How to Choose the Right Sling for Rigging and Lifting Objects

Choosing Between Chains, Slings and Other Rigging Tools

Every time we are trying to hoist or do some rigging, multiple tools can be used, but how do you know if that is that is the right sling or chain? Every load must be carefully inspected and assessed before being lifted, and you should know about the edges, positioning and how the load is going to be moved. The following list provides some guidelines and information on how to choose the right sling or chain for your construction needs. It is important to highlight that slings or chains with knots in any part of them must not be used, as the loading rating of the sling can be diminished by more than 50 percent.

1
Wire Rope Slings

Wire Slings
Wire Slings. Photo Antarias

Wire rope slings are very durable offering great strength and flexibility during the lifting and hoisting process. Also called wire cable slings, they can be used and will last longer than nylon ones, can be used and are recommended when there is a concern in regards to heat and higher temperatures.

However, it is very important to protect its edges as it can be damaged when in constant contact with corners or very sharp edges. There are softeners available that can be placed strategically to prevent damages to the wire rope sling.

Wire rope slings of all types should never be used when in contact or when the temperature falls under -40 degrees (F). In the construction industry, the most used wire rope sling is either the 6 x 19 or 6 x 37. Be aware that slings used in areas near acidic components, the wire might get corroded easily, so frequent inspections are needed. If you are conducting a pre-inspection be sure to look for broken wires, corroded components and kinking. 

2
Web Slings

Nylon sling
Nylon sling. Photo Matti Mattila flickr

Web slings can be a very good choice whenever you are in doubt. Web slings are flexible and tend to adjust to the shape of the load being handled. These type of slings will reduce twisting and spinning, will not rust and will serve to protect the load as well. Another important advantage is that they can stretch and can elongate without breaking.

However, one big disadvantage is that they can be easily damaged due to sharp edges and corners and they cannot withstand heat over 194 degrees. They are normally made out of polyester or nylon, but both should be stored carefully and avoiding having them stored under the sun.

Nylon slings are normally identified with their size, type, and load rating limits. The sizing of a nylon sling will be determined by the width of the web. Nylon slings have a red marked built into them, that when exposed, the sling shall be discarded for use, as it means that the nylon has suffered too much elongation and could be susceptible to failure. A nylon sling shall be removed from their service if you notice one of the followings:

  • Melting
  • Holes
  • Tears
  • Frayed fibers on the nylon surface

3
Chain Slings

Chain sling
Chain sling. Photo ella_k

Chain slings can be used to lift heavier loads and will do great when high temperatures are expected. However, one of the most important things to highlight is that chain slings will not provide a means to discover when they are about to fail, It has been found that sling chains can fail without notice when the load exceeds the allowable capacity.

It is preferable to have chains made of steel alloys (grade 80 or 100), but it would be better if a wire rope sling is used. Another important aspect is that the inspection of the slings is more challenging, as it needs to be done on a link by link basis to ensure that there are now marks of creep or visible wear and tear marks.

Normally, chain slings contain a tag providing the length of the chain, so when the chain is shorter than the indicated length, it would not be used and should be removed from the site. When using one of these slings the following must be ​checked prior to use:​​

  • Cracks, nicks and gouges on every link
  • Elongation marks
  • Heat damage
  • Hooks
  • Twisted links

4
Rope Slings

Rope sling
Rope sling. Photo Moritz320

Ropes can be used to hoist ​tools and equipment but it will require some special knowledge on ropes and their conditions. Ropes are recommended for lifting smaller tools and objects, normally using pulleys, or any other mechanism that can be operated by hand, rather than mechanical equipment. One of the best uses for ropes is as tag lines, to maintain control of objects.

However, it is common to see ropes with knots and the rope strength should be known to make sure you are not exceeding the weight limits. Ropes should not be used if the following issues are detected upon inspection:

  • Abnormal wear
  • Powder between strands
  • Cut fibers 
  • Changes in size or diameter
  • Discoloration or rotting

5
Metal Mesh Slings

Metal Slings
Metal Mesh Slings. Photo www.wireropeslings.com.au

Metal mesh also referred to as wire mesh slings are the preferred option when the object being lifted could cut wire rope slings. It is also used on hot or abrasive objects. Many pre-fab or pre-stressed concrete manufacturers tend to use these type of slings to control and handle the objects efficiently. Wire mesh slings will firmly grip the load and will create tight chokes preventing the load from slipping while maintaining balanced loads. It is best when the metal sling has not been painted, in the case that they are being used in high-temperature environments.

Be sure to check the sling for broken wires, mesh distortion or broken weld. It is very important to determine the load rating of the end fittings to make sure they match the sling load rating.

6
Sling Fittings

Shackle
Shackle. Photo Crosby Rigging

When using any of these options, consider having the following attachments or fittings to make proper use of the sling:

  • Wire Rope Thimbles
  • Turnbuckles
  • Hoist Rings
  • Eye Bolts
  • Swivel Hooks and Swivels
  • Wire Rope Clips
  • Shackles