Whenever you lift a load with the legs of a sling at an angle, you can calculate the actual load per leg by using the following threestep formula. Wire rope safe working load the term safe working load swl of wire rope means the load that can be applied and still obtain the most efficient service and also prolong the life of the rope. Home catalog rigging information wire rope sling capacities. The rated capacity of a wire rope sling is based upon the minimum breaking force mbf of the wire rope used in the sling and other 2 union a wireco worldgroup brand dd ratios when a sling is rigged as a basket, the diameter of the bend where the sling contacts the load can affect the sling s lifting capacity. Length tolerances single part wire rope slings standard length tolerance is plus or minus two rope diameters, or plus or minus 0. The wire rope sling capacity tables presented later in this section take these and other factorsincluding design factorinto account when presenting wire rope sling capacity. Sir kisi jib ya davit bmu ka load calculation pr bi ak video bnana. It has a single wire center with six wires of the same diameter around it. Quality continuum quality continuum wire rope end fittings wire rope end fittings shackles shackles sling saver fittings sling saver fittings hooks. Enter a page number in the box below to jump to a specific page. Single part body, mechanicallyspliced wire rope slings flemish eye splice in the standard.
The load must also have certified lifting points or be relatively easy to sling. Single part body mechanical splice slings have a higher rated capacity than hand spliced slings. For a 26mm wire rope to escape bend fatigue the winch drum or block sheaves over which it runs would need a minimum diameter of over 1. Pdf introduction to sling load tension calculations. Equipment operator basic beginning construction equipment operators manual. How wire rope slings are used hitches how wire rope slings are configured to lift a load is called a hitch. Basic rigging workbook training brookhaven national laboratory. When a wire rope sling is used in a basket hitch, the diameter. The amount of wire rope needed for the system is determined by multiplying the number of parts of line by travel distance of the load plus enough wire rope to.
For example, a reeved sling around a square load will halve the sling s lifting capacity. Take the guess work out of how much force is exerted on a sling when making a lift with two or more lifting straps. Page navigation 334 335 336 337 338 339 340 341 342 343 344. Vertical eye and eye hitch if one eye of the sling is attached to the lifting hook and the other eye is attached to the load, this is called a vertical eye and eye, or straight, hitch. Rule of thumb methods for calculating the swls of flexible steel wire rope. How to calculate safe working load of wire rope slings swl of wire. How to calculate safe working load swl of wire rope slings. The rated capacity of a sling and what it means to you t. The formula for computing the swl of a wire rope is the diameter of the rope squared, multiplied by 8 d x d x 8 swl in tons. See page 91 for reduced choker capacity when using these hook sizes. Pdf when slings are used to lift loads, safety professionals must ensure the weight does not exceed the safe working load limit wll of the sling. Wire rope sling splices there are three basic splice types. Therefore a fswr sling of at least 12 mm in diameter is required to lift a 1152 kg load for a. This is clearly impractical in many applications, and unnecessary if.