Masterfoods is a privately owned company that produces snack food, pet care and human food and operates on all continents. Well-known Masterfoods brand names include Mars, Bounty, Snickers,
Twix, M&M’s, Uncle Ben’s, and Whiskas and Pedigree.

In order to best meet the requirements for quality and performance, Masterfoods’ engineers will improve existing machines or sometimes develop their own machines. This development process is ongoing and involves close cooperation with both suppliers and the actual operators of the production machinery. One of the most commonly used machines by Masterfoods is a flow wrapper, used for the primary packaging of bars.

The challenge
A flow wrapper takes the chocolate-covered bars and wraps them in their distinctive branded wrapper. The same product can be made in different sizes, ranging from miniature to king size; some packages contain not just one but two or three bars. Different product formats not only require different packaging film sizes but, even more importantly, different machine configurations.

For all packaging “recipes”, as they are called at Masterfoods, speed profiles have to be adjusted for all of the servo motors and frequency inverters. A typical flow wrapper has several separate axes and, depending on the wrapping recipe, can process hundreds of snacks per minute. Quality is very important at every stage; it is unacceptable, for example, if the brand label on the wrappers appear out of place.

Vital to the machine speed, reliability, flexibility and ease of use for the operator is the choice of control system and architecture. Masterfoods control engineer Jos Wubben explains that on a recent project a major improvement was made through the replacement of the Flowwrapper control by a Rockwell Automation solution based on the ControlLogix platform.

Not only did Masterfoods realize considerable savings, but also the Rockwell Automation Integrated Architecture solution delivers many technical benefits. Following this implementation, Masterfoods decided to standardize on Rockwell Automation on all of its future wrapping machines.

The transition from one system to another has quite an impact, and transition costs are usually quite substantial. However, because the machine manufacturers recognized the status of Rockwell Automation as a worldwide supplier of control solutions, and also because of the support they received from Rockwell, the impact of transition has been minimized.

The solution
“To control a flow wrapper, you need to process a lot of signals very rapidly,” Wubben explains. “One of the advantages of the ControlLogix unit is its very fast CPU. In the previous control system, we had to use two controllers and very specific hardware to capture fast interrupt signals. Now, the ControlLogix unit does it all with standard functionality, and no wiring or programming is required to let multiple parts communicate. This, of course, also means less space needed and a less complex system in general.”

But the major advantage, he says, is the scale of integration that Rockwell Automation was able to offer. Motion controllers and frequency inverters, for example, are driven by modular local networks and controlled through the Logix operating system. All these granular components can be programmed through a personal computer.

“We use the Rockwell integrated development environment,” Wubben adds, “and we have been able to port our own software. When the operator of a flow wrapper needs to change the configuration because another product variation is to be packaged, he or she can now just select a ‘wrapping recipe’ from the menu. A key element in this is the tight integration of controls, motion and drives. Mechanical configuration is also much easier. Formerly, we had to swap machine parts if we wanted to process different formats, but the system is now much more flexible. It’s also easier to integrate the wrapping process within the overall chain of production and secondary packaging.”

Of course, moving to another control system was a major step for Masterfoods. There was a learning curve, but Rockwell Automation provided the necessary support. This support is also provided to all OEMs and has been a key issue for Masterfoods in standardizing on Rockwell Automation for all OEM controls.

It also helped that Rockwell Automation is a worldwide supplier of these solutions. OEM adaptations might well be a major selling point to prospective customers of the machine manufacturer.

The results
The collaboration between Masterfoods and Rockwell Automation has been successful and will be continued and expanded. The OEMs have been eager to support the transition because of support offered by Rockwell Automation, including training. Other positive factors included low costs and the added value of being able to deliver Rockwell Automation solutions on its machines.

The transition to Rockwell Automation has been very cost-effective for Masterfoods. Overall costs of the systems have dropped thanks to 7 percent savings on hardware costs and 5 percent savings on labor. For example, because less wiring was needed inside the control unit cabinet, two person-days out of 10 were saved on a typical installation. Another four person-days out of 20 were saved on the wiring of the machine itself. Testing and tuning were also shortened, by two person-days out of 10. Moreover, instead of using two separate controllers, control is now integrated in one rack, with no extra wiring or programming, resulting in less complexity and reduced sources of problems. The Rockwell integrated architecture makes it much easier to configure the flow wrapper.

The integrated, modular architecture facilitates programming and implementation of wrapping recipes, which has a positive effect on machine operating costs. Finally, the Rockwell solution facilitates integration within the Masterfoods production line, of which the Flow Wrapper is a part.

This article was provided by Rockwell Automation. To learn more, visit www.ra.rockwell.com.