18.10 SAFE USE OF FIBRE ROPE SLINGS

In addition to any specific instructions relating to the safe use of the fibre rope sling issued by the manufacturer, the following points should be observed:

  1. The sling should be of adequate strength and length; never exceed the SWL for the particular mode of use. Care must also be taken to ensure the compatibility of any ancillary equipment used to sling the load, both in size and capacity. The diameter of components placed in a soft eye must be at least the same as the rope, but preferably twice the rope diameter. Care must be taken to ensure that the two parts of rope at the splice of a soft eye do not form an included angle exceeding 30°.

  2. Where more than one sling is used to lift the load, each sling should be adequate for the share of the load imposed on it taking into account the slinging method. Do not overcrowd the hook of the lifting appliance. It is good practice when using more than one sling to join them with a shackle before placing them onto the hook.

  3. It should be noted that the various fibres used to manufacture rope slings have differing stretch and recovery rates and that the elongation of the sling is proportional to its length. This must be borne in mind in all arrangements using more than one sling. The slings should therefore be of the same material and account must be taken of this if they are of unequal length.

  4. Fibre rope slings have very different stretch characteristics to those of chain or wire rope slings. Their use in parallel with chain or wire rope slings to form multi-leg assemblies should therefore be avoided as the unequal stretch of the legs can lead to load instability. However, this is not intended to preclude their use combined in series as a means of connecting a sling to the load which can be advantageous in some circumstances. For example, a fibre rope sling can be wrapped and choked onto a polished surface then hooked into a chain sling thus gaining the advantage of the fibre rope protecting an easily damaged surface combined with the adjustability of a chain sling.

  5. Position the slings correctly. Use packing protection for sharp edges and, if protective sleeves are fitted, ensure they are correctly positioned to prevent cutting damage to the sling. Keep labels and tags away from the load and the hook as these may damage the sling or themselves be damaged during the lifting operation.

  6. In the case of multi-leg slings and slinging arrangements, the legs should not be disposed at more than 45° to the vertical (90° included angle) or less than 15° to the vertical (30° included angle)

  7. Position the bight for choke lift in the natural (120°) angle to avoid heat being generated by friction which could cause damage to the sling. When using basket hitch, care should be taken to ensure that the load is secure since there is no gripping action as with choke hitch. Movement of the load in the sling will cause abrasion and heat from friction and may result in the load being dropped.

  8. When using endless slings, ensure the splice is positioned in the standing part of the rope away from the load, hook or point of choke.

  9. Great care should be taken to avoid shock loading as it effectively increases the weight of a load and could result in the lifting equipment being grossly overloaded. In particular, man-made fibres have very differing elastic characteristics and, dependent on the material in use, permanent elongation may result from shock loading.

  10. When using fibre rope slings in association with chemicals, ensure the sling material and that of the fittings is suitable. Always follow the manufacturer’s instructions, which may place limitations on the use of the sling. If any doubt exists, seek further advice.