Delta Rigging & Tools has developed a patent-pending technology that solves what has been a difficult problem with a simple approach: it prevents the removal of shackles from rated slings out in the field by compressing down during manufacturing to a size that prevents the ears of the shackle from passing through.

The device is called the Shackle-Loc Thimble™, and it could help make work safer across a range of industries by ensuring the integrity of rated wire-rope slings and shackles is maintained in the field.

Typically, when a wire rope sling set is manufactured, the shackle is sized precisely for the size and load rating for the wire rope. With a conventional thimble, however, the high-quality rated shackle may be removed and replaced with something of inferior quality.  When this happens, the rated capacity of the sling may be compromised without the next set of users being aware that the shackle has been replaced.

Delta’s patent-pending Shackle-Loc Thimble, once compressed down during the manufacturing of the sling set, prevents the rated shackle from being removed.  It does this through a mechanical barrier that is pre-welded in place that actually reinforces the thimble at the same time.

In the past companies tried to prevent shackle removal by welding a bar onto the thimble to hold the shackle in place. But that is time consuming, raises the operator risk during assembly, and puts torch temperatures next to the wire rope.

With the Shackle-Loc Thimble, you can be sure that the rated shackle put on when the sling set was assembled and the certificate of compliance is issued, is still in place.

It’s a clever design that improves safety without adding significant cost or time. You also only need one compliance certificate for the sling set.