Care & Use of Shackles

A critical component of lifting & many other applications. Shackles should always be kept, cared for and used in the following ways.

*This information contained in this guide has been supplied courtesy of Van Beet B.V, The Netherlands.

Inspection

Shackles should be inspected before use to ensure that:

Shackles should be inspected before use to ensure that:
All markings are legible
The body and pin are both identifiable as being of the same size, type and make
The threads of the pin and the body are undamaged
The body and the pin are not distorted or unduly worn
The body and pin are free from nicks, gouges, cracks and corrosion
Shackles have not been heat treated.

It is required that the shackles are regularly inspected as they may be affected by wear, misuse, overloading etc. with a consequence of deformation and alteration of the material structure

Never

Use a safety bolt type shackle without using a security pin.
Immerse a shackle in acidic solutions or expose to acid fumes or other chemicals that are potentially harmful to the shackle. Please be aware that these types of chemicals are used in certain production processes.
Modify, repair or reshape a shackle by machining, welding, heating or bending as this will affect the working load limit.
Use a commercial (uncertified) shackle for lifting applications.
Replace a shackle pin except with one of the same size, type and make.

Selection

Select the correct type of shackle and its working load limit for the particular application. Should extreme circumstances or shock loading be applicable, this must be well taken into account on selecting the correct shackle.

Assembly

Ensure that the pin is correctly screwed into the shackle eye, i.e. tighten hand-tight, then secure using a wrench or other suitable tool so that the collar of the pin is fully seated on the shackle eye. Ensure that the pin is of the correct length so that it penetrates the full depth of the screwed eye and allows the collar of the pin to seat on the surface of the shackle eye.

Incorrect seating of the pin may be due to a bent pin, too tight fitting thread or misalignment of the pin holes. Do not use the shackle under these circumstances.

Make sure that the shackle is supporting the load correctly, i.e. along the axis of the shackle body centreline, avoid introduction of bending loads or unstable loads. Do not overload.

Side Loads

Side loads should be avoided wherever possible. If side loads cannot be avoided,the following reduction factors must be taken into account:

Load Angle	New Working Load Limit
0°	100% of original WLL
45°	70% of WLL
45°	50% of WLL

In-line loading is considered to be a load perpendicular to the pin and in the plane of the bow. Load angles in the table are the deviating angles from the in-line loads. When using shackles to connect multi-leg slings, due consideration should be given to the effect of the angle between the legs of the sling. As the angle increases, so does the load in the sling leg and consequently in any shackle attached to that leg.

Angle between the slings

When a shackle is used to connect two slings to the hook of a lifting device, a bow type shackle must be assembled with the slings in the shackle body and the hook engaged with the shackle pin. The angle between the slings should not exceed 120°. If symmetrically loaded the shackle may be used to the full WLL.

To avoid eccentric loading of the shackle a loose spacer may be used on either end of the shackle pin. Do not reduce the width between the shackle jaws by welding washers or spacers to the inside faces of the eyes or by closing the jaws, as this will affect the properties of the shackle.

When a shackle is used to secure the top block of a set of wire rope blocks, the load on this shackle is increased by the value of the hoisting effect. Avoid applications where due to movement (e.g. of the load or the rope) the shackle pin can rotate and possibly be unscrewed. If such an application is necessary or when the shackle is to be left in place for a prolonged period or where maximum pin security is required, use a shackle with a safety bolt, nut and cotter pin.

Series of drawings of shackles attached to rope in different formations

Point Loading

Most of the time the load bearing component that is in connection with a shackle is of a rounded shape. Point loading of shackles is allowed but the minimum diameter of a rounded component should be equal or bigger than the bow size of the shackle being used.

Bigger diameters and/or flat parts (at shackle pin side) to increase contact area can be beneficial. Sharp edges should be avoided.

Temperature

If extreme temperature situations are applicable, the following load reduction must be taken into account:

Temperature	New WLL
<200°C	100% of original WLL
200-300°C	90% of WLL
300-400°C	75% of WLL
>400°C	Not Allowed

Exceptionally hazardous conditions

The rating of shackles to EN 13889 assumes the absence of exceptionally hazardous conditions. Exceptionally hazardous conditions include offshore activities, the lifting of persons and the lifting of potentially dangerous loads such as molten metals, corrosive materials or fissile materials. In such cases, a competent person should assess the degree of hazard and the safe working load (SWL) should be reduced accordingly from the working load limit (WLL).