Every member of the STG Team has a working knowledge of cranes – recognising that, as the weight and working radius increases, this can have a significant effect on the size of crane needed.
At the lower end, there are truck mounted cranes, generically known as HIAB. Over the years, these have increased in capacity and sophistication. When these ‘run out of steam’ , mobile cranes take over – when discharging from vessels, 1.000ton capacity is not uncommon – comprising not only the multi-axle base unit, but also as many as 15 support trailers, with counterweights, extra jib sections etc – the crane taking several days to erect.
Some of the larger ports offer high capacity, shore cranes – some are also able to provide floating, barge-mounted cranes.
If space is limited, hydraulic gantry systems may provide the solution. Essentially hydraulic towers, with cross beams, running on rails. These are best suited to assembling production lines – press lines for the newsprint industry, car manufacturer etc.
Two external factors always need to be taken into account – wind speeds and ground conditions. With one project, once test borings had taken place, it soon became apparent that ground conditions were ‘far too soft’. Having explored every option, the only economic solution was to sub-divide the main piece into two sections, marrying them together during the final lift process.