Grade 30 chains are used for general-purpose chains in agriculture and industry and are not generally used for lifting at height, but for felling, fencing or securing goods.
Grade 43 chains are also not generally used for overhead lifting, but for applications such as logging, securing cargo, shipping and hauling.
Grade 70 chains are generally used as lashing chains and transport chains. Not generally used for overhead lifting, they are rated approximately 20% higher than Grade 43 chains and are made from alloy steel, a higher strength, heat treated chains, typically used for trucking, logging, securing goods on the road, hauling, strapping and towing.
Grade 80 chains are heat-treated, higher strength alloy steel chains with higher strength and lower weight and are mainly used for overhead lifting, but also for lashing and rigging.
Grade 100 chains are approximately 25% stronger than Grade 80 chains and are mainly used for overhead lifting, but can also be used for the same applications as Grade 30 chains to Grade 80 chains. As the strength is high enough, the price will of course be correspondingly high.
Generally speaking, welded chains are available in Grade 30, Grade 43, Grade 70, Grade 80, Grade 100.
The higher the grade, the stronger the chains are and the more resistant they are to compression and breakage. This is because the material used is usually harder, more wear-resistant and more resistant to compression. The strength-to-weight ratio increases and the working load limit (WLL) increases.
The main difference between the different Grades is that Grade 30, Grade 43 carbon steel chains, and Grade 70 chains are not recommended for overhead lifting, while Grade 80, and Grade 100 chains of alloy steel chains are recommended for overhead lifting and rigging.
Improper storage of alloy steel chains; failure to inspect chains frequently enough for the frequency of use; lack of attention to the WLL of the slings, improper or overloaded use of the slings
It is important that your chains are properly maintained and stored, as this is essential for the safety of personnel and the life of the equipment. By maintaining your chains, you will reduce the number of loads falling, injuries to personnel, damage to property etc.
It is important to note that Grade 70 chains should not be used for direct attachment and lifting of loads like slings, as they do not meet the WLL, strength to weight, stiffness and elongation requirements of Grade 80/100 chains. Grade 70 chains do not have the pressure and strength required for overhead lifting.