If speed alone drove the value of conveyors and sortation systems in high-throughput facilities, equipment manufacturers would have it easy. Systems would be designed to whiz cartons around with a whir and a clickety-clack. Records for speed sorting would be broken and products hurtled out the door.
But, in the sober reality of today’s material handling universe, faster—while still vital—does not necessarily equate to better. Though manufacturers may tout a conveyor’s blazing speed, real-world conveyors require more than just feet per minute. When product is snaking through a facility’s central artery, efficiency and safety are just as vital.
With automation playing an ever-greater role in product manufacturing and distribution, the importance of smart conveyors and sortation systems has increased exponentially.
“If you look at the justification for automation, it’s more than just the moving of goods,” says Gregg Vandenbosch, product manager for sorting and conveying at Dematic in Grand Rapids, Mich. “It’s become the intelligent routing of those goods.”
For equipment so central to the operation of industry, conveyors have evolved only modestly in recent decades. According to Bob Reinhartson, senior account executive for Carlstadt, N.J.-based W&H Systems Inc., the most significant advances come from attempts to make systems both faster and quieter.
“Basically, you have three key issues,” says Tina Hogel, account manager for Caljan Rite-Hite Inc. in Denver. “All three are equal. We’re trying to design these to run as fast, safe and accurately as possible.”
Conveyor and sortation manufacturers have focused on simplifying installation and maintenance, making the systems more reliable and designing them with greater flexibility for future needs.
Tackling the Transition
One of the most daunting challenges with any new conveyor system is the sheer task of implementation. Rarely are these systems built in a new facility. More often, they are constructed in phases, requiring meticulous planning so as not to disrupt processes.
That task has only grown more challenging as conveyors, and the respective operations they help run, continue to evolve into more complex systems, according to W&H’s Reinhartson. “The processes have become more involved. There are value-added services—and that’s made them more difficult,” he says.
In addition, demand is increasingly shifting to 24-volt wiring that does not require conduit, according to Boyce Bonham, manager of quality assurance at Jonesboro, Ark.- based Hytrol Conveyor Co. Inc. “You used to have a field electrical drop to every motor,” he says. “One thing we’ve done is reduce the number of motors. We do a lot of the wiring in the factory rather than in the field. All the inputs and outputs to the PLC are plug and play. When the equipment arrives, all the cabling goes into easy input-output points. It’s all matchmarked, so you know where everything goes.”
Also helping to ease the transition is the increased sophistication of controls. “Our controls package for our sorters used to take several hours to configure,” says Bonham. “But, now, after the sorter control is plugged in, the system’s ready to operate, and it automatically calibrates the lanes and the distance. It’s all done automatically.”
Perhaps the biggest evolution in sortation systems and conveyors is the increased emphasis on flexibility—both in terms of size and scope and also the ability to process product.
Sortation systems today have the capacity to run up to a staggering 650 feet per minute. But, not every customer has a need to ship out 90,000 cartons per day. One size, clearly, doesn’t fit all.
“It’s all about modularity and flexibility—what I call scalability,” says W&H’s Reinhartson. “We always try to ask for growth projections and find out where a company expects its business to be in five years and then in 10 years. We try to design the initial system, but we’ll do it with an eye on a 10- year projection and try to scale it back for what their needs are now and for the immediate future.”
That modularity comes in the form of conveyor frames that stay in place, allowing technicians to upgrade existing components quickly and fairly inexpensively—all without having to remove and reinstall equipment.
W&H’s RSU tilt-tray sorter features a hinge door at the bottom, which opens up and releases product into chutes. According to Reinhartson, the system is generally less expensive than traditional tilt-tray sorters and provides value for a target audience. “It hits a niche that’s an important part of the market because a lot of people don’t need those superhigh- rate sorters,” he says. Though slick brochures highlight dizzying numbers for throughput capability, manufacturers are offering more products geared toward the needs of each customer.
“Throughput is trending upward, but I see a lot of tailoring of products to specific ranges of throughput,” says Dematic’s Vandenbosch. “I might have a product that’s great at providing 400-plus cartons per minute, but with that performance comes a higher cost. So now you see more time spent trying to match price to performance class. The equipment’s becoming more tailor made to specific industries and throughput requirements. I call it price point.”
After all, not everybody wants to pay for a sorter that can do 400 cartons per minute when all they need is 150.
Maximizing Existing Technologies
Changing throughput rates doesn’t necessarily mean constructing a new sortation or conveyor system. It also can come by way of changing the way the technology is used. In a struggling economy, one of the easiest ways to upgrade a system is to tweak an existing one.
“One of the things that excites me the most is getting control sophistication to the point where we automatically vary the speed of the system based on real-time demand,” says Caljan Rite-Hite’s Hogel. “That’s something that’s very well received by our customers.”
Hytrol’s Bonham has seen his company’s new Generation 3 EasyLogic control create adaptability in existing systems. “By upgrading the controls, you can actually make the equipment handle longer cartons just as efficiently, without having to replace the hardware,” he says. “We’re anticipating more of that in the months ahead.”
Another trend cited by Hogel is finding more efficient ways to maximize space. “I’m seeing more facilities trying to get rid of the air between cartons,” she says. “Years ago, you needed to have 12 inches between cartons to make the divert off the sortation system. Now, it’s down to six inches between cartons. When you do that, it’s diverting more of them out the door, and you don’t have employees trying to push cartons on roller conveyors. Conveyors feed product directly into a truck.”
Built to Last
Any system that runs 24 hours a day, seven days a week, will push the resiliency of its components. In the case of conveyors and sortation systems, motors and various moving parts undergo considerable stress.
| Speed, safety and accuracy are equally important features of conveyors. |
To combat this, manufacturers have devised several innovations. Hytrol, for instance, is trumpeting its 24-volt DC roller conveyor for its durability. “You’re seeing it more and more: The industry is moving toward 24-volt,” says Bonham.
Motorized rollers, until recently, hadn’t been particularly durable. Traditional, 24-volt conveyors had DC motors and a set of gearing built inside the roller. Hytrol’s innovation with the E24 system is to take the 24-volt motor out of the roller and place it on the side frame of the conveyor, according to Bonham, thereby extending the life of the motor.
Additionally, more motors are being equipped for variable frequency drives, allowing users to run conveyors at different speeds depending on seasonal requirements.
Hogel believes one of the biggest advancements in durability is the transition to fewer moving parts. Caljan Rite- Hite now uses photoelectric accumulation technology on its conveyor, which allows for equal spacing between cases to eliminate product damage and jams. The technology replaces high-maintenance air actuators.
| Sequencing has forced wholesale changes in how product is sorted. |
“I would say there’s about 25% to 50% fewer mechanical parts in a lot of systems,” says Hytrol’s Bonham.
Just as important, says W&H’s Reinhartson, is the increased quality of those parts. “What’s really helped reliability and durability is that there are more precision components,” says Reinhartson. “Taking the pneumatics out of the switching devices has reduced the components and made them more reliable.”
The Next Frontier
It seems like another age—and perhaps it was. Three decades ago, before automation was the standard for distribution and manufacturing facilities, the movement of goods was largely focused at the pallet level. The challenge back then was getting the right pallet in the right truck.
That system has given way to a far more retail-friendly system. An increasing number of retail stores don’t want entire pallets. Rather, they want several cases of one product and perhaps one case of another.
We are now entering a tailor-specific age of pallets—and conveyors and sortation systems are gearing up to meet that challenge. “That trend starts to go down in finer and finer granularity of product movement,” says Dematic’s Vandenbosch. “The sequencing issue is a big opportunity. It takes a lot of labor to identify and stake out a trailer’s worth of product into the right sequence. That, to me, is one of the biggest trends I’ve seen in the last year and a half.”
Sequencing has forced wholesale changes in how product is run through sorters, fine tuned through additional sorts, then manually placed on pallets. Years ago, Dematic’s Mini-Shuttle and lifting beam lent itself to specific sequencing. However, its throughput was better matched in Europe than in the U.S.
Vandenbosch sees that technology taking another step. “What we’re seeing today is a three-dimensional sorter that has mini-load storage retrieval capability and also an output side that can be sequenced in whatever order you like,” he says. “It provides a through-put of four to five times that of a traditional load-handling device. And, it ends up being a combination in which traditional sorting and conveying products work with new products to deliver case-level goods in a desired sequence.”
Stealth Yet Sophisticated
For example, Interroll’s 24-volt DC RollerDrive was installed for Material Handling Technologies (MHT), a Morrisville, N.C.-based company specializing in the design and implementation of material handling systems.
MHT wanted a sophisticated roller drive for its new conveyor system. The roller drive had to be cost effective as well as intelligent. MHT partnered with Interroll to develop a new 24-volt DC conveyor system called StealthZone. The StealthZone uses Interroll’s EC100 RollerDrive and HC-EC100 DriveControl card.
In consecutive single-zone accumulation applications, the EC100 RollerDrive and HC-EC100 DriveControl card work together to allow the StealthZone to provide non-contact, zero-pressure accumulation logic control. The system activates conveyor zones individually or together, an ability that allows it to handle varying throughput rates, unit sizes and traffic patterns. Specific conveyor zones operate only when required, thereby saving energy costs.
Smart Yet Simple
St. Louis-based FKI Logistex claims to have found a balance between the two with its onconveyor Logistex ZC200 Zone Control logic control system. The ZC200 features smart functionality, such as the ability to interact with cranes and robots and implement stop or work zones. The ZC200 is preprogrammed with logic options that can be changed with the flip of a DIP switch.
“The choice to go with a DIP switch was two fold,” says Jerry Koch, product director, software and controls. “One, to ensure that FKI Logistex can train staff to change programs easily, and two, to decrease maintenance and spare parts needs without sacrificing flexibility.”