The 2000sqm facility houses two powered gantry cranes that are fitted with Verlinde Eurobloc VT hoists. These have a capacity for lifting 1.5 metric tonne loads.
The lifting technology has been employed at the base that services the Puma helicopters, which are medium lift capacity machines used by French military forces during both tactical and logistical transportation operations.
Measuring 14m in length and with rotor diameter of 15m, the Pumas can bear a live load of 1.5 metric tons at a cruising speed of 250 km/hr over a distance of 550 km.
Verlinde hoist technology has been adopted at one key operations hangar, which has recently been fully renovated. Central to this site are two Manulec gantry cranes that are fitted with the manufacturer’s Eurobloc VT hoists and lifting components.
According to Verlinde, the existing, prior to the renovation made use of mobile cranes that were "difficult to manipulate and whose loading arms had insufficient slew angle to ensure rapidity and facility of maintenance operations". In addition, the equipment also required frequent maintenance operations to ensure 24hr availability.
The Manulec and Verlinde equipment is integral to the 45m deep-covered hangar, which is divided into two identical spaces.
According to the company, this layout enables the simultaneous maintenance of four helicopters, which mostly involve the engines and mechanical, electrical and hydraulic parts.
Heavy machine parts to be shifted, which are located at the top of the helicopter’s fuselage, include two engines that each weighing 225kg as well as the main rotor system, which provides lift for the helicopter.
Elsewhere, the 418kg main rotor system combined with the main gearbox weigh a combined 720kg. This complex mechanical assembly is a key part of the machine as it provides the transfer of power to drive the blades as well as their pitch angle.
François Mathys, CEO at Manulec and a former air force officer and helicopter pilot commissioned the two unique and freestanding identical structures for the hangar.
The company said there were two important factors figured among the constraints. The first was that the building’s structure was unable to support the handling system and the second was that it was vital to be able to move from one workspace to the other without hindrance from obstacles on the floor. To meet these constraints, the main beam of the 23m long powered gantry crane is set on two 11m high legs.
"The specification for an obstacle-free central area meant that, to ensure gantry crane travel, a metal roller path was required anchored to the floor by countersunk flush head bolts," explained the company.
It added: "The gantry crane control system is offset to one side and is made up of an assembly of a rail fixed to the floor and metal wheels integral with the crane end carriage.
To prevent the gantry crane from twisting during travel, since the control system is on one side, the two legs are driven by the matched and synchronized motors with a variable speed drive system.
"The gantry crane main beam on which the hoist travels is also very specific. Its closed box section with a steel diaphragm welded inside, contributes to the rigidity of the assembly and to keeping the legs aligned."
With a rigid "girder-gantry crane" assembly design, Manulec defined the most uniform equipment possible in terms of efficacy, space requirements and weight.
With that in mind, the manufacturer opted for Verlinde Eurobloc VT1 type electric wire rope hoists with short headroom, which enable a load of 3.2 metric tons to be lifted to a height of 11m.
In this instance, the load limiter was calibrated to 1.5 metric tons classifying the hoist in frame structure FEM 3M (6 ISO). On the girder, the hoist travels a distance of 22m and has a lifting height of 11m, with hoisting or changing of an engine requires accurate load positioning. The Eurobloc VT, owing to its design, offers limited lateral travel of the hook block when lifting to help keep the load aligned, while the variable speed system on all travelling motors for lifting, travel or long travel prevents load rocking.
