sling. The total weight of the load is carriedby a single leg with the sling angle of 90degrees.Bridle HitchThe bridle hitch can consist of two,three, or four single hitches (fig. 3-22), usedtogether to form a bridle hitch for hoisting anobject.The bridle hitch provides excellent loadstability when the load is distributed equallyamong the legs, the load hook is directly overthe center of gravity of the load, and the loadis raised level. The use of a bridle slingrequires that the sling angles be carefullydetermined to ensure that the individual legsare not overloaded. It is wrong to concludethat a three- or four-leg bridle hitch willsafely lift a load equal to the safe load on oneleg multiplied by the number of legs, becausethere is no way of knowing that each leg iscarrying its share of the load. With a four-legged bridle sling lifting a rigid load, it ispossible for two of the legs to take practicallythe full load while the other two only balanceit. COMSECOND/COMTHIRDNCB stronglyrecommend that the rated capacities for two-leg bridle slings listed in the COMSECOND/COMTHIRDNCBINST 11200.11 series be usedalso as the safe load of three- or four-legbridle hitches.Sling AngleThe rated capacity of any sling dependson the size, the configuration, and the anglesformed by the legs of the sling and thehorizontal. A sling with two legs used to lift a1,000 pound object will have 500 pounds of theload on each leg when the sling angle is 90degrees. The load stress on each leg increasesas the angle decreases; and if the sling anglewas 30 degrees lifting the same 1,000 poundobject, the load will be 1,000 pounds on eachleg. Try to keep all sling angles greater than45 degrees; sling angles approaching 30degrees are considered extremely hazardousand must be avoided at all cost.Sling Safe Working LoadsIt is a difficult task to remember all of the load,size, and sling combinations; however, the followingFigure 3-22.—Bridle hitch.rules of thumb work well for estimating theloads in the most sling configurations.The rules of thumb are based on thesafe working load of the single vertical hitchof a particular sling. The efficiencies of theend fittings used also have to be consideredwhen determining the capacity of thecombination.3-23
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