MONORAIL CRANES
Digital automation can be easily added to monorail systems.
Sam Upton concurs. “From my point of view, I always try to tell customers to forget about the cranes, forget about whether the load is above you or on the ground or halfway between – instead, think about the ideal flow. “Look at the movement from A to B to C to D and E via whatever workflow processes you have to do. What is the most efficient way to move that product around your factory? And then it is a case of, ‘Okay, so we know where the product has got to move to. How do we use the technology to get it there? Which bits of the journey need to be automated? Which bits are going to be better handled manually? Where do we have a crossover between the two? How do we most efficiently manage that?’,” he explains. “One element of that is precision. Where in
the process is precision most needed? Where is it less important? That again comes down to speed and to the actual process in the industry. If you are placing microchips onto a board it needs millimetre precision so it has to be camera controlled. Other processes don’t need to be like that. So you tailor the system to suit the stage of the process. If you automate, the precision is as good as the sensors and the software that you have. If you go manual, it is as good as the human eye and arm and hand.” For many applications, this is a complex, efficient and well-designed tool.
Sharing the load There is a parallel here with the material you use for your overhead tracks and runway. Steel has been the traditional medium. Aluminium has
36 | September 2025 |
www.hoistmagazine.com
recently gained traction for its lighter weight. “There are some interesting points here,” says Sam Upton. “In the market, aluminium is seen as modern, and there is a perception that aluminium is always lighter as a material. Yes, it certainly has lower density. A piece of steel will be heavier than a piece of aluminium of the same size. But, size-for-size, steel is stronger. You will find in a lot of instances that to get the same level of strength in aluminium you have to have a lot more of it, so the weight saving might not be significant at all. “Often you get situations, more so on when
you are dealing with loads at the upper end of the light crane spectrum, in which the moving parts of your crane, which on a bridge system will be the bridge itself, would be a similar weight in steel as aluminium.” And, of course, as far as energy consumption is concerned, it is the weight of the moving parts that matter. The weight of the static parts – the main runways – is irrelevant. “If you were pushing a bridge around with a load of 250kg on it, most of the weight you are moving is actually the bridge. Even so, if the steel bridge weighs 200kg and the aluminium one weighs 180kg, and your pushing force is 1% in both cases, the saving in pushing force is next to nothing. So above a certain capacity there is no advantage in aluminium. But at the lighter capacity end of the market, it certainly has a place when you’re moving loads up to around 250kg. “I do question, though, why anyone would
ever motorise an aluminium system, because 90% of the advantage of an aluminium system
has got to do with weight. And given the very low friction trollies that are around nowadays the capacities you would carry on it can be moved along almost with a finger. So why would you fit a motor? It is extra expense for no real reason, unless there’s an environmental reason for it – if you wanted it for, say, a clean room or an explosive atmosphere where operators should not go. If you want a motorised system, my advice would be to do it with steel and save the cost of expensive aluminium. You get exactly the same solution but much more cost effectively.” A big advantage of an overhead monorail,
he expands on the point, is that it moves with such low friction. “They have smart track profiles and wheels that that run and move very, very freely. The trolley is free to move and it is easy to move manually.” Not to mention moving things manually has other advantages. One of which is that if the operator works on the load in two different locations with two different machines – say to mill it then to drill into it – and walks between the machines pulling the load, then the load keeps pace with him exactly. “If you like, when you motorise something, you are losing the manual performance and convenience.” The alternatives, then, depend on the application. All-singing, all-dancing automation is easy and economical to install and sound modern and state-of-the-art and attractive. It is there, and available, if you want it. But human operators, with human brains, work capably and efficiently too. You can pay or save your money, the choice is yours.
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 |
Page 54 |
Page 55
