HEAVY LIFTING Ӏ SECTOR REPORT
length and weighing between 450 and 630 tonnes. For each stage the JS-250 raised the bridge deck three metres clear of the bridge abutments. Two pontoons were positioned underneath, and the bridge deck lowered onto steel frames resting on support structures. The bridge was then floated to the side and lowered on to SPMTs for transportation by road to a nearby site for dismantling. The task was competed over a two-week period. The close proximity of a busy
highway meant that precise operation of the JS-250 was critical. As standard the JS-250 features an adjustable top barrel, including a double-acting lock nut cylinder with swivel saddle, for each of the four lifting towers. The cylinders can be extended, allowing precise adjustment of the starting height of each leg, ensuring safe and stable lifting. “Space restrictions at the site made this a very challenging project,” said Max Boere, team leader SPMT at Autokrane Schares. “The compactness and ease of set-up, together with accurate synchronised lifting, made
Engineered Rigging’s Enerpac SBL500 hydraulic gantry
the Enerpac JS-250 a perfect fit for this project.” Engineered Rigging is another company that has added to its Enerpac fleet. In its case the addition was an additional Enerpac SBL500 Hydraulic Gantry. The gantry has a lifting capacity of 500 tonnes and is designed for infrastructure projects at ports, railways, power and industrial plants – basically any civil or commercial construction application where traditional cranes will not fit and overhead cranes are not an option. Each of the gantry’s four legs has internal three-stage double- acting hydraulic cylinders and self- propelled steel wheels for travel on skid tracks. Each lifting tower has a counter-balance valve, stroke sensor and pressure transducers. Technicians can remotely operate the lifting towers either independently or as a group of two, three or four towers – wirelessly with the Intelli-Lift control system or, if site conditions dictate, via a control cable. Additional features of Intelli-Lift include load and height readings for each tower, and synchronised lifting and travel.
As Sel says, even heavier loads
may be lifted in the future. There is, though, another possible limit that we may now be reaching: that of size. Large but not necessarily hugely heavy loads are transported; they are moved on skids, or on SPMTs, and sometimes over many kilometres. The physical access required to transport such things – removing street furniture, negotiating low-headroom bridges, raising power cables and the like – must surely impose some kind of limit to what can sensibly be moved? Is this a challenge? What does he think will happen her over the next five to ten years? “Size and volume are indeed
approaching logistical limits,” he says, “posing significant challenges. Transporting large components often requires extensive planning and infrastructure adjustments. Over the next five to ten years, we expect advances in modular construction techniques, improvements in transportation infrastructure, and the development of more sophisticated logistics planning tools to help address challenges that may arise.” Transport infrastructure may
deliver better roads able to bear higher axle loads, but presumably will deliver with it more in the way of overpasses, overhead traffic gantries, foot- and cycle-path bridges and so on. There will be more obstacles to negotiate rather than fewer. “We also anticipate an increase in on-site assembly to reduce the need for transporting oversized loads,” says Sel, addressing that problem. The cranes themselves are ahead of the game here: “Most of our heavy lifting machines are containerisable, which is a very good answer to the logistics challenges of moving around such giant cranes.” So, giants will still rule the
earth… but they may be giants that can be split into smaller parts.
42 CRANES TODAY
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53
