The jib cranes, with manual or electrical rotation, in column-or wall-mounted models, are designed to handle goods inside a plant, in a yard or next to processing machinery.
The jib cranes have three functions:
- Lifting a load vertically using the hook of the lifting unit, generally consisting of a chain hoist;
- Travelling of the load with the help of a hoist-carrying trolley, electric or manual, which run along the jib of the crane (with the exclusion of the crane with an articulated jib where the hoist normally does not run with the trolley because the hoist is fixed at the jib end);
- Rotating the load, around the constraint axis, using a manual push action on the load itself or electrically by means of a motor reducer, covering the circular area underneath it, bound by the rotation range of the jib.
Key parameters to be observed when choosing the jib crane are:
- Functional dimensions: height of the arm, which determines the hook run of the hoist, and its jump (jib) must be selected so as to guarantee the functional coverage of the area to be served in consideration of the surrounding encumbrances.
- Capacity: This is determined by the heaviest load to be lifted.
- Type of movement: manual or electric in relation to the characteristic of the mass to handle and the type of arm already selected (Channel profile jib – underbraced – overbraced – articulated).
- Nature of the load: delicate or not determines by its positioning the choice of the most suitable speeds of handling (lifting and moving). In some cases two speeds hoists can be used, with slow positioning speed.
- Area of use: the jib craned can be used inside and/or in a covered area, sheltered from bad weather and wind.
In case of use outside measures must be taken in relation to the surface treatment (sandblasting – painting) as well as a system of stopping brake and an adequate protection covers.