Shackles are the little (or big) workhorses of the industry. They are used to connect slings and other rigging to loads. While commonly used, they are also commonly abused and used beyond their specifications without much thought.
To help educate readers here are few basic Do’s and Don’ts for lifting when using shackles:
- Always perform a pre-use inspection before each lift (this is required by law) this is especially important when a shackle is installed on a semi-permanent basis to connect a particular item. Do not use the shackle if it doesn’t meet standards or shows any cause for concern.
- For over head lifting operations, shackles with screw pins or bolts must be used.
- Hand tighten the shackle pin when using. Do not back off the pin once the pin shoulder contacts the shackle body.
- When lifting with one sling, make sure the sling is centered (0 – 5 degrees) in the bow of the shackle for maximum capacity.
- If the sling is being pulled to the side (6 – 90 degrees), with no pull on the opposite side, then the rated capacity must be reduced according the
manufacturer’s side loading reduction chart. See Figure 1.
- If a shackle is being used with two slings, and is symmetrically loaded, the maximum included angle of 120-degrees may be utilized up to the full Working Load Limit (WLL) if the manufacturer allows. See Figure 2.
Do not replace shackle pins or bolts with standard bolts or any other object—always use the exact replacement pin from the manufacturer.
- Do not rig a screw pin shackle in a way that would allow the pin to unscrew (i.e. running the sling body over a shackle pin where it can move and eventually unscrew the pin). See Figure 3.
Do not place multiple sling legs against the shackle pin; instead they should be placed in the shackle bow. See Figure 4.
- Do not force a shackle that is too small onto a hook; instead use the correct size shackle or master link that ensures proper load bearing contact with the hook.
If you have more questions on shackles, comment below. Remember that Safety through Education is more than just our motto, it is our guiding principle. If you need training on proper application on this or any other rigging hardware, we have both Qualified and Certified Rigger Level 1 and 2 courses available with Open Enrollment and On-Site options. Reach out to us 1-800-290-0007. We are here for you.
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