AS 3775.1:2014 Chain slings for lifting purposes—Grade T(80) and V(100)
To create a basket sling using shorteners (see Figure 8(d)) where two connectors are load bearing. The master link shall have capacity for the working load limit.
NOTE: Serious incidents have occurred from the failure of the joining device by misuse of shortening grab hooks inducing side loading. By having the shortening grab hook on a separate joining device, the potential for human error is reduced, however in some applications this may not be possible, e.g. height constraints, overcrowding of intermediate link.
8.1 Proof loading
One or more of the following shall apply:
(a) Each single-leg sling and each sling leg of a multi-leg sling shall be subjected to a proof force that is not less than [(WLL in tonnes) × 9.81 × 2] kN applied under the conditions specified in Appendix D and examined by a competent person. Each multi-upper-terminal link and each intermediate link of a multi-leg sling shall be subjected to a proof force of [(WLL for a single leg in tonnes as specified by Table D1 or D2) × 9.81 × 1.73 × 2] kN. NOTE: The factor 1.73 represents multi-leg sling loading at 60° as calculated in Columns 6 and 7 of Table D1 and D2. Regardless of any modified WLL, the proof load test force shall be in accordance with Tables D1 or D2.
(b) Proof testing of an assembly with mixed grades of components shall be proof tested to the lowest rated component.
(c) Where all of the components of a sling have been proof tested, but any component has been subjected to further manufacturing or modification subsequent to any earlier proof testing, the completed sling shall be subjected to further proof testing and examined by a competent person.
(d) Assembled slings shall be proof tested and shall be visually examined by a competent person. Adequate records shall be maintained.
(e) Slings that have had damaged load-bearing components replaced shall be proof tested.
(f) Slings with missing tags shall be inspected by a competent person to ensure integrity and identification of components and shall be proof tested and re-tagged.