A survey by the UK’s Builders Merchants Federation three years ago highlighted safety problems with the use of truck loader cranes: the two main areas of concern were the insecure stowing of stabiliser legs and overheight booms hitting bridges when passing underneath.

One of the outcomes was the Association of Lorry Loader Manufacturers & Importers code of practice, published earlier this year (New guidance published… Apr99, p7).

Another was an initiative by Hiab to produce a demonstration vehicle to show its customers what technology is actually available, if they are prepared to pay for it. A 10tm-rated Hiab 102 loader has been fitted to a Volvo FM7 chassis with a 17t gross weight; the unit is aimed directly at builders’ merchants whose daily multi-drop deliveries place particular strains on both equipment and operators.

“By moving to computer-based crane control systems, we have been able to implement new safety devices, to make crane operation and transportation much safer for the operator and other road users,” says Hiab national accounts manager Geoff Hudson.

Hiab has installed a leg interlock system on its demonstrator, which comes into action if the stabiliser legs and leg beams are not securely stowed. An initial audible and visual warning system in the cab is used to alert the driver of the problem and this can be linked to the vehicle’s parking brake, keeping the brakes applied until the leg beams have been correctly and securely stowed.

Additionally, yellow warning lights are fitted on the end of each of the stabiliser legs, which flash automatically when the vehicle’s PTO system is engaged.

A similar warning system is employed for overheight situations, when the crane’s boom has not been fully folded away into its safe transport position. Like the leg stowage system, an overheight boom position triggers audible and visual in-cab warnings, along with the inability to release the parking brake until the crane is lowered to a safe transport height.

Additional safety options fitted to the demonstrator include a traffic-light style three-colour visual warning light system for the crane’s overload protection system and pressure sensors fitted to the operating platform.

For standard lifting operations, the warning light system maintains a constant green light. This changes to show amber when 90% of maximum lifting capacity is reached, then switches to red and prevents any further crane movements which would increase the lift. It is a system which can also be linked to an audible warning.

Platform sensing linked to inner and outer boom sensors prevents the crane from being slewed over the operator’s head, when there exists a danger that the operator may be struck by the crane, while the warning light system, visible through 360O, informs the operator when an overload situation occurs.

This technology is not unique to Hiab; Autogru PM, for example, had a similar feature on its new Series 12S model displayed at the Samoter exhibition in Verona, Italy in March.

Hiab’s demonstration vehicle was put on the road six months ago and since then has spent a week at a time in the hands of various customers. Hudson says that there are actually more features on this unit than any single customer would actually want. But having tried it out, the customers are in a better position to know what they should specify.

“It has had an impact,” says Hudson. “People have changed their specifications as a result of using this demonstration vehicle.” One such is a Norwich-based company, Trott Rentals, which principally hires to customers in civil engineering, construction and the builders’ merchant market. Trott Rentals’ new Hiab 102 is the first Hiab loader in the UK to be fitted with the “intelligent” stand-up controls.