6. Gantry and/or live mast in the highest position.7. Quadrant of operation (that is, over the side, overthe rear capacities).Load Rating ChartAtypical load rating chart is shown in figure 12-47.To determine the capacity of the crane by using the loadchart, the operator must know the length of boom, theload radius, the boom angle, and if the lift is to beperformed over the side or over the rear.When performing lifts using the boom angleindicator that indicates an angle not noted on the loadchart, use the next lower boom angle noted on the loadchart for determining the capacity of the crane. Forexample, using the load charts in figure 12-47, the craneis rigged with 60 feet of boom, and the boom angleindicator indicates a boom angle of 57 degrees. A57-degree boom angle load capacity is not noted on theload chart, so you must use the next lower noted boomangle of 53 degrees for determining the capacity of thecrane.NOTE: Do not rely on the boom angle indicator forradius accuracy when lifts exceed 75 percent of the ratedcapacity. Measure the radius to avoid the possibility oferror.When using a radius measurement not noted on theload charts, use the next longer radius measurementnoted on the load chart for determining the capacity ofthe crane. For example, using the load charts in figure12-47, the crane is rigged with 50 feet of boom, and theradius measurement is 32 feet. A 32-foot radiusmeasurement is not noted on the load charts, so you mustuse the next longer radius measurement of 35 feet notedon the load chart for determining the capacity of thecrane.The number of part lines reeved on the main hoistblock can affect the capacity of the crane. If the craneis capable of being reeved with an eight-part line and thereeving is changed to a six-part line, the capacity of thecrane changes. On newer models of cranes, the capacityfor different parts of line configurations is noted on theload charts. On older models, you must refer to themanufacturer’s manual.The load chart provides the capacity of the cranewith outriggers set and without outriggers. “Outriggersset” means the outriggers are fully extended and theweight of the crane is off of the suspension system orthe tires are off the ground. If a situation arises wherethe outriggers cannot be fully extended, you must usethe without outriggers load capacity ratings.NOTE: Load capacities change when swingingfrom each quadrant of operation, such as from over therear to over the side.SAFE LIFTINGThe following factors are basic guidelines toperform safe daily crane operations:1. Determine the weight to be lifted and the cranerequired to make the lift safely.2. Travel the proposed route the crane will followto and from the project site, and complete the Crane LiftChecklist.3. Obtain the travel permits if required.4. Brief operators and riggers on the specifics ofthe lift and travel conditions.5. Inspect the crane area setup for stability and safeoperating area6. Fully extend the outriggers and use themaccording to the manufacturer’s instruction.7. Check the crane for levelness.8. Inspect all rigging hardware.9. Select the proper sling with sufficient capacityrating.10. Center the sling in the base (bowl) of the hookto avoid hook point loading, and ensure the hook blockis always placed over the center of the load to eliminateshock loading of the slings or cranes, resulting from loadshifts when a lift is made.11. Make ample safety allowances for unknownfactors.12. Stand clear of and do not walk under suspendedloads.13. Boom deflection.All crane booms havedeflection. When the load is lifted off the ground, theboom will deflect, causing the radius to increase.Increased radius may cause overloading of the crane.14. An uncontrolled swinging load can cause theradius to increase.15. Clean operating area. Water coolers, excesstools, grease, soda cans, and other unnecessary itemsshould be kept outside of the operating area of the crane.Water coolers must be kept off the crane to prevent12-32
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