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 Fred Tangelder, automotive field representative for US lifting specialists Gorbel, has 20 years of experience in the sector. “The loads that are lifted in automotive construction are not huge,” he says. “I have seen loads of as little as 30lb (13kg) that need lifting equipment installed to handle them. At the other end of the spectrum might be 1,500 or 2,000lb (700– 900kg) loads; but more typical is probably in the 100–1,000lb (45–450kg) range. That will cover almost everything from a flywheel on an engine to a pressed bodyshell that is being moved to its chassis.”

Columbus McKinnon covers a similar load range for automotive industry applications. “We provide a full range of components, such as body-decking hoists used to pick up vehicle components along the assembly line, wire rope hoists, variable frequency controls and so on. They are used on cranes ranging from 1/8t to 2t small jib cranes and workstation cranes in individual work cells, all the way up to 30t and 40t overhead cranes in the stamping plants,” says Ed Butte, director of global strategy and product development.

“What is key in the automotive industry, though, is quantity and frequency,” says Gorbel’s Tangelder. “The plant may be producing 800 units on each shift. That can translate to a repeated movement every 30 seconds; and for a human operator to perform that number of repeated movements, at that frequency, for that length of time is fatiguing. So they will want assistance machinery to help with the lifting and positioning; and the technology for that becomes interesting.

“Some options are electric chain hoists, air balancers, or cylinder-driven lifting machines. The application, and that allimportant frequency rate of repetitions, might not absolutely determine the technology but it may often restrict the choice of technology that is used. For example, if an electric hoist is required to perform 800 lifts and deposits a shift, an electric chain hoist might not be the best option for that because it is slower, and the relay control will be subject to considerable wear and tear. A better choice might be an air balancer, or an H5-rated servo-driven lift.” (The H5 classification is for duty cycles approaching continuous operation with up to 600 starts per hour.)

“Higher loads, for example 200lb or 300lb (90–140kg) lifts, such as of a fullydressed engine or a transmission, will still be doing 800 cycles a shift because every sub-unit on the line must keep up with the rate of car production. Electric chain hoists are possible for that application; but to lift the larger loads you might have a large air balancer, or two units, dual air balancers, a left-side and a right-side, working in unison to pick up that weight.

“The choices come down to considerations like that, taking into account what gives the best fit to the application.

“How the lifting method is chosen in each application will also depend on what each company and its engineers want. They may have personal preferences; they may have favourite vendors and favourite brands, depending on how well products have performed in the past. Mostly it comes down to the individual engineer and his outlook, and how the sales person presents the products. “So you could have a plant that is deciding to harmonise on one technology, for example electric chain hoists, or air hoists, from a preferred vendor; its machinery and its choices will evolve over time in the light of experience.

“The other big thing in the automotive industry is down time. Even 60 seconds can matter. If a hoist or crane continually breaks down, or if it is very hard to repair when it does fail because it is complex or there are no parts quickly available to fix it, the company will try to stay away from it in future.

“So makers gravitate to the technology and products that have been up and running for longest. That truly is a huge driver in the automotive industry.

“Those considerations apply to OEMs, the big people like Honda and Toyota. They apply just as much to Tier 1 suppliers, that is, makers further down the line who supply at least one component for each car, say makers of steering modules or gas tanks. They too have to keep up that same hefty production rate, to keep up with the vehicle production rate. So if you are making a complicated component such as an engine, your cycle time is pretty close to the vehicle maker’s.”

Hands-on approach

Perhaps unexpected is that, in the US at least and to an extent in Europe as well, complete digital control is not at the forefront in automotive construction. “Digital sophistication, perhaps surprisingly, I have not seen a lot of at all,” says Tangelder. Two factors may contribute to this: “Automotive has traditionally been a labour-intensive industry, and people tend to stick with what has worked well in the past.

“And many applications dictate a handson operation at the point of delivery. Taking components out of dunnage is an example. When you are unloading parts they will be densely packed together so that they are optimised for the number of parts on a pallet. That means they may be too closely packed for the gripper mechanism of a hoist easily to take hold of them. That presents a problem for automation; but it is no problem for a human operator who has an assisting technology on his lifting machine.

“Similarly, when bringing a component onto the assembly line it may have to be deposited in exactly the right orientation onto the component that is already on the line. Boltholes must exactly align, locating pins must engage, and so on. Several surfaces must line up exactly and simultaneously. The human eye and hand may still be the most cost-effective solution to that, as long as help is given to the human muscles involved. So such lifting and positioning applications tend to be as automated as possible, but with the operator still driving it by hand.

“And he or she is still doing 800 handson operations per shift; which means that ergonomics is therefore a big player in design of your lifting apparatus. For maximum productivity you try to filter out as much human error as possible, so lines and machines are very highly engineered to reduce or eliminate those human errors that could be introduced. That is the goal of any company making the tools for automotive production.

“Such toolmakers would like to go to total automation, but it is cost-prohibitive. The density of parts, as we have seen, is one factor. The density of operators is another. Substitute a robot arm for a production-line operator and that robot has to be fenced in, for safety; and that takes up space along the line. Indeed it can easily multiply the length it needs on the line three-fold, or even by a factor of five. A line five times longer than it needs to be is not cost-efficient. So manufacturers still use human operators, because it is sensible for them to do so.

Safety features include configurable restricted areas or ‘no-fly zones’, where normal operation is either not allowed or limited. “We provide systems that can designate areas where cranes are programmed to stop or slow down. There are remote control bellybox transmitters for ‘go/no-go” situations.’ Another unique system, ideal for the automotive industry adds Butte, is the Pro-Path Automated Workstation Crane. It is available in semi and fully automated configurations depending on application needs.

Julian Champkin looks at lifting requirements in the automotive industry