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A hoist controller is the controller for a hoist. The term is used primarily in the context of electrically operated hoists, but it is apparent that the control systems of many 20th century steam hoists also incorporated controllers of significant complexity. Consider the control system of the Quincy Mine No. 2 Hoist. [1]
Hoist atop an elevator. 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.
A drum hoist (steel wire rope visible) and motor. In underground mining a hoist or winder [1] is used to raise and lower conveyances within the mine shaft.Modern hoists are normally powered using electric motors, historically with direct current drives utilizing Ward Leonard control machines and later solid-state converters (), although modern large hoists use alternating current drives that ...
Such systems operate between 4,000 to 5,800 psi (28,000 to 40,000 kPa). The North American market developed low pressure / high volume systems, which allowed operators to share the hoist's hydraulic system with other hydraulically powered devices. These systems typically operate with a larger gear pump and larger hydraulic reservoir. Operating ...
A punch down tool, punchdown tool, IDC tool, or a Krone tool (named after the Krone LSA-PLUS connector), is a small hand tool used by telecommunication and network technicians. It is used for inserting wire into insulation-displacement connectors on punch down blocks , patch panels , keystone modules , and surface mount boxes (also known as ...
Headframe of the #1 Shaft at Oyuu Tolgoi. A steel headframe is less expensive than a concrete headframe; the tallest steel headframe measures 87 m. [4] Steel headframes are more adaptable to modifications (making any construction errors easier to remedy), and are considerably lighter, requiring less substantial foundations.
A similar heavy-duty unit with a combination chain and cable became available in 1935 that was used by railroads, but lacked the success of the cable-only type units. [1] A similar tool to a come-along is a cable puller, which does not have a drum and ratchet but directly grips the cable, allowing unlimited lengths of wire rope to be used.
A gin pole used to install a weather vane atop the 200-foot steeple of a church Roof trusses being assembled with gin poles. The gin pole is derived from a gyn, and considered a form of derrick, called a standing derrick or pole derrick, [2] distinguished from sheers (or shear legs) by having a single boom rather than a two-legged one.