June 13, 2011
material handling update | Conveyors

Does your conveyor need a tune-up?

Does your conveyor need a tune-up?

If output has slipped or your system is jamming, it may be time for a professional audit.

By Peter Bradley

Maybe output has slipped a bit. Or the conveyor system has started to jam once in awhile. Or productivity isn't quite what you believe it could be. Count those among the signs that it's time to conduct a professional audit of your conveyor system.

A conveyor audit is not an especially intimidating task. It just means taking a careful look at all the pieces—mechanical, electrical, software, etc.—and making sure they're running the way they should both as components and as parts of a system.

Conveyor makers categorize audits into essentially two types: maintenance audits and wider-ranging operational audits. Performance issues—like problems with jamming—suggest that a maintenance audit may be in order. An operational audit might be indicated if the user is looking to boost throughput or wants to make sure the system is still meeting its needs, particularly if the business has undergone substantial changes since the conveyor's installation.

Boyce Bonham, director of the integrator services operation for Hytrol Conveyor Co., says customers seek audits for a variety of reasons. "Some people want one once a year no matter what," he says. "Other customers want us to do it when something triggers it—maybe an increase in downtime due to mechanical or electrical issues or a drop in performance."

"Audits are done for a lot of reasons," concurs Kevin Klueber, product manager for Intelligrated, a manufacturer of automated material handling systems. "Maybe there have been changes in equipment or in the operational environment or in throughput requirements."

Different audits for different needs
As noted, maintenance audits aim to resolve specific problems. "A maintenance audit would typically be triggered by too much variability in the performance of the system," says Ken Ruehrdanz, market manager, distribution and warehouse systems for Dematic, a material handling and logistics automation company. "Typical issues that signal the need for a maintenance audit include downtime, a frequent need for emergency repairs, possible equipment safety violations, increasing power consumption, increasing spare parts usage, and decreasing overall system performance. Maybe there are issues with accuracy or too much recirculation."

Klueber warns that problems with the conveyor can lead to other problems. "Carton handling can be affected as equipment wears. You can get more and more jams, and that relates to product damage."

Operational audits, by contrast, focus more on the overall performance of a system. Indicators that an operation might benefit from this type of audit tend to be more subtle than the problems that typically prompt a maintenance audit.

"The DC or warehouse could be performing without any problems, but you still may not be getting the performance you want," says Ruehrdanz. "The trigger may be that you are just not getting the packages out the door. You are humming along, but you're not meeting the desired rates. Or at the end of the shift, you still have work and you have too much overtime. Or maybe you start seeing some ergonomic issues or you are not getting the order accuracy you used to. If any of your key metrics are going in the wrong direction, that's a reason for an operational audit.

"An operational audit is all about evaluating the effectiveness of the process," he adds. "Areas of particular focus include labor utilization, ergonomics, space utilization, processing time, inventory accuracy, order accuracy, and performance during peak time periods."

An operational audit might reveal opportunities for technology upgrades—even in relatively new systems, says Klueber. For example, auditors might suggest modifications that can enhance throughput or energy efficiency.

Watch and learn
The key element of either type of audit is having an engineer observe the system in operation. While an in-house maintenance staff may be able to get at some underlying issues, this is a job for an outside specialist, the experts agree. Ruehrdanz says the explanation lies in the reliability of today's systems. Because these units are so trouble-free, he says, even DC maintenance professionals may find their knowledge gets rusty because they deal with problems so infrequently. For that reason, he and other conveyor professionals we spoke with encourage bringing in engineers who work with automated systems every day.

"It's like calling in the doctor, if you will," Ruehrdanz says, "someone who can walk through and check core indicators. Let's say you have a sliding shoe sorter. If you bring in a technology expert who lives and breathes sliding shoe sorters, who knows the mechanical and electrical controls and the software, he will be able to make a diagnosis faster than a maintenance staff. Your maintenance staff may be darn good, but there may be things they are not aware of."

As for what an audit entails, Bonham offers this description of his own company's procedure. "Even before going out, we review the system," he says. "Then we go to the site and basically walk through the system while it's operating. We talk to the operators, we talk to the mechanics. We get feedback on what they are experiencing with the system. Sometimes, the solution is as simple as fixing a guide rail. Or it may be bearings—we do spot checks on things like bearings and drive components. Then we usually go back when the system is down and take a closer look at things. Afterward, we compile a report on what things need repairs and what areas need additional regular maintenance."

The good news for DC managers is that neither type of audit need disrupt their operations. In fact, doing the audit requires the on-site analyst to watch the system in action. And fixes, too, often can be completed with little or no interruption of operations. "Sometimes it is just a little adjustment," says Ruehrdanz. "Sometimes we can make tweaks right there."

Either type of audit can take place relatively quickly. For example, Klueber says Intelligrated's specialist in operational audits will spend one to three days in an operation. "He'll just walk around and watch the systems run, watch people working in the pick modules or loading and unloading trucks. He'll make some notes and run calculations and make recommendations on modifying the work flow."

Within days of the visit, the auditor should provide a written report detailing observations and recommendations. "If there is really something glaring, that would be called out and highlighted," says Ruehrdanz.

The resulting reports will likely provide managers with recommendations ranging from simple repairs to software adjustments to process changes to suggestions for systems upgrades. More often than not, Bonham says, the customer's in-house maintenance staff can implement the recommendations.

Klueber adds that these days, the recommendations often have to do with energy efficiency. "A lot of things can be done there," he says. "For instance, we can install software packages so that if a system is not carrying product for a certain amount of time, it shuts down.

More calls for audits
Bonham reports that companies are seeking audits more frequently than in the past. "They are becoming more popular," he says. "Maybe customers do not have the maintenance staff they once had. Or because equipment is more technical, they want technical expertise. Or rather than invest in a new system, they want to make the existing system last longer."

The best reason may be that an audit can be cheap, disruptions expensive. As Bonham says, "The cost of downtime is going up."

About the Author

Peter Bradley
Editor Emeritus
Peter Bradley is an award-winning career journalist with more than three decades of experience in both newspapers and national business magazines. His credentials include seven years as the transportation and supply chain editor at Purchasing Magazine and six years as the chief editor of Logistics Management.

More articles by Peter Bradley

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