Conveyors spiraling upward
Sept. 1, 2012
by Charlotte Atchley
Spiral conveyors help a bakery’s production line go a long way in a small area. They save square footage by taking advantage of vertical space, and the continuous belt eliminates transfer points that are danger zones for misaligning or damaging products.
Spirals have become a staple that streamlines the bakery — either as a proofer, freezer or cooling system — so manufacturers of these conveyors continuously revisit the design and engineering of these towering turnpikes to streamline them even more for sanitation and improved production runs and maintenance.
Cleaning up design
As the industry looks for ways to prevent recalls and food safety issues, equipment manufacturers have chipped in by approaching spiral conveyor innovations from a sanitation standpoint. In fact, the latest technology updates to such systems make them easier to clean and harder to muck up in the first place. Manufacturers have found ways to air out the conveyor by reducing or eliminating the spiral cage that has always made cleaning a chore.
In the past year, G&F Systems, Roosevelt, NY, rolled out its Spiral Evolve system, a cage-free spiral system without the drum drive. The system is easier to access and clean without a cage surrounding it.
More open design spirals are in vogue. Other manufacturers are also finding ways to get some room inside the conveyor system. IJ White, Farmingdale, NY, focused its new technology research on making spirals easier to maintain. “All these innovations, including the elimination of sprockets and drive chains, make the system more open for easier cleaning, sanitation and maintenance,” said Peter White, the company’s president.
In pursuing these ideals, the company redesigned its spiral conveyors to eliminate the horizontal and diagonal support systems found on conventional spiral cages. Removing the braces and internal structure greatly reduces the surface area that needed to be cleaned. Without a cumbersome cage, a baker can bring a clean-in-place system into the center of the spiral for a full rinse, wash and sanitization cycle.
Tecnopool, a conveyor manufacturer based in San Giorgio in Bosco, Italy, whose equipment is distributed by ABI Ltd., Concord, ON, also pursued a more sanitation-friendly open-spiral design. Tecnopool, though, replaced the large drum drive used to turn the entire conveyor with sprockets that turn each tier. Without the need for the drum drive, the inside of the spiral remains open for cleaning, and the many smaller sprockets consume less energy to move the conveyor than a single drive.
IJ White’s Direct Main Drive System, launched about two years ago, eliminates the need for chains, sprockets and lubrication on its spirals by engaging the drum drive directly with the shaft of the spiral. According to Mr. White, choosing this direct-drive system over a chain drive will reduce maintenance costs and also improve sanitation because the design removes a chain drive’s ancillary equipment — chains and sprockets — two fewer things that need to be lubricated, cleaned and replaced.
These improvements mean not only better sanitation, but also that companies can save on energy by spending less time, energy and resources on cleaning the equipment.
“If you’re spending less time on maintenance and cleaning, you can spend more time producing,” Mr. White said. “These direct-drive systems, coupled with CIP, use less water and take less time to clean. For bakeries in today’s competitive environment, lower water usage and reduced electrical and maintenance costs are all key to lowering their operating costs.”
With more bakers asking for plastic belts, Ashworth Bros., Inc., Winchester, VA, developed its Advantage modular plastic hybrid belt to address the bakers’ need for plastic while avoiding sanitation challenges associated with plastic belts. With a fully modular plastic belt, the modules need to be denser for belt strength. At the inside edge of the belt, these modules tightly collapse in order to engage the spiral drum, and the density of the belt can trap debris that is difficult to remove and clean. Ashworth’s hybrid belt has an open-module design that prevents product debris from becoming trapped around the rod. The rod freely moves within the design, allowing for debris to fall through the belt as it exits and re-enters the spiral.
Because the belt actually touches products, its sanitation is crucial. “Bakers want conveyor belts that ultimately do not have to be cleaned, would never wear out and don’t cost anything,” Marty Tabaka, Ashworth’s sales director for the Americas, said with a laugh. While the company strives to make these dreams a reality, so far easy cleaning is as close as it gets to no cleaning at all. Continuous belting and fewer nooks and crannies around the belt simplify sanitation.
Continuous belting equates to one belt throughout the system from spiral infeed to discharge. By using the I-Drive system developed by Intralox, Harahan, LA, conveyor specialist Capway Systems USA, York, PA, achieves a truly endless path.
“There’s one belt to sanitize versus an infeed to a spiral, a discharge from a spiral and the spiral itself,” said Frank Achterberg, president, Capway Systems USA. “You get all these different conveyors that need to get cleaned up. You pretty much eliminate that by having one belt on one system.”
Ashworth addressed the need for greater sanitation by improving the weld on its Omni-Pro belt. The 360º buttonless weld is free from surface imperfections and crevices, which improves sanitation and reduces the possibility of bacteria entrapments. The hygienic design of the Omni-Pro belt has also received BISSC verification, according to the company.
“We know when you’re running production, you’re making money, and when you’re cleaning, you’re not,” said Jonathan Lasecki, Ashworth’s chief engineer. “So we can keep cleaning cycles and sanitation cycles to a minimum by making the belts easier to clean.”
Mr. Tabaka pointed out that the same belts Ashworth Bros. supplies to the baking industry are also used by meat and poultry processors, so the company designs its belts to meet sanitation requirements above and beyond what’s required for bakery applications.
Wider, longer and faster
Beyond keeping a spiral conveyor system clean, bakers want this equipment to work — and work well. Bakers need to increase output and diversity on fewer but larger lines. Many of the updates spiral manufacturers have made to the conveyors assist with sanitation yet provide production and maintenance solutions as well.
Having one continuous belt not only means cleaning is easier, but it also eliminates transfer points, which cause problems such as damaged or misaligned product that must be corrected before packaging.
Every time a product transfers between conveyors, its alignment can change, especially when conveying loaves. “If the product is starting to rotate and misalign, you need to take care of that in your packaging area, and that usually means manpower,” Mr. Achterberg said. “If you don’t disorient the product and deliver it to the slicing and bagging area, then everyone is happy.”
Transfer points where conveyor widths change can cause special problems. This typically happens between the oven and spiral cooler when a wide conveyor sends products to a narrower one. Now, however, equipment suppliers have redesigned their spiral conveyors so that the belts match in width, thus avoiding damaging transfer points.
“Bakers want wider production lines, but to do that you need wider belts,” Mr. Lasecki said. “Ashworth Bros.’ smooth weld design also happens to be a stronger weld that can handle more tension than a typical one. Ashworth designed the Omni-Pro belt to operate on wider production lines and carry heavier product loads. Specifically, Omni-Pro belts’ Zero-Tension design allows for higher load-bearing capacity.”
The open modules of Ashworth’s Advantage plastic modular belts also decreases dwell time in cooling and freezing applications because the combination of open modules and steel rods allow for better airflow around the product. A fully plastic belt without metal rods needs more plastic to ensure the belt’s strength. This leads to a denser belt with smaller openings in the modules that hinder airflow around the product.
To make wider belts possible on a spiral conveyor, IJ White developed its wide system technology to support belts up to 60 in. wide. This system keeps the belt lying flat with minimal vibrations, which reduces product movement and allows the wider belts to achieve faster production rates on high-speed production lines.
The airier cages designed by equipment manufacturers also help make cooling and freezing processes more efficient. A more open design in the center of the spiral fosters better airflow in both cooler and freezer.
Maintaining form, function
Faster and longer production runs are only possible, however, if the equipment is easy to maintain. Therefore, equipment suppliers streamlined conveyors with less moving parts, which means fewer parts to break or replace. With its patented Direct Drive System, Intralox simplifies the spiral conveyor and eliminates overdrive, belt slip and friction by engaging the belt edge directly with the drum. The system also minimizes jams, product migration and issues with belt tensioning, according to Rod Markovits, global spiral manager for Intralox.
IJ White’s Direct Main Drive System also improves maintenance as it eliminates high maintenance drive chains and sprockets. For bakeries that still want to use a chain-drive system, IJ White’s adjustable drive circle allows the spiral cage to expand and make adjustments for chain stretch and wear expansion.
Tecnopool uses sprockets to power its spiral conveyors, but the company opted for easy maintenance. Nicola Scudella, North American sales manager, acknowledged that customers don’t like to wait for technical service from an overseas vendor. “All the sprockets are very easy to maintain. It takes 1 minute and 30 seconds to replace a sprocket without taking out the main shaft,” he said.
G&F Systems’ Spiral Evolve system has a positive drive belt that eliminates the need for overdrive that exist in conventional low-tension spiral systems, so the spiral conveyor avoids overdrive maintenance issues that can plague a bakery. The positive drive also extends belt life because the belt no longer wears against a vertical drive bar for rotational movement.
When Ashworth designed its Omni-Pro belt for heavier loads and better sanitation, it also took belt life and maintenance into consideration. The company’s patented coining process prevents break-in wear, reduces belt elongation and increases belt life. The Omni-Pro link design also incorporates a patented Protrusion Leg that prevents welds from contacting spiral cage bars and enables the belt to run smoother with less system wear.
Already important to the bakery production line, spiral conveyors continue to improve the bakery process in terms of sanitation and maintenance. Today’s spirals allow bakers to meet their goals with wider, longer and faster production runs.