4 Leg Chain Sling Capacity Chart

In the field of modern industrial lifting, 4 leg chain rigging has become a core tool for heavy equipment, steel structure, shipbuilding and other scenarios by virtue of its high load capacity and flexibility.

I. Core elements of weighing capacity of limb chain rigging  

1. Material and grade determine the base strength  

For example, adjustable chain sling is usually made of G80 grade and above alloy steel, its tensile strength is up to 800MPa, and the safety factor can be up to 4-6 times. For example, the rated load of single limb of 40T specification rigging can reach 7.1 tons (when the lifting angle is 80°), and it can still maintain more than 90% performance under extreme temperature (-40℃ to 200℃).  

2. The effect of lifting angle on the actual load

Angle is the key variable of weighing capacity, take 40T four limbs rigging as an example:  

• 0° (straight lifting): 5 tons load per limb, total load 20 tons;  

• 60°: 5.8 tons per limb, total load 23.2 tons;  

• 120°: 10 tons per limb, total load 40 tons.  

The larger the angle, the smaller the single limb force, but it should be noted that multiple limbs need to be evenly distributed through the sub-mother ring when the force is coordinated.  

3. Structural design and accessories adaptability 

Four-limb rigging can also be realized through the butterfly buckle, adjuster and mother and son ring to achieve the same length of the limbs, reduce wear and prolong the service life. One of the hooks can be changed to different types, such as Clevis Grab Hook or Open hook eye clip locking, etc., to enhance lifting stability.

II. the practical formula for scientific calculation of weighing capacity

1. Formula method to simplify the calculation 

For multi-limb rigging, the actual load needs to be adjusted in combination with the angle coefficient. For example:  

Single Leg Chain Sling = 1 times its own load

2 Leg Chain Sling = 1.4 × single-limb rated load (angle ≤ 45 °);  

4 Leg Chain Slings= single-limb load × 4 × angle coefficient.  

For detailed weighing table data, please click on the link of the rigging product corresponding to the above formula and read from the parameter table position.

2. Customized Parameter Matching Requirements 

If it is difficult to calculate on your own, you can directly provide the manufacturer with the lifting scenario parameters (e.g., shape of heavy load, temperature environment) to customize the rigging with clear load labeling. For example, as a Chinese supplier of chain rigging, we provide 40T rigging with “120° angle full load 40 tons”, which is suitable for complex lifting scenarios such as steel coils and shaped molds.

III.Application Scenarios and Safe Operation Recommendations

1. Typical application fields 

- Heavy industry: multi-angle lifting of ship equipments and bridge steel components;  

- Warehousing and logistics: balanced handling of steel coils and pipes;  

- Extreme environment: high temperature workshop (≤200℃) or low temperature harbor (≥-40℃).  

2. Safety specification and maintenance

- Check before use: make sure the chain is not worn or deformed and the hook locking mechanism is intact;  

- Avoid overloading: strictly prohibit exceeding the maximum load under the labeled angle, and the rated load should be reduced by 20% when bundling operation;  

- Regular maintenance: clean the oil on the surface of the chain and check whether the heat treatment part is oxidized.

IV.Industry Trend and Selection Guide

With the development of industrial automation, four-limb chain rigging is being upgraded in the direction of high strength and modularization. For example, some manufacturers have introduced adjustable chain (length ± 10%), adapted to dynamic lifting needs. You can refer to this article to help yourself choose the right product: How to choose a chain sling for rigging？

1. Matching load rating: Give priority to materials above G80 grade. 2;  

2. Scene suitability: additional verification of heat resistance is required for high temperature environments;  

3. certification standards: rigging needs to pass ISO, CE and other certifications to ensure compliance.