Chain Working Load Limit

Determining chain working load limits.

Chain working load limit.

It is a rated capacity and often referred to in pounds. The working load limit of the chain must be sufficiently strong to support the load s weight as well as any added forces from the hitch types and angles used. Distribute the load evenly. Do not load an assembly in excess of working load limits shown.

Do not put an unequal load on one leg of a sling. Do not expose assembly to impact rapid lifts or sudden stops. An example of this would be a chain that has a mbl of 2000 lbf 8 89 kn would have a swl or wll of 400 lbf 1 78 kn if a safety factor of 5 5 1 5 to 1 or 1 5 is used. Working load limit wll is the maximum working load designed by the manufacturer.

Working load limit or wll refers to the maximum allowed weight. Do not tie knots or allow chains to become twisted. Chains have a working load limit or wll of approximately one third of their break strengths the amount of force the chains can withstand before they break. So grade 80 is really 800 and grade 120 is 1 200.

Wll mbl sf. Usa roller chain and sprockets is one of the nation s largest suppliers of roller chain and industrial pt components. A chain s wll is the maximum tension that can be placed on an undamaged or brand new chain. Working load limits of chain whether you transport machinery use tow chains or are in the logging industry it s important to know the working load limits of chain you are using.

Therefore a strap with a breaking strength of 15 000 pounds will have a working load limit of 5 000 pounds. The roller chain size charts below will help ensure you purchase the chain that suits your machinery best and provides the strength or load carrying capacity required by your specific manufacturing process. The term working load limit wll refers to the maximum amount of tension that can be applied to a new and undamaged chain. The proof test load usually twice the working load limit is the load which the product withstood without deformation when new and under laboratory test conditions.

A constantly increasing force is applied in direct line to the product at a uniform rate of speed on a standard pull testing machine. Working load limit is always 1 3 of the breaking strength. Table working load limits wll for chain chain size in millimeters inches unmarked chain grade 30 proof coil grade 43 high test grade 70 transport grade 80 alloy grade 100 alloy chain marking none 3 30 300 4 43 430 7 70 700 8 80 800 10 100 1000 7mm 1 4in 580kg 1 300lb 580kg 1 300lb 1 180kg. Working load limit wll of a chain is another designated safety measure.

A winch strap with a wll of 5 000 pounds should not be used to secure any load above that weight.