Search results
Results from the WOW.Com Content Network
Usually jib arms are attached to a vertical mast or tower or sometimes to an inclined boom. In other jib-less designs such as derricks, the load is hung directly from a boom which is often anomalously called a jib. A camera jib or jib arm in cinematography is a small crane that holds nothing but the camera. [4]
A level-luffing crane is a crane mechanism where the hook remains at the same level while luffing: moving the jib up and down, so as to move the hook inwards and outwards relative to the base. [ 1 ] Usually the description is only applied to those with a luffing jib that have some additional mechanism applied to keep the hook level when luffing.
A jib crane is a type of crane - not to be confused with a crane rigged with a jib to extend its main boom - where a horizontal member (jib or boom), supporting a moveable hoist, is fixed to a wall or to a floor-mounted pillar. Jib cranes are used in industrial premises and on military vehicles.
By February 11, 2009, the tower was 105 feet (32 m) above street level. [26] On July 2, 2009, over 1,200 cubic yards (920 m 3 ) of concrete were poured to form parts of the street-level plaza. On August 13, the builders of 1 WTC set a 70 short tons (64,000 kilograms) piece of steel into place—the largest column installed yet at the building.
Crane The tower crane (see picture) is a modern form of balance crane that is fixed to the ground. A horizontal boom is balanced asymmetrically across the top of the tower. The long arm carries the lifting gear. The short arm is called the machinery arm; this holds the motors and electronics to operate the crane, as well as the concrete ...
The jib has a radius (reach) of 35 feet (11 m) and a height of 40 feet (12 m). The crane weighs 120 tons. A vertical boiler inside the cab operates at 100 psi and supplies two twin-cylinder steam engines: one for slewing (turning) the crane, a larger one for winding the lifting chain.
The Manitowoc Company, Inc. is an American manufacturer which produces cranes and previously produced commercial refrigeration and marine equipment. It was founded in 1902 and, through its wholly owned subsidiaries, designs, manufactures, markets, and supports mobile telescopic cranes, tower cranes, lattice-boom crawler cranes, and boom trucks under the Grove, Manitowoc, National Crane, Potain ...
On March 15, 2008, a crane owned by New York Crane & Equipment collapsed during construction. Seven people were killed and 24 others were injured. [ 5 ] It was a luffing-jib tower crane manufactured by Favco that was 200 feet (61 m) tall at the time of the collapse.