Definitions Flashcards
A/D Director
individual who meets the subpart’s requirements for an A/D Director, irrespective of the person’s formal job title or whether the person is non-management or management personnel.
Assembly/Disassembly
“Erecting and climbing” / “dismantling”. Regardless of whether the crane is initially erected to its full height or is climbed in stages, the process of increasing the height of the crane is an erection process.
Assist crane
Crane used to assist in the erecting and dismantling of a tower crane.
Audible signal
Made by a distinct sound or series of sounds. Examples include but not limited to sounds made by a bell, horn, or whistle.
Ballast
Weight added to a crane base to create additional stability; it does not rotate when the crane swings.
Base, anchor bolt
Crane base that is bolted to a footing.
Base, expendable
For static-mounted cranes, a style of bottom tower section or member that is cast into a concrete footing block; all or part of this component is lost to future installations.
Base, fixed ballasted
Crane base that is a ballasted platform that does not travel.
Base, knee-braced
Crane base that uses diagonal members to spread the loading.
Base tower
A mounting accessory to secure the bottom of the tower to a foundation, structural support, travel, or ballasted base.
Base, traveling
Crane base that is a ballasted platform mounted on bogies that ride along rails.
Blocking (cribbing)
Wood or other material used to support equipment or a component and distribute loads to the ground. It is typically used to support lattice boom sections during erection and dismantling and under outrigger and stabilizer floats.
Bogie
Assembly of two or more axles arranged to permit both vertical wheel displacement and an equalization of loading on the wheels.
Brace, tower
Structural attachment placed between a crane tower and an adjacent structure to pass loads to the adjacent structure and permit the crane to be erected to greater than freestanding height.
Buffer
Energy absorbing device for reducing impact when a moving crane or trolley reaches the end of its permitted travel.
Center of gravity
The point in the object around which its weight is evenly distributed.
Climbing
For freestanding, braced, or guyed cranes, the process whereby the height of the tower is increased by adding sections at the top; for internal climbing cranes, the process whereby the entire crane is raised or lowered on or within a structure which is under construction.
Climbing cross-member
Structural member attached to the end of the hydraulic cylinder used to engage the climbing ladders or lugs via pawls to raise or lower the crane structure.
Climbing frame
For freestanding, braced, or guyed cranes, a structural frame supporting the superstructure which surrounds the tower and contains arrangements to raise the frame and superstructure of the crane for insertion of an additional tower section; for internal climbing cranes, a frame used to transmit operational and climbing reactions to the host building frame.
Climbing ladder
Steel member with crossbars (used in pairs) suspended from a climbing frame and used as jacking support points when some cranes climb.
Counterjib
Horizontal member of a crane on which the counterweights and usually the hoisting machinery are mounted.
Crossover points
Locations on a wire rope which is spooled on a drum where one layer of rope climbs up on and crossed over the previous layer. This takes place at each flange of the drum as the rope is spooled onto the drum, reaches the flange, and begins to wrap back in the opposite direction.
Freestanding height
Height of a crane which is supported by the tower alone without assistance from braces, guys, or other means.
Gage, track
Horizontal distance between two rails, measured perpendicular to the direction of travel.
