Selecting the right crane systems to boost productivity
No matter how small or large an operation, selecting the right cranes and hoists plays a vital role in boosting productivity.
Increasing competition, lean manufacturing and changing consumer demands are just some of the challenges which are driving the need for more effective crane systems. Specified correctly, cranes and hoists can have a major impact on the efficiency of an operation, ensuring businesses stay one step ahead of the competition. Chris Lindley-Smith, sales director at Street Crane
Cranes and hoists have been used for decades, but advances in technology have seen their design change significantly.
Street wire rope hoists for example, have been designed to work regularly and reliably with minimal downtime for scheduled maintenance. These feature fully enclosed hoist and travel transmissions with oil-bath lubricated gears and gearbox braking as standard. Compared with open gearbox systems, these are less likely to suffer any advanced wear and tear no matter how intense the operating environment.
Hoist travel systems are also available with heavy duty long-life guide rollers, therefore removing the need for traditional wheel flanges and reducing rolling resistance and wheel and bridge wear as well as radically improving trolley control and stability.
Crane duty ratings
As well as considering new design technology, there are a number of key factors to consider when choosing a crane. Crane usage is the most important to define how heavily the crane will be used throughout its working life. Crane overuse means reduced life and reliability, so must be avoided to ensure an operation remains as safe and productive as possible.
Known as the crane duty rating, information about the daily number of lifting cycles and proportional loadings is used to establish what crane mechanisms and structures are required for the crane to operate reliably and safely for a specific length of time. Different duty ratings can affect the selection of all transmission components, wheels, hooks, wire rope and structural elements so it is essential that these are fully understood.
Facilities and applications
The type of facility also needs to be taken into account. For larger buildings where a clear floor space is critical, an underslung crane will be most appropriate as this can run on tracks which form part of the roof structure. This design eliminates the need for runway columns so the cranes can be suspended in the centre of large assembly areas without restricting access or work flow on the factory floor.
For smaller spaces which can’t support heavy crane loads, crane systems can be free standing on existing floor surfaces or prepared foundations, allowing high performance crane systems to be installed completely independently of any existing building structure.
If large and small-scale lifting is required, this will also affect the design of the lifting system. Large overhead crane operation should be integrated with smaller lifting systems for workstation use. This helps improve efficiency as avoids operators waiting for lifting equipment to become available.
Some very demanding industry applications require heavy duty equipment such as Street’s VX range for high capacity lifts, continuous processes, large hoisting distances and high speeds.
Every production process is different so operators must also ensure that the crane system is manufactured to meet their individual requirements. It is worth consulting with the crane manufacturer to discuss how to customise and accessorise the crane to meet all process requirements. From simple load spreading beams through to the use of bespoke handling equipment including features such as multiple lifting hooks, rotating hooks and multispan structures, there is a wide range of options available.
Another key requirement of an overhead crane is improving safety, which in turn helps to minimise downtime and improve performance. Whether the lifting capacity is 5 or 50 tonnes, it is essential that there are measures in place to minimise risks for the operator.
For larger lifts when multiple cranes are used in the same bay, anti-collision and proximity limit switch systems should be installed. Crane remote radio controls are also becoming very popular as they enhance safety by allowing the crane operator to select the position that gives the best view for lifting, moving and load placement.
As factories continue to evolve in line with the changing marketplace, so does crane and hoist technology. By working in partnership with crane manufacturers, organisations of all sizes can not only benefit from this new technology, but expert advice that ensures their operation is as productive as possible both now and in the future.
This article first appeared in the May issue of Handling & Storage Solutions (HSS)