Under what condition should wire rope be deemed unsafe to use?

Wire rope should be deemed unsafe to use if it shows signs of excessive wear or corrosion. This condition is critical because excessive wear can lead to a significant reduction in the rope's strength and load-bearing capacity. As wire rope is subjected to tension, bending, and abrasion, its structural integrity can be compromised. Corrosion can similarly weaken the wires, making them brittle and prone to breaking under load. Regular inspection for these signs is essential in ensuring safety when using wire rope in various applications.

While visible rust might raise concerns, it does not necessarily indicate that the rope is unsafe at a glance, as some rust can be surface-level and not compromise the rope's overall strength. A wire rope that is longer than 10 diameters may be structurally sound as long as it meets other safety criteria and standards. Being frayed on both ends is indeed a factor to consider, but the key determinant for safety lies in overall wear and corrosion, which directly affects the performance and reliability of the wire rope under load.