Conveying the Latest Technology
August 1, 2007
Conveying the Latest Technology
By Sam Gazdziak, senior editor
Suppliers of conveyors, belts and peripheral equipment keep developing products focus on food safety.
Meat and poultry processors are continually under fire to produce the safest possible product. Between government regulations and the negative publicity that comes from product recalls, every aspect of the process has to be considered with food safety in mind. The conveyors that transport the meat from one part of the plant to the next cannot just be looked at as a manner of conveyance. Potentially, they can be one more preventive measure in the battle against contaminants and bacteria getting into the food chain.
Design of conveyors has changed after processors requested systems that helped reduce sanitation time, says Marsha Spakowicz, executive sales and marketing administrator for Arrowhead Systems Inc.
“To achieve this we have a very special frame design, one that is ‘open frame’ for high visibility, eliminating the need for tools to disassemble. With our latest design we have eliminated all hollow tubes from the construction to prevent a potential contamination growth zone,” she says. Additionally, Spakowicz adds that belting has seen a “tremendous effort from the manufacturers to provide belts that are highly washable and also easy to remove.”
Belt Technologies Inc. manufactures conveyors and belts out of stainless steel.“Steel belts can be cleaned with steam, ozone and chemicals. Stainless-steel belts do not have interstices that can trap bacteria, which means they can be cleaned in place,” says Patrick Harper, sales and marketing manager. The stainless-steel belts also have the advantage of going into applications where fabric, plastic and fiberglass products cannot.
Modular plastic belting has seen considerable changes in recent years. “Intralox invented modular plastic belt technology on the premise that plastic was easier to clean. That was 37 years ago, and since then we’ve continuously brought to the market innovative products to meet our customers’ requirements,” says Manoj Thomas, business development analyst, meat, poultry and seafood division for Intralox.
Thomas says that Intralox has hundreds of different modular plastic belt combinations designed for specific industries or applications.
“There are new materials for X-ray and metal detection, and new designs developed for specific applications, such as those found in tough microwave environments. Some of our recent technologies go beyond just conveying, affecting the product itself,” he says, adding that belts, sprockets and other conveyor components have been designed to improve cleaning efficiency.
Along with keeping the food safe, the conveyors and belting have to keep the food intact. Allison Cox, marketing specialist for Habasit Belting LLC, points out recent developments have improved product handling. “Smaller pitch belts allow for tighter transfers of smaller products, reducing product damage and improving product orientation,” she says. “Belts assembled with rollers for sortation and accumulation reduce line back pressure, reducing product damage and allowing longer conveyor lengths with fewer drives.”
The use of the right belt in the right location can do more than improve food quality. Kerry Smith, marketing manager for Ashworth Bros. Inc., says that its Advantage hybrid spiral/turn-curve belts can improve the efficiency of a processor’s spiral freezers. Because its belts are designed with stainless-steel cross rods, its plastic modules can be thinner.
“A thinner module allows a greater open area, resulting in more airflow through the belt and less pressure drop throughout the freezer,” he explains. “The pressure drop across an Advantage belt is tremendously reduced, allowing the use of smaller evaporator fan motors, which is the largest contributing factor in a freezer’s refrigeration load.”
Developed as an alternative to existing belting types, several companies have touted the benefits of homogeneous, sprocket-driven belts made from extruded thermoplastic.
“With the implementation of stricter hygiene requirements, plants are looking to eliminate or reduce the possibility of having and bacteria. [A thermoplastic belt] works and functions like a modular belt, only it is totally hygienic and very easy to clean, thus reducing and type of bacteria buildup,” says Denise Buongiorno, vice president sales-Americas, for Volta Belting. “[Processors] can clean in place without having to remove the belting, which is typical for a modular-style belt.”
Barry Whitman, vice president of market development for Mol Industries, says that the homogeneous positive-drive-style belting positively affects four main areas in a plant.
“Food safety, sanitation, processing and maintenance, it’s a net positive for all departments,” he notes. “What you have is a positively driven belt that runs on absolutely no tension whatsoever, yet has no hinges or pins to harbor any bacteria.”
Another benefit to modern types of belting is that, unlike the flat belts that ran around pulleys, they don’t run on tension.
“If you put any type of conveyor belting under any type of pre-tension, you start creating other issues,” Whitman explains. “You start creating tracking problems and stress problems within the belt. Pre-tension in a belt is the enemy of the belt.”
Mol’s ThermoDrive belting, being sprocket-driven like modular belting, requires no pre-tension. Changes are taking place in more areas than conveyors and belting. Motors are also continuing to become more innovative. Mark Robertson, sales and marketing for Van der Graaf, notes some new developments in drum motor technology.
“Typical systems have motor and gearbox externally mounted on the conveyor,” he says. “Modern systems utilize drum motor technology.” Drum motors, he says, eliminate external components and improve operator safety and space savings. They are also completely sealed from the environment, and some models can withstand a washdown as tough as 2,000 pounds per square inch (PSI).
“Drum motors eliminate the need of periodic maintenance like greasing pillow block bearings, replacing chains and belts, and alignment issues,” he adds.
Each meat-processing facility is going to have a specific schedule for cleaning the conveyor systems, depending on the type of products produced. “Chemical selection can be tailored to the specific proteins and fats for each product, increasing the effectiveness of the sanitation process,” says Cox. “Clean-in-place systems like the Habasit Modulclean allow for the applications of cleaning and sanitizing to be applied at points that are most critical.”
Whitman says that while some belts have to be removed from the conveyor system and be soaked for several hours to clean, the extruded thermoplastic belts don’t have to be removed in order to be cleaned. “The scheduled cleanup is basically whatever time it takes to clean the conveyor running the belt and the machinery around it.”
Thomas notes that validated cleaning procedures, use of the right cleaning agents, and design of conveyors for cleanability are a prerequisite for good cleaning results. “Intralox belts designed for food applications do not need to be removed from the conveyor to be cleaned.”
Conveyor belts can be made from a variety of materials, and the proper material needs to be matched up with the proper application in order to get the best results. For example, Whitman notes that for an application such as breading, where a processor would want to recapture loose materials, wire belting would be appropriate because of the gaps in the belts.
Smith notes that stainless-steel belts are often used for cooking, cooling and freezing processes. “Stainless-steel belts are compatible with oven temperatures up to 2,000 F. Low temperatures are typically not a concern for steel belts, as they do not become as brittle as many plastics can,” he says.
The choice of conveyor belt also depends on the temperature of the specific application. “Plastic modular belts are made from a variety of materials to meet all application requirements regarding temperature, chemicals and abrasion,” Cox explains. Polypropylene has a continuous temperature range of 40 to 220 F, while nylon’s is 0 to 300 F.
The latest on the market
Companies involved in the conveyors industry are continuing to produce new items to help processors further improve product and processes. Harper says that Belt Technologies has a new line of conveyors that is true stainless conveyors.
“The conveyor and belt will be stainless steel. The conveyors will have smaller pulley diameters than typical steel belt conveyors, allowing the belts and conveyors to be used in transferring product as well as cooking, freezing, baking and packaging,” he says.
Habasit’s newest product is a M2510 Flat Top, an easy-to-clean one-inch-pitch plastic modular belt for medium-duty applications where ease of sanitation is a concern. The scalloped hinge design creates a substantial gap through which debris can be removed easily as the belt moves around the conveyor’s sprockets.
Intralox recently introduced two-inch and one-inch-pitch SeamFree belts, consisting of the Series 850 Minimum Hinge SeamFree Belt, the Series 800 Open Hinge SeamFree Belt, and the Series 1650 Minimum Hinge SeamFree Belt. Along with having no seams and a reduced number of hinges, these belts have a flume design that channels debris from the belt edge for easier cleaning. They can be used with the company’s EZ Clean In Place system and Angled EZ Clean Sprocket for extra savings in time and water usage. The patented Angled EZ Clean Sprockets provide cleaning access to 100 percent of the belt’s underside. As the belt rotates, the sprocket engages different portions of its underside, exposing each section of the belt for most efficient cleaning.
Mol Industries has several new products for its ThermoDrive line. “We’ve developed a belt that goes over much smaller sprockets for tighter transfers. We’ve got a new belt that’s perforated for drainage. We’ve got a new cleat design to carry product up an incline,” he says.
Spakowicz says that Arrowhead Systems’ NeXtgen Ultra conveyor system features open-frame construction, tool-free sanitation prep and a “minimal wear parts” philosophy. “Our system will reduce the sanitation labor, decrease the maintenance cost and reduce hot water and chemical usage,” she says.
Ashworth’s Advantage 120/200 Series belts are the only spiral/turn-curve conveyor belts both tested and certified by NSF and USDA for use in meat and poultry-processing plants. The 200 is tested for 100,000 cycles at 300 pounds maximum allowable tension in a curve/spiral application, making it the highest strength belt in its class.