How to choose a chain sling for rigging？

In lifting operations, a chain sling is a common and reliable piece of equipment. It has the characteristics of high strength and durability, and is suitable for lifting heavy objects.

1. The two basic types and compositions of chain slings

The lifting chain sling structure mainly includes a lifting chain, a lifting ring + butterfly buckle, and a hook. This is a combination of 1-4 legs.

Another kind of chain rigging is composed of a chain and a hook, such as G80 Binder Chain With Eye Bent Hook.The Tie Down Link Chain mainly realizes the role of strapping weight, and the hook can hook the chain link, so as to play the role of knotting and bundling.

2. Consider the weight of the object being lifted

Each type of chain slings has a rated load capacity, exceeding which may cause the chain sling to break or fail. Therefore, when choosing a chain sling, you need to make sure that the rated load capacity of the sling at least matches the weight of the lifting object, and it is best to leave a certain safety margin.

When calculating the weight of a hoisted object, the following formula can be used:

The β value of the hoisting angle (plumb line) is 0~45°: P=1.4

The β value of the hoisting angle (plumb line) is 45~60°: P=1

WLL=P × Load rating for a single limb chain rigging

3. Consider the shape of the hoisting object and the hoisting angle

The size of the hoisting angle will produce different tensions on the binder chain in general, the larger the hoisting angle, the greater the force of the chain sling, and the smaller the weight that can be carried. Therefore, it is recommended to choose the β angle at 0~45° as the best (according to the above load-bearing calculation formula).

If the hoisted object is an irregular shape, it may need to be fixed with a binding chain or hoisting belt, so as to ensure that the heavy object does not shake and is lifted smoothly during hoisting. The lifting strap can increase the contact area with the object being lifted, and the multiple lifting points can also distribute the weight and reduce the load of a single sling.

4. Material and durability selection

The material of the alloy chain sling is usually alloy steel or carbon steel, and it is best to choose G80 strength grade and 4 times the safety factor.

Among them, alloy steels generally have better tensile strength and wear resistance.

If it is in harsh environments, such as abrasive or corrosive buildings, dyes, etc., the corrosion resistance and heat resistance of the chain sling are particularly important. Choose a chain sling with an anti-rust coating, stainless steel or even explosion-proof chain rigging, or increase the class of use, such as a G100 mining chain.

5. Choose the right chain length

The length of the chain sling depends on the lifting height, as well as the size of the weight from the lifting ring, in order to ensure a safe lifting angle, the chain rigging length can not be too short. If the sling is too short, it may lead to difficult lifting operations and affect safety.

But if the chain sling is too long, it will increase the waste of working space and may lead to the instability of the lifting object, so if you want to meet a variety of lengths, you can also choose adjustable chain sling.

Common chain sling lengths are 1 meter, 2 meters, 3 meters, etc.

6. Choose the right type of chain sling

Chain slings come in a number of different types, including:

• Single leg chain sling

• 2 leg chain sling

• 4 leg chain sling

A single chain sling is suitable for lighter lifting objects, while a multiple chain sling is suitable for heavier or irregular objects, making it easy for multiple lifting points to balance and share the weight.

7. Know the load rating of the chain sling

Each chain sling has a load rating, which is the maximum load it can withstand under standard lifting conditions. When choosing a chain sling, it's important to know the load rating and make sure it meets the requirements of the lifting task. For safety, it is recommended that the rated load of the chain sling selected should be greater than the weight of the actual lifting object.