This article is Part 2 of a 5-part blog series that will cover what professional riggers should consider when performing an in-depth alloy chain sling inspection. Today, we’ll discuss nicks and gouges.
Figure 2 shows nicks of varying degrees of severity. Reading clockwise, at three o’clock there is a longitudinal mark in a compressive stress area. Since it is longitudinal and located in a compressive stress area, its effect is mitigated, but good workmanship calls for it to be filed out by hand.
At about five o’clock there is a deep transverse nick in an area of high shear stress. A similar nick is located at six o’clock in the zone of maximum tensile stress. Both of these nicks can create a potentially dangerous escalation of the local stress and must be filed out with careful attention to not damage other parts of the chain link or chain. A nick that was located at eight o’clock has been filed out properly. Although the final cross section is smaller, the link is stronger because the stress riser effect of the notch has been removed. The remaining cross section can now be evaluated for acceptablity by measuring it and applying the criterion for worn chain. See the “Wear Allowances Table” below.
- In-Depth Alloy Chain Sling Inspection Part #1: Twisting & Bending
- View our Chain Sling Inspection Safety Webinar
- Want to get trained? Check out our Qualified Rigger 3-day Workshop.