Abstract: A load limiting device for a jib extension includes a pivotal insert adjacent the tip of the jib extension, a cable sheave mounted on the insert, a force measuring device for measuring forces imposed upon the insert by a load on the cable, an angle transducer for measuring the angle of orientation, and means for determining, based upon such force and angle of orientation, the load on the jib extension.

Abstract: This invention relates to the coating of steel parts with organic polymeric materials for resistance to corrosion, abrasion, impact, salt solutions of high and low pH (both in liquid as well as vapor state) and corrosive atmospheric gases under the environment of high relative humidity and ambient conditions of temperature and pressure. To obtain secure and permanent adhesion of the coating on the steel article a polymeric coating is formulated so as to achieve chemical grafting to the steel face. This involves the use of monomers, prepolymers, catalyst and a graft initiator system. The monomers are preferably polyfunctional and when applied onto a metallic substrate, react via graft polymerization with the metal to form a polymerized layer coated onto the surface of the steel substrate.

Abstract: A wire or cable is provided internally of an extensible boom to connect a switch, control or other element, such as an anti-two block switch, at one end of the extensible boom to elements or controls at the other end, such as controls for operating the crane. The wire or cable is itself inextensible, and is normally maintained taut. Wire control elements are provided to permit movement of the wire to accommodate extension and retraction of the telescopic boom sections. The wire internal to the extensible boom is fully protected from the environment and external hazards.

Abstract: A jib pin alignment jack assembly for aligning the apertures on the proximate end of a jib with apertures on the nose assembly of a boom section to facilitate the manual insertion of pins therein for holding the jib in the operative position relative to the boom section. A manually actuated hydraulic jack is mounted on the underside of the jib at the proximate end thereof, and the jack saddle is extendable to push against the nose assembly on the boom section, to thereby align the apertures for insertion of pins therein. One person is able to not only actuate the hydraulic jack to align the apertures but also insert the pin in the aligned apertures.