localized Wear Drum crushing. Equalizer Sheave.
Stretch Overload. Passed normal stretch and approaches failure. Fittings get pulled too close to sheave or drum. This condition is normal. However, if diameter reduction is isolated to one area or happens quickly, the inspector must immediately determine and correct, if necessary the cause of the diameter loss, and schedule the rope for replacement. Crushing or flattening of the strands can be caused by a number of different factors.
These problems usually occur on multilayer spooling conditions but can occur by simply using the wrong wire rope construction.
Failure to properly break-in the new rope, or worse, to have no break-in procedure at all, will cause similar poor spooling conditions. Therefore, it is imperative that the inspector knows how to inspect the wire rope as well as how that rope was installed.
Shock loading bird-caging of the rope is another reason for replacement of the rope. Shock loading is caused by the sudden release of tension on the wire rope and its resultant rebound from being overloaded.
The damage that occurs can never be corrected and the rope must be replaced. High stranding may occur for a number of reasons such as failure to properly seize the rope prior to installation or maintain seizing during wedge socket installation.
Sometimes wavy rope occurs due to kinks or a very tight grooving problem. Another possibility is simply introducing torque or twist into a new rope during poor installation procedures. This condition requires the inspector to evaluate the continued use of the rope or increase the frequency of inspection. Basic Guidelines of Wire Rope Inspection. Troubleshooting Wire Rope Abrasion Abrasion damage may occur when the rope contacts an abrasive medium or simply when it passes over the drum and sheaves.
Excessive stretch or sharp reduction in the rope diameter. Knots or splices except eye splices in a wire rope. Missing sling identification, such as manufacturer, workload limit, diameter or size.
Wear on areas that are in contact with hoist sheaves and drums. Corrosion from lack of lubrication and exposure to heat or moisture e. Fatigue from repeated bending even under normal operating conditions. Overloading the safe working load limit. Follow manufacturers' charts. Mechanical abuse - crushing, cutting or dragging of rope.
Being used when frozen - if work is performed at lower than Kinks from the improper installation of new rope, the sudden release of a load or knots made to shorten a rope. A kink cannot be removed without creating a weak section. Discarding kinked rope is best. Kinked wire rope. Document last updated on August 28, Document confirmed current on April 3,
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