change when rotating a load from one quadrant toanother. This information is provided on the crane loadchart.LATTICE BOOM CRANEThe major components of a lattice boom crane areshown in figure 12-11.Inspecting each of thesecomponents is part of the operator’s prestart inspection.The lattice boom supports the working load and isthe most common boom used in the NCF. It is used onall types and makes of cranes and is mounted at the boombutt on the revolving superstructure. The basic boomconsists of the boom butt and boom tip, and the lengthis increased by adding boom extensions.Boom SectionsLattice boom sections are made of lightweight, thinwall, high strength alloy tubular or angle steel and aredesigned to take compression loads. The most commonboom is tubular. Terminology of a lattice boom sectionis shown in figure 12-12.Manufacturers have set a zero tolerance on rust,bent lacings or cords, cracked welds, and other problemsthat affect the strength of the lattice boom. This zerotolerance requires crane crews to use extreme care whenhandling unused sections with forklifts, storing unusedsections away from traffic areas, transporting andsecuring sections on tractor-trailers, and preventingequipment or obstacles from running into the boomwhile mounted on the crane during transport,performing operations, or when parked.As outlined in the Management of Weight-HandlingEquipment, Maintenance and Certification, NAVFACP-307, all lattice boom cranes with structural damage tothe main cords of the boom must be immediatelyFigure 12-11.—Lattice boom crane components.12-6
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business