Delivering greater lifting capacity, more profit, less environmental impact

Hiab's latest generation loader crane control system sets new industry benchmarks by not only increasing lifting capacity and cost efficiency but also by cutting fuel use to lessen environmental impact.

Delivering payload (or rated load) increases of up to 20 per cent and potential 40 per cent reductions in diesel oil use, Hiab's new loader crane control system was designed to meet customer needs for light cranes able to deliver the highest possible lifting capacity.

"What's remarkable is that such operator benefits as greater capacity and lower fuel costs don't just boost their profitability, but also makes a real contribution to curbing climate change," says Lars Andersson, R&D Manager Structure Mechanic Hiab Loader Cranes.

According to Lars Andersson, replacing the standard fixed displacement pump with a variable displacement pump in a truck with a HIAB XS 288 HiPro crane that uses about 7,000 litres of diesel oil per year would result in a 32-per cent fuel saving, or 2,200 litres. The savings would be even higher in an 800 HiPro crane using 10,000 litres per year with a 4,000-litre reduction.

"The greenhouse gas emissions of an 800 HiPro with a variable pump are ten tonnes less per year than with a fixed pump. Ten tonnes is the annual amount of carbon dioxide emissions of four cars," says Lars Andersson.

Although all Hiab HiPro series cranes have a load-sensing control system, just 15-20 per cent of them are currently equipped with a variable pump. Andersson says the reason is that people are more familiar with fixed pumps, and many are not aware of the savings a variable pump can bring.

Installing a variable pump into a new Hiab crane or retrofitting does require an investment of EUR 1,000-2,000. However, Andersson says the investment soon pays for itself.

"If the price of a litre of diesel oil is around one euro, in a 288 HiPro crane a variable pump would pay for itself in less than 18 months and in the 800 HiPro in just half a year. After that, the annual savings with the smaller crane would be EUR 2,200 and as much as EUR 4,000 with the bigger one," says Lars Andersson.

There are other major benefits too thanks to the ability of the variable pump to keep the oil temperature significantly lower, which means the hydraulic system remains at least 20 degrees Celsius cooler.

"In most cases there is not even a need to install an oil cooler, while the seals, hoses and other parts last longer due to the cooler temperatures," Andersson adds.

A crane needs energy in order to lift a load and to overcome frictional forces. Most loader cranes today have a pump that pumps a fixed flow of oil – in practice, a large part of the oil circulates directly back into the tank through a pressure relief valve.

If a customer chooses a fixed pump for a 166 HiPro crane, Hiab recommends a flow of 70-90 litres of oil per minute. To produce this amount of energy, the truck's diesel engine uses three litres of oil per hour. However, often the crane is turned only 90 degrees – from the loading dock to the truck's bed and back – and with 60-per cent speed.

"This function uses only 25 litres of oil per minute, so at least 50 litres of oil is circulating in the system in vain. The excess energy converts to heat in the control system, and since the oil temperature must be kept below 70 degrees, an oil cooler is needed," says Lars Andersson.

The simplest of the control systems are used in the Hiab Classic series of cranes: a manually-controlled, open V80H control valve and a basic safety system SPACE 3000 that is compliant with latest EU criteria.

Hiab's more advanced Duo cranes have the same steel structure and control system as the Classic cranes, but their safety system recognises the kind of work the crane is doing at any given time and, depending on the work, the lifting capacity can be increased by ten per cent.

The HiDuo version also shares the same steel structure, but uses a remotely controlled V80R control valve and an integrated SPACE 4000 safety system. And HiPro cranes have an advanced load-sensing V91M valve and integrated SPACE 5000 safety system.

"The HiPro crane's rated load can be increased by up to 25 per cent, or even more on long outreaches, leading to enhanced productivity thanks to the load-sensing control system and Pump Flow Distribution," notes Lars Andersson.

Andersson adds: "The result of dedicated ongoing research and development for over two decades, Hiab's crane control systems today manually or automatically control the cranes' lifting capacity for enhanced performance, safety and operator comfort. Our new generation loader crane control system raises the bar dramatically by not only increasing lifting capacity and cost efficiency, but also by lessening environmental impact by reducing fuel use."

The Hiab Group is the world's leading supplier of on-road load handling equipment. The product range includes HIAB loader cranes, LOGLIFT and JONSERED forestry and recycling cranes, MULTILIFT demountables, ZEPRO, FOCOLIFT, AMA and WALTCO tail lifts, as well as MOFFETT and PRINCETON PIGGY BACK® truck-mounted forklifts. In 2006 Hiab's net sales totalled EUR 914 million, it delivered over 60,000 load handling units and employed 4,400 people. Hiab is part of Cargotec Corporation, the world's leading provider of cargo handling solutions.

www.hiab.com