Weighing the Possibilities
October 1, 2007
Weighing the Possibilities
By Sam Gazdziak, Senior Editor
New technology adds more accuracy and efficiency to weighing systems.
Considerable importance has been placed on the most up-to-date, high-tech processing equipment, but the benefits that technology brings don’t stop there. A proper weighing system helps reduce giveaway, raise profits and helps ensure that products are moved through the facility quickly and effectively.
Suppliers to the meat and poultry processing industries have worked to improving weighing systems to meet the needs of their customers. “Developments in weighing systems have been focused on increased speed, improved product handling, flexibility and the creation of more user-friendly, networkable solutions,” says Brian Barr, sales manager for Heat and Control Inc. Providing a machine that meets the customers’ needs of accuracy, efficiency and reliability and more. “The Ishida solution is focused at providing all of these within a user-friendly system that also meets today’s stringent sanitation requirements.”
Chuck Saje, special projects manager for Bizerba Inc., says that weighing systems need to provide flexibility, durability, serviceability and be operator friendly. Furthermore, marketing demands constantly change the packaging requirements, not to mention government regulations and traceability requirements that bring about labeling changes. Weighing equipment needs to be able to be upgraded and adapt to handle the changing packages.
“Weigh/price labeling units are required to perform many complicated functions. The very nature of high accuracy and high speed demands sophistication.” However, he adds, “Plant conditions are harsh, and although the equipment employs sensitive and high-tech electronic systems, it has to be able to withstand a wet and cold environment.”
Weighers have had to be designed to withstand the environment found in a plant, adds Kyle Thomas, marketing manager for Mettler-Toledo Hi-Speed. “Development of a true harsh environment, high-accuracy weighing assembly such as the Mettler-Toledo IP69K electro-magnetic force restoration (EMFR) load cell enables users to significantly tighten up tolerances while surviving the normal day-to-day operations of meat and poultry customers,” he says.
The supporting equipment can also boost the abilities of a weighing machine. “In the case of dynamic weighing,” adds Ingolf Latz, director of international sales - checkweighers for OCS Checkweighers, “one could say that 90 percent of the success — avoiding under filling and reducing the giveaway factor — comes from proper product handling.” Latz says that the right weighing technology, combined with selected and well-designed components have a tremendous influence on the quality of weight reading.
Scaling up innovation
Recent developments in weighing technology have been designed to improve upon the efficiency of the equipment. Gainco Inc. has combined vision grading applications with its current line of weighing products. “The marriage of vision grading with advanced weighing system technology is ideal for processors who are producing value-added, whole-muscle further processed products, particularly portion control items such as filets, tenders, nuggets and strips,” says Russ Williams, marketing manager. That technology, he adds, “identifies quality defects and, along with precise weighing information, accurately distributes both incoming and finished products to any number of locations for either further processing or packaging.”
Accuracy is a key issue for weighers, naturally. Saje says that Bizerba has developed scales that can operate dynamically at 0.002 pounds resolution. “At first glance, two thousandths of a pound doesn’t seem very important,” he says. “However, with processing speeds reaching 120 packages per minute or more when total line production capacities are extrapolated, this difference translates to thousands of dollars by tightening controls on overweight giveaway and tare weights.”
Weighing systems have developed to the point that they can help monitor other parts of the process. Systems with tendency control are able to compute an average for a set amount of packages weighed, Saje notes. In the event of a difference between target weight and computed average weight, a control signal is sent to the connected filler, portioner or slicer. “Vision-based selection uses camera scans of the product to select or verify particular visual attributes and is refined to a point where even lean/fat ratios can be detected in meats,” he adds.
Williams says that, along with accuracy and speed, ease of operation and calibration are important attributes in weighing equipment, as well as user-friendly menu navigation for the operators. He also notes the importance of convenient data transmission, such as “reporting capabilities to a central network or database and transmission of data to peripheral devices, such as label printers, for example.”
There is more to consider than the weigher’s abilities, of course. “In addition to machinery performance characteristics, one must also look at a supplier partner’s ability to support the equipment for the life of that machinery,” Barr says. Because correct operation is so important to fully realize the benefits of a weighing system, Heat and Control stresses the importance of proper training. “We have also developed tools and training curriculums to optimize our customer’s ability to run their products day in and day out with the confidence they are getting the most of their investment,” he adds.
Developing equipment that meets the needs of a company’s staff is paramount. “To comply with the labor force available to the production plants, all Bizerba units are designed with tiered operation levels that are designed to allow protected interfacing at each level,” Saje points out. “Visual touch screens have been developed that allow multiple language and selected operation points to be displayed according to the user’s ability and assigned tasks.”
The sanitation staff should also be considered along with the operating staff. “Open frame designs, which are easy to be inspected visually and easy to be cleaned with a high-pressure steam cleaner, are in demand,” Latz says.
For the processor that is looking for a new system, Saje advises, “Use a modular design system, integrated with other equipment used on a line. Don’t skimp on label quality; on automated operations you will waste more than you saved on the cheaper stock. Plan based on production flow, as the up-front cost of an additional head will more than pay for itself by reducing downtime during label changeovers if you’re running at high speeds.”
Williams says that companies should take numerous factors into account before making a weighing equipment purchase. “These factors include, but are not limited to, robustness of design, assurance that the equipment will provide the functional performance required of it and that the complexity of the equipment does not exceed the capabilities of the maintenance staff.” From a food safety standpoint, the equipment needs to be easily accessible for both the sanitation and maintenance crews. He also recommends that prospective buyers put together an evaluation on the total cost of ownership, or how much the equipment is going to cost to operate.
Once a scale or other piece of weighing equipment has been installed, care must be taken to ensure that it maintains its accuracy and performance. “Regular maintenance programs augmented by periodic inspection and performance verification testing by the manufacturer will keep the equipment running to its designed specifications,” Thomas says. “Visits by the manufacturer are also an ideal time for refresher training sessions with maintenance personnel and line operators so they are current on the best practices to get the most performance out of their checkweighers.”
Gainco has recently introduced its AccuFill Quad Batching System with AutoCount. The system is able to collect and batch up to four products and interface with downstream packing systems. The machine can also bag to specific weight ranges or to fixed product count using the AutoCount technology.
Barr says that Heat and Control has numerous new products, including Ishida’s Fresh Poultry Weigher. Other products include Ishida X-ray systems and CEIA metal detectors as well as product handling equipment.
Bizerba’s newest weighing system incorporates an adjustable belt that can be set flat or moved into variable “V” positions to cradle and stabilize irregular-shaped packages. Stability during weighing leads to greater accuracy and speed, which in turn leads to higher profits, Saje says.
OCS Checkweighers has recently launched a new machine for a heavy washdown environment, the HC-WD. Additionally, the company has followed the market trend for compact machine combinations with its end-of-line inspection combination, consisting of an inkjet printer, an inspection system and a checkweigher.
Mettler-Toledo Hi-Speed has developed the XS Checkweigher Controller, with a 15-inch touchscreen display that is rugged enough to meet IP60K protection requirements, closely mirroring many customer cleaning routines. All product set-up parameters, including belt speed and reject timers, are stored in memory. The XS is used in the X3 Standard checkweigher, featuring full IP69K protection, hygienic construction and EMFR high-accuracy weighing technology.