Heavy lifting

Chris Lindley-Smith discusses the growing demand for more efficient cranes and how new technology is improving safety and productivity

From workshops and manufacturing plants through to railways and bridges, overhead cranes play a key role in boosting efficiency across a broad range of industries in both the private and public sector.

Factory expansions, investments in infrastructure and an overarching need to make operations more productive, means that the demand for overhead cranes remain high both in the UK and across the globe.

Speed, efficiency and safety also remain top priorities for the end user, which means crane manufacturers must invest in research and development to ensure their products keep up with the pace of UK industry.

Driving down costs
Contractors and engineers who need to source overhead cranes can now benefit from more standardised products, which have been designed to reduce costs but maintain performance levels. Variable Frequency Drive (VFD) technology for example now comes as standard on many crane systems.

VFD drives provide a fully programmable solution allowing the end user to adjust crane speeds to suit the application. Controlled acceleration and deceleration times minimise load swing compared with traditional two speed drives. VFDs can also be integrated with Street Crane’s anti-sway software providing a high level of load control and virtually eliminating load swing.

Standardising products also means that cranes can now be manufactured and delivered far quicker than ever before. It is now possible to make and deliver a bespoke crane from scratch in just four weeks – ten years ago this would have been unheard of, but in today’s fast moving world this is a common requirement.

Improving safety and efficiency
However, demand isn’t just driven by price and delivery. Safety and efficiency are paramount and these requirements are resulting in new mechanical and technological developments.

These include advanced wire rope hoists, which 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.

Where multiple cranes are used in the same bay, anti-collision and proximity limit switch systems are frequently installed.

Crane radio remote 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.

Smart technology and semi-automation
Furthermore, advances in technology are leading to new equipment that prevents any dangerous lifting, including side pulling which is one of the biggest misuses of cranes. If an operator tries to lift a load and the hook is at an angle, then the load will swing. New technology is now available that stops the hoist operating if it detects that the hook or load isn’t purely vertical.

The use of semi-automation is also on the up. Although automatic storage and retrieval has existed for some time, customers are starting to ask for semi-automatic applications on standard cranes. This technology enables the crane to automatically travel to the right area before the operator lowers it under manual control.

Safe working periods
Companies are also seeking more information about how their crane is being used in line with the latest health and safety legislation, which requires operators to know that a crane is being operated within its safe working period.

This is driving demand for Safe Working Period (SWP) monitors with people now asking us to fit these as standard. These monitors log data about the cranes use and calculate how much operational time is left before it should be overhauled or replaced based on its duty rating. This avoids crane overuse, which affects the mechanisms and structures, making the system less reliable as well as potentially unsafe.

Continuous improvement
Production facilities, warehouses and infrastructure projects will always benefit from overhead cranes but crane manufacturers must continuously improve to ensure their products meet changing demands and pressure to both build and operate faster.

From the development of low maintenance hoists through to smart technology features, crane manufacturers have a vital role to play in improving both the efficiency and safety of operations no matter what size they are or which industry they’re serving.

Case study
Cutting-edge factory benefits from Street’s bespoke ‘doughnut’ crane
Located in Sheffield, AMRC Factory 2050 is the UK’s first reconfigurable assembly and component manufacturing facility for collaborative research. The £43m 7,000 sq m circular facility is constructed largely from glass to showcase the advanced manufacturing technologies of the AMRC with Boeing’s Integrated Manufacturing Group.

AMRC required reliable and efficient overhead cranes, which would be in constant use, locating, moving and positioning heavier objects such as robots and machine beds. One of the key challenges was to source a crane that could operate effectively around the circular building.

Main contractor Interserve turned to Street to design, manufacture and install a bespoke, circular overhead crane capable of lifting products weighing up to five tonnes. This single girder crane incorporates bespoke end carriages that enable it to travel around the curved track of the circular building.

Two 10-tonne cranes were also supplied and installed. These can operate in tandem ensuring more stability, which is essential for lifting objects such as flexible aircraft wings.

Ben Morgan, head of the Integrated Manufacturing Group/ Factory 2050 said: “Street’s overhead cranes form an essential part of the facility as they are in constant use, locating, moving and positioning heavier objects such as robots and machine beds.

“We needed a lighter crane for the circular building and given its iconic shape, turned to Street to engineer a product that matched our exact specification. The larger cranes are used in tandem to help improve safety. Aircraft wings for example can be flexible, so lifting them with two cranes ensures more stability.”

Chris Lindley-Smith, Sales Director at Street added: “The circular, single girder crane is unlike any other we’ve manufactured before as it incorporates special end carriages that enable it to travel around the track of the circular building. All the cranes have been fitted with our renowned ZX hoists, which will maximise reliability, production and performance, and minimise maintenance requirements.

“To improve safety, remote radio controls have been installed which allow the crane operator to select the position that gives the best view for lifting, moving and load placement.”

Chris Lindley-Smith is Sales Director at Street Crane. Established 70 years ago, Street Crane is the UK’s largest crane and hoist manufacturer. Its main manufacturing activities are centred in Chapel-en-le-Frith and include a £3 million hoist assembly plant, which opened in 2014. The company is a major exporter, supplying crane kit and component products overseas via a global network of nearly 90 overseas distributors in 48 countries.

For more information, please see www.streetcrane.co.uk