The food service industry operates under the strictest rules of hygiene mandated by the Food and Drug Administration (FDA). Food processing and packaging lines must be kept spotless, eliminating the possibility of bacterial growth and spoiling. At the same time, quality of product is paramount. Foods must taste their very best, and can never be mixed with improper ingredients. As well as the customer experience suffering, FDA rules forbid false labeling of any product. Whatever the label states must precisely reflect the contents.
So what do you do when you produce up to 30 different food items per day? With two to three shift changeovers and the factory running close to twenty hours a day, the cleanliness and integrity of the changeover process is crucial. This was the challenge facing Nestlé USA's L.J. Minor Plant in Cleveland, Ohio.
"Accommodating production changeovers is certainly a major hurdle," said project engineer Jeff Shiepe. "These lines are mission critical and we can't afford to ever have them suffer from unscheduled downtime."
To eliminate the risk of failure, Nestlé USA utilizes SafeTTouch 4X screens from Dolch Computer Systems of Fremont, California. These sealed stainless steel touch screen workstations are designed to repel bacteria and withstand demanding cleaning procedures.
"Previously, we used to suffer from problems due to accidental damage to machinery and screens," said Shiepe. "The Dolch screen is so durable that you can beat on it with a tool without hurting it in the slightest."
World's Largest Food Company
Nestlé S.A of Vevey Switzerland is the world's largest food company. While Nestlé chocolate is famous in its own right, the company is responsible for dozens of the most popular food brands on the market. In the USA, its seven divisions encompass beverages, confections and snacks, food services, nutrition, pet care and prepared foods.
Nestlé USA's over 8 billion in sales annually are accomplished via 17,300 employees working at 33 manufacturing facilities, 6 distribution centers and 17 sales offices around the country. These facilities produce such renowned brands as Nestlé, Carnation, Ortega, Toll House, Stouffer's, Minor's, Nescafe, Coffee-Mate, Libby's, Blackwell, Kerns, PowerBar, Buitoni, and Lean Cuisine.
The 120,000-square-foot L.J. Minor facility in Cleveland services some consumer needs but focuses on the commercial needs of restaurants and cafeterias. It specializes in bouillon-type pastes that are used as a base for soup and gravy, and as flavor enhancers. Over 600 items are cooked and processed before being routed via food pumps to Nestlé USA's packaging area. These pumps place exact quantities in containers prior to shipping.
The packaging area consists of a total of five packaging lines. It contains the food pumps, packaging machines and case packagers. Operators use two Dolch SafeTTouch 4X screens to monitor production and report data to management.
"Our packaging machines are our bread and butter," said Shiepe. "They are running constantly and output a high volume of goods.
Challenging Environment
Operations at the Cleveland plant are optimized to eliminate the losses that can easily mount up during changeover from one food item to another. A chicken base, for example, may be followed by the same chicken base with added MSG. In this example, the line would not require washing before packaging the product with the added MSG. But with 20 to 30 products handled in any given day, several thorough washes have to be done each shift, making downtime inevitable.
In keeping with its reputation for high standards, Nestlé USA hoses down its entire packaging line during a changeover to eradicate all bacteria and remove any trace of the previous food items. This wash must be strong enough to penetrate any and all nooks and crannies where food may be lodged or where microorganisms may multiply. Further, the cleaning solution is so caustic that operators wear protective clothing, masks and gloves.
Unfortunately, Nestlé USA's previous screens were not designed to operate in such a challenging environment. "Our old screens could not withstand the constant battering during washing or the volume of goods moving through the packaging lines," said Shiepe. "As well as the five and a half inch screen being too small, they lacked functionality and suffered due to leakage and condensation."
While these machines were built for a hardy setting, they suffered badly over time. One operator, for example, inadvertently knocked a whole in a screen. After several months of exposure to hot caustic washes, another touch screen required replacement. Nestlé USA also had to contend with serious moving parts issues. High impact and vibration sometimes caused bolts and moving parts to come loose. As a result, supervisors inspected all screens and machinery daily to safeguard the food packaging line.
The plant's old touchscreens, supplied by another major manufacturer connected to a Programmable Logic Controller (PLC). According to Shiepe, a PLC-based network without an adequate operator interface failed to provide plant floor staff and management with the information they required. Further, programming of the PLC to acquire the needed production information absorbed valuable time. End of shift reporting remained paper-based.
"The administrative burden at the end of each shift amounted to about five hours per day," said Shiepe. "Each operator filled out a form, handed it to a supervisor and then a day or two later someone else entered the information into the database. This made it both slow and difficult to track downtime."
Bulletproof Screens
Fortunately, Shiepe subscribed to an online automation newsletter and noticed that Dolch's range of durable touch screens came highly recommended. During an onsite demonstration, the representative impressed him by being unable to damage the screen despite his best efforts with a large screwdriver. Nestlé USA ordered the Dolch SafeTTouch 4X.
The SafeTTouch 4X is a completely sealed touch screen encased in heavy-gauge 304 stainless steel. It has been designed for continuous reliable performance in extreme NEMA 4X/IP 66 hose-down environments. Its airtight multi-sealing procedure protects the electronics from chemical cleaning sprays, solvents, water, grease, and other liquids used in the harsh Nestlé USA environment. The internal electronics are exposed to steady air circulation to maintain an optimum, uniform operating temperature to ensure long life and eliminate condensation.
"A minute of downtime runs up exorbitant costs, so we can't afford any unscheduled maintenance," said Shiepe. "All electronic and computer systems should be as bullet proof as these Dolch screens."
Traditional touch screens consist of some kind of coating or glass overlay. These surfaces are subject to scratching, damage and failure. Some types respond poorly to a gloved hand or other non-grounded stylus. The operator interface of the SafeTTouch 4X, on the other hand, features Dolch's EnhancedInfrared touch screen technology. These ruggedized screens are ideal interfaces for hazardous operating environments. EnhancedInfrared touch screens, use a matrix of invisible light beams to detect operator input and remain calibrated without drifting. As they don't depend on some kind of overlay, they are immune to cuts, scratches, or wear of the touch surface.
"You periodically have to replace resistive-type or pressure-sensitive screens," noted Shiepe. "But you never have to replace IR-based screens like the SafeTTouch 4X."
The SafeTTouch 4X also comes with a Dolch's RayFire fiber optic video and data transmission system. RayFire allows the Nestlé USA systems PC to be located off the plant floor in a climate-controlled room.
"The old system didn't give us much data about what was happening on the plant floor, how much downtime we were experiencing or the causes of it," said Shiepe. "The RayFire-enabled Dolch system allowed us to deploy a Windows-based application to our operators, which means that with a couple of touches, operators can enter an abundance of data, monitor the entire line and let management see what's happening in real time."
More On The Way Screen
Due to their excellent performance in one of the toughest plant floor environments around, Nestlé has decided to add more Dolch touch screens to the group it already owns. "After over two years of operation, we haven't had a single problem with any of our SafeTTouch 4X screens," said Shiepe. "End-of-shift administrative time has been reduced from 5 hours to a few minutes."
