Cranes can boost work efficiency and reduce costs

Cranes are used to handle loads within a limited operating area, with lifting and lowering as the main functions. Cranes, which are materials handling equipment, are classified with regard to the emphasis placed on various functions and special criteria. Typical cranes are:

• overhead travelling cranes,
• gantry cranes,
• cantilever cranes,
• slewing cranes,
• special (e.g. heavy lift crane).

 

 

Overhead cranes

They are used as indoor cranes in workshops (shop crane), warehouses, power plants, rolling mills, foundries, engine rooms, ironworks, production plants, etc. Overhead travelling cranes travel on overhead runways, leaving the floor free for other handling and work. The operating area of travelling cranes is rectangular, ideally equalling the workshop surface. Overhead cranes can be operated from a cab located on the bridge or trolley, or remote-controlled. Depending on the load capacity of the crane, room and span, overhead cranes can have a single, double or four girder design.

 

 

Gantry cranes

Gantry cranes have a portal, an empty space straddled by the gantry (portal cranes). They are used to handle general cargo and bulk material in warehouses, logistics terminal, etc. Unlike overhead cranes, gantry cranes have an elongated bridge over the supports so that we get unilateral or bilateral cantilevers. Gantry cranes have a fixed and a hinged post. The construction is statically determinate. We also cooperate in the development of the latest designs of oval girders, which result in savings, as they are easier to manufacture, are more aerodynamic, do not require additional reinforcements against buckling, the crane requires less energy and the reduced mass reduces wheel pressure, which favourably affects the lifespan of running wheels and the runway.

 

 

Lifting equipment

The capacity of materials handling equipment depends on operating speed and the time required to lift and lower a load. This time is often longer than the operating time of the crane. Lifting equipment has to enable fast and safe lifting and lowering of load. If the materials handling equipment is planned to handle different loads, it needs a universal lifting device and if it handles the same load, the device is adapted to the load type.

It has to be handy, light and require as few service personnel as possible. It has to enable fast and simple operations, be break-resistant and designed so as to prevent dislodging of load. A universal lifting device is the hook.

 

The following is used to handle general cargo:
- chains and ropes,
- carriers:
- simple carriers (for carrying long, wide, extensive loads), e.g. section steel, long shafts, casts, pipes, sheet metal, cauldrons, etc.
- spreaders
- tongs (for handling moulds, ingots, etc.),
- grippers (for sheet metal, etc.),
- platforms (for the handling of several pieces of general cargo, etc.),
- pallets,
- containers, etc.

The following is used to handle bulk material:
- bulk material containers (for coal, ore, grain, gravel, sand, etc.),
- crane ladles,
- drop bottom skips,
- grabbers, etc.

Special materials handling equipment:
- load lifting magnets (for ferromagnetic materials – steel blocks, section steel, rails, sheet metal, scrap iron, etc.),
- vacuum lifters (for sheets of non-magnetic steel, copper, aluminium, marble, artificial stone, glass, plastic materials, concrete and other materials with a smooth and non-porous surface).

 

 

NOKRAN INŽENIRING d.o.o. – designing of materials handling equipment

As a mechanical design and engineering company, we design all types of cranes for general cargo and bulk material handling. We have been designing materials handling equipment, which is exposed to dynamic loads, for over 30 years and have extensive references.