Crawler cranes with telescopic booms are comparatively rare machines. SpanDeck of the USA offers the four-model Mantis range and has found a niche market for which Favelle Favco Cranes (USA) is also now gunning. Sennebogen of Germany and Terex Bendini in Italy also offer telescopic crawlers, but on the whole their production and application has been distinctly limited.
They combine the set-up and operating speed of a telescopic mobile AT or RT crane with the pick and carry ability on unmade ground of a lattice boom crawler crane. On the other hand, they also lack both the strength of lattice crawlers and the mobility of RTs. But if the experience of one French housebuilder is anything to go by, maybe more contractors should consider adding them to their equipment armoury.
Comet (Construction et Methodes Ile de France) is a subsidiary of the Groupe Ancel and specialises in building private homes, flats and smaller office buildings in the greater Paris region, an area inhabited by 15m people, or 20% of the whole French population.
While France is a country that has long appreciated the merits of tower cranes, Comet managing director Patrick Sparfel reckons they are too static, too difficult to move around, and are not the right instrument for lifting building materials around his sites. He prefers crawler cranes and until late 1998 used lattice boom models. Now, though, he runs a fleet of six 613R Sennebogen telescopic boom crawlers: one older 12t model and five newer 16t capacity machines.
“These cranes are very handsome and sensitive to operate, they are fast and we like the fact that they can travel with loads of several tonnes”, says Sparfel.
The old cranes did not meet European regulations so they had to go, he says. “We chose Sennebogen because it is a European engineered and manufactured product which gives good value for money. And we couldn’t find any comparable machine on the market.” Comet’s cranes are mainly lifting 800kg pallets with bricks and other building materials at radii of 12m or more. A small wheeled loader assists every crane, carrying the brick pallets over longer distances from the trucks parked off-site.
At 9m high, the cranes are small enough to move between sites on a low-loader. “One big advantage is the fact that the telescoping cranes are ready for work when they arrive,” says Victor Pereira, head of Comet’s technical department.
Sennebogen says that the 613R can be used as a crane or, by adding one of a range of attachments, as a forklift or an aerial work platform. The undercarriage can be widened hydraulically from 2.3m to 3.3m for extra stability.
The cranes are equipped with an 18.8m three-section boom which is fully hydraulically retractable. Heart of the drivetrain is an 88kW Deutz turbo- charged, water-cooled engine. The basic version of the 613R features a crane winch with 40kN line pull and hoist speed ranging from 0 to 93m/min. Comet ordered the Krüger load limiter which states load, angle of boom and other features on a digital display. Additional floodlights, interval horn and an electrical diesel pump are also on the option list together with a protection trellis for the upper cab window.
