TECHNOLOGY REPORT | PORTABLE CRANES
is rapid. It involves not much more than unfolding the legs and securing them in place by ball pins, and then adjusting the height of the beam to whatever you require. A hand-powered winch fixes to one of the A-frame assemblies, and a fall arrestor to the other; the rope goes between them via the moveable trolley on the beam. Unpacking and assembling can be done
by one person in a couple of minutes. After use it can be packed away and stored or taken to the next job-site in the back of a pick-up truck. It comes in three versions (standard, medium and tall), with heights adjustable up to 2.9m and beam lengths up to 4m, and can support loads of up to 1,000kg as well as people – for example, lowering an
R Caldwell’s Krane King gantry, here in the 2.0-ton version
Q Reid’s Porta
Gantry comes in different sizes…
operative safely down a manhole (and, of course, safely recovering him afterwards.) Its load limit is 500kg for people, making it suitable for up to three persons for fall protection applications. The standard Porta Gantry – the non-
Rapide version – can also be manually assembled, using just four bolts, though the components have to be fitted together rather than just unfolded. The pay-off, though, is its much greater capacity: it is for heavy lifting, of materials up to 5t. One suggested use for the Porta Gantry
Rapide is for scenarios involving confined spaces – accessing below-ground water treatment facilities, to raise a submerged pump for servicing, for lifting and lowering equipment, or for working down manholes. That is clearly one reason that man-lifting is stressed among its abilities. An alternative to portable gantries
for such uses is the portable tripod. The Tractel Tripode, for example, is just such a temporary anchor designed to be set up over manholes and the like. It can carry the weight of two workers (weighing up to 150kg each) plus their equipment and tools and has been tested to stop their fall. It can also be used as an anchor point for lifting, with the capability to raise a maximum load of 500kg. It is foldable. Made of aluminium, it
weighs only 23.3kg without accessories and is small enough to be transported in light site vehicles. The maximum height below the head is adjustable from 1.78-2.73m and, dependent on height, the distance between the legs can be from 1.03-1.58m.
f Q …and is a work of art
www.hoistmagazine.com | December 2022 | 31
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