| 摘要 |
<p>A pre-failure warning indicator (11) is provided for use with a sling (10) . The pre-failure warning indicator (11) triggers at a point that is predictable within a relatively narrow range, thereby increasing the possibility that a damaged sling (10) is removed from use. The pre-failure warning indicator (11) includes a dedicated strand of material (20) that is placed in close proximity to the load-bearing core yarns (17) of the sling (10) but remains separate and independent from the core yarns (17) ; the ends (22,24) of the dedicated strand are connected via a sacrificial "ring" (26) . A warning fiber (29) having an end that is visible to operators/riggers works in conjunction with the sacrificial strand (20) and the ring (26) . The ring (26) is designed to fail when the sling (10) is subjected to a specifically chosen condition (e.g., excessive weight) . The failure of the ring (26) causes the warning fiber (20) to withdraw from the rigger' s view thereby warning the rigger that the sling (10) was subjected to the specifically chosen condition and may be damaged.</p> |
