Tandem lift splits manufacturers
Straddle carrier customers usually plump for 40-ton single lift units or 50-ton twin lift, but today there is an increasing market demand for 60-ton expanding twin lift capability, allowing it to match the capacity on ship-to-shore cranes.
Technically, he sees few problems in adapting the classic straddle carrier or aspects of the RTG design to carry two laden containers side-by-side.
Jost Dämmgen, Konecranes sale manager for port cranes, however, is yet to be convinced by such a concept.
“Such units would have to be double the width of existing designs with a concomitant reduction in speed, meaning there would only be a very small niche market for them,” he says.
Furthermore, operators would need to seriously consider changing their entire fleet of straddle carriers, because double width units would not run comfortably alongside conventional straddle carriers, because of the need to totally rearrange the stacking yard.
“I would also be worried about the stability of such a unit,” he says.
Instead, he believes the future of this market revolves around six-wheel units operating at speeds of 40-50km/h in twin pick, two-high mode.
