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A rigger or slinger is a skilled tradesperson who specializes in the assistance of manual mechanical advantage device comprising pulley, block and tackle or motorised such as a crane or derrick or chain hoists (chain fall) or capstan winch.
The term comes from the days of sailing ships, when a digger was a person who worked with rigging, that is, ropes for hoisting the sails. Sailors could put their rope skills to work in lifting and hauling. In an era before mechanical haulage and cranes, ropes, pulleys and muscle power were all that was available to move heavy objects. A specialized subset are telecommunication riggers, entertainment industry riggers. In time, rigging became a trade in itself, giving rise to modern usages with some original terminology remaining, with its roots all but forgotten.
Riggers attach loads of equipment to cranes or structures using shackles, cables, chains, clamps or straps, employing pulleys, winches, lifts or chain hoists (aka chain motors). Quick load calculations are necessary for each load and engineering principles are always in play. Riggers use various suspension techniques to get their load around obstacles on a construction site or loading dock or event site to the desired location and height. [1]
A winch is a mechanical device that is used to pull in or let out or otherwise adjust the tension of a rope or wire rope.
A block and tackle or only tackle is a system of two or more pulleys with a rope or cable threaded between them, usually used to lift heavy loads.
A crane is a type of machine, generally equipped with a hoist rope, wire ropes or chains, and sheaves, that can be used both to lift and lower materials and to move them horizontally. It is mainly used for lifting heavy objects and transporting them to other places. The device uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human. Cranes are commonly employed in transportation for the loading and unloading of freight, in construction for the movement of materials, and in manufacturing for the assembling of heavy equipment.
A rope is a group of yarns, plies, fibres, or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than similarly constructed cord, string, and twine.
A derrick is a lifting device composed at minimum of one guyed mast, as in a gin pole, which may be articulated over a load by adjusting its guys. Most derricks have at least two components, either a guyed mast or self-supporting tower, and a boom hinged at its base to provide articulation, as in a stiffleg derrick. The most basic type of derrick is controlled by three or four lines connected to the top of the mast, which allow it both to move laterally and cant up and down. To lift a load, a separate line runs up and over the mast with a hook on its free end, as with a crane.
A fly system, or theatrical rigging system, is a system of ropes, blocks (pulleys), counterweights and related devices within a theater that enables a stage crew to fly (hoist) quickly, quietly and safely components such as curtains, lights, scenery, stage effects and, sometimes, people. Systems are typically designed to fly components between clear view of the audience and out of view, into the large opening, known as the fly loft, above the stage.
Wire rope is several strands of metal wire twisted into a helix forming a composite rope, in a pattern known as laid rope. Larger diameter wire rope consists of multiple strands of such laid rope in a pattern known as cable laid.
A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium. The most familiar form is an elevator, the car of which is raised and lowered by a hoist mechanism. Most hoists couple to their loads using a lifting hook. Today, there are a few governing bodies for the North American overhead hoist industry which include the Hoist Manufactures Institute, ASME, and the Occupational Safety and Health Administration. HMI is a product counsel of the Material Handling Industry of America consisting of hoist manufacturers promoting safe use of their products.
A chain is a serial assembly of connected pieces, called links, typically made of metal, with an overall character similar to that of a rope in that it is flexible and curved in compression but linear, rigid, and load-bearing in tension. A chain may consist of two or more links. Chains can be classified by their design, which can be dictated by their use:
Shear legs, also known as sheers, shears, or sheer legs, are a form of two-legged lifting device. Shear legs may be permanent, formed of a solid A-frame and supports, as commonly seen on land and the floating sheerleg, or temporary, as aboard a vessel lacking a fixed crane or derrick.
A rigger is one who works on ropes, booms, lifts, hoists and the like for a stage production, film, or television show.
A bulk-handlingcrane is one that, instead of a simple hook that can handle a range of slung loads, has an integral grab for lifting bulk cargoes such as coal, mineral ore etc.
A differential pulley —also called "Weston differential pulley", sometimes "differential hoist", "chain hoist", or colloquially "chain fall"— is used to manually lift very heavy objects like car engines. It is operated by pulling upon the slack section of a continuous chain that wraps around two pulleys on a common shaft. The relative sizing of the two connected pulleys determines the maximum weight that can be lifted by hand. If the pulley radii are close enough, then the load will remain in place until the chain is pulled.
A drawworks is the primary hoisting machinery component of a rotary drilling rig. Its main function is to provide a means of raising and lowering the traveling block. The wire-rope drill line winds on the drawworks drum and over the crown block to the traveling block, allowing the drill string to be moved up and down as the drum turns. The segment of drill line from the drawworks to the crown block is called the "fast line". The drill line then enters the first sheave of the crown block and makes typically 6 to 12 passes between the crown block and traveling block pulleys for mechanical advantage. The line then exits the last sheave on the crown block and is fastened to a derrick leg on the other side of the rig floor. This section of drill line is called the "dead line."
A treadwheel crane is a wooden, human powered hoisting and lowering device. It was primarily used during the Roman period and the Middle Ages in the building of castles and cathedrals. The often heavy charge is lifted as the individual inside the treadwheel crane walks. The rope attached to a pulley is turned onto a spindle by the rotation of the wheel thus allowing the device to hoist or lower the affixed pallet.
Rigging in entertainment can be broken down into two main subjects – theatrical rigging and arena-style rigging. All the same skills apply in both genres. The first takes place in a theatre, and typically involves the theatre's permanent fly system. The other in an arena or "exposed structure venue" such as a convention center, ballroom, warehouse etc.
Wire rope spooling technology is the technology to prevent wire rope getting snagged when spooled, especially in multiple layers on a drum.
Rigging is both a noun, the equipment, and verb, the action of designing and installing the equipment, in the preparation to move objects. A team of riggers design and install the lifting or rolling equipment needed to raise, roll, slide or lift objects such as with a crane, hoist or block and tackle.
The Leap Cane Lift is a heritage-listed piece of agricultural equipment at Bruce Highway, The Leap, Mackay Region, Queensland, Australia. It was built before the 1960s. It was added to the Queensland Heritage Register on 5 February 2010.
A hydraulic jigger is a hydraulically-powered mechanical winch.