There are many terms and definitions when it comes to the rigging and lifting industry, so we decided to break it down for you with a rigging glossary series—the ABC’s of rigging!
On our last glossary we listed some common rigging terms from A-C and ended with ‘crane’—today, let’s continue where we left off. There are many different types of cranes—(more than 10!)—so we decided to continue with those rigging terms.
Keep reading our glossary to discover rigging terms from Crane-D. Stay tuned to our blog page for our next series of rigging terms from D to E.
C—’Crane’
Read on to discover rigging terms that begin with ‘C’.
Crane (automatic): A crane that operates through a preset cycle(s) when it operates.
Bridge crane: A crane with a single or multiple-girder movable bridge that carries a movable trolley or fixed hoisting mechanism. It travels on an overhead fixed runway structure.
Crawler crane: A crane with rotating power plant structure, operating machinery and mounted base —it also has crawler treads for travel. This crane hoists, lowers and swings loads at various radii.
Double-girder crane: Has two bridge girders supported, in-between the end trucks.
Floor-operated crane: A power-operated crane controlled by an operator from the floor or walkway located in the crane-way. It uses power control switches or buttons on a pendant.
Gantry crane: A crane similar to an overhead bridge crane, except the bridge that carries the trolley is supported on two or more legs that run on fixed rails or another runway—usually 3 meters (10 feet) or more below the bottom of the bridge.
Jib crane: A fixed crane with a vertical rotating member supported at the bottom (some types have them on top), where an arm extends to carry the hoist trolley. Jib cranes are normally found on a vertical column as part of the jib crane or mounted on existing structures (ex. a wall-mounted jib crane).
Manually operated crane: A crane where the hoist mechanism is driven by pulling an endless chain, or whose travel mechanism is driven by manually moving the load.
Monorail crane: A crane or hoist attached to a trolley that runs on flanges of a structural beam.
Overhead crane: A crane with a single or multiple girder movable bridge, carrying a movable trolley or fixed hoisting mechanism, and traveling on an overhead fixed runway structure.
Power-operated crane: The mechanism is driven by electricity, air, hydraulic, or an internal combustion engine.
Remote-operated crane: A crane controlled by any method other than a pendant, rope, or attached cab.
Semi-gantry crane: Gantry cranes have one end of the bridge supported by leg(s) that run on a fixed rail or runway. The other end is supported by end trucks running on an elevated rail or runway.
Single-girder crane: A crane having one bridge girder mounted between the end trucks—it’s also supported from the end trucks.
Wall crane: A crane with a jib that’s supported from a side wall or line of columns of a building. It’s a traveling-type crane and operates on a runway attached to the side wall or line of columns.
Craneway: Area (length and width) served by crane.
Creep speed: A slow and constant fixed rate of motion of the hoist, trolley, or bridge. This is typically at 1 to 10% of the normal full-load speed.
Critical diameter: Diameter of the smallest bend for a given wire rope that allows wires and strands to adjust themselves by relative movement while remaining in normal position.
Critical load/lift: A load or lift that creates difficult conditions—this can range from a delay, to anything that compromises the safety and operations of a facility, high levels of hazardous materials to anything that causes injury or illness.
Critical service: The use of equipment or tackle for hoisting, rigging, or handling of critical items, or other items in, around, or above spaces containing critical items.
Crossover points: These are points where the rope contacts the previous rope layer when spooling multi-layer rope on a drum.
Cross rod: Wire used to join metal mesh spirals into a complete fabric.
Crow’s foot: A wedge socket type wire rope end termination.
Cylindrical drum: Hoisting drum with uniform diameter.
‘D’
Read on to discover rigging terms that begin with ‘D’.
D.C.: Direct current.
D/d Ratio: A term regarding wire rope. D = Diameter of curvature where rope is bent. d = diameter of rope.
Dead end: Point to fasten one rope in a running rope system. The other end is fastened at the rope drum.
Deadman: An object or structure that exists or is built to be used as an anchor for a guy rope.
Deceleration stress: Additional stress imposed by decreased load velocity.
Deflection: The point where a load member sags cause by imposed live or dead loads—typically measured at mid-span as the distance along a straight line between supports. It can also mean any deviation from a straight, horizontal line.
Derrick: A piece of equipment used to lift or lower loads. It’s made of a mast or equal member held at the head by braces or guys—it can be used with or without a boom, and is used with hoists and ropes.
Design Factor (sometimes referred to as safety factor): An industry term usually computed by dividing the catalog Breaking Strength by the catalog Working Load Limit and generally expressed as a ratio. For example: 4 to 1.
Diameter (wire rope): The measurement around the wire rope, space wire rope will contain.
Direct geared: A hoist with one or more drum geared directly to its power source.
Dog leg: Permanent short bend or kink in wire rope caused by improper use.
Dragline: Wire rope used to pull an excavating/drag bucket. It’s also used to express a particular type of
mobile crane that uses a drag bucket during excavation.
Drifting: Pulling a suspended load laterally to change its horizontal position.
Drift point: Point on a travel motion controller that releases brake while the motor isn’t energized. This allows you to coast before the brake is set.
Drive: An assembly that consists of motors, couplings, gear, and gear case(s) used to propel a bridge, trolley, or hoist.
Drive girder: Girder where bridge drive, cross shaft, walk, railing, and operator’s cab are mounted.
Drum: The diameter of a barrel of a cylinder drum or tapered, conical drum. This is where cable is wound for use or storage. The drum may also refer to the cylindrical member where rope is wound to lift or lower the load.
Drum capacity (rope): Length of a specific diameter of rope that can be wound on a drum.
Drum hoist: A mechanism that uses one or more rope drums. This is also called a hoist, winch, or hoisting engine.
Dynamic loading: Loads fed into the machine/components by moving forces.