This research is put forward because the tradition spiral rope slot reel can not satisfy several layers of real needs winding up in the big lift and heavy load hoist, and the design and development of reel product are grown to put forward period.
This paper introduces an optimum calculating method of hoisting drum diameter for bridge and gantry cranes. When the rope windes on drum multiple layers, so can be avoided t0 adopt a very big drum, reduced the weight of crane efficiently.
In the coiling of the wireline on a drum, there exists a certain deviation angle, i.e. the angle between the wireline axle and the vertical surface of the drum shaft, and this angle shouldn't be too large. This article works out the equations for calculating the allowable angle of the fast line leaving or closing the bight(shown as γ1 andγ2 in figure 1 in the article).