- Nearly obsolete control system kept flour mill managers scrambling to find replacement parts, while managing production and industrial safety risks complicated by a lack of visibility into the multi-stage process.
- Integrated Architecture – Information-enabled Allen-Bradley ControlLogix® controllers and FactoryTalk® View Site Edition HMI control and monitor operations across the mill, giving employees access to critical parameters.
- State-of-the-Art System Design, Deployment – Kice Automation, a Solution Partner within the Rockwell Automation PartnerNetwork™ program, designed and deployed the solution, while keeping production up and running during the changeover.
- Increased Uptime, Output – Downtime decreased by minimum of 5 percent; yields consistently closer to daily targets.
- Unprecedented monitoring, control capabilities – Centralized data collection, visible at multiple workstations, enables operators to make more accurate process adjustments, and more swiftly respond to alarms.
Advanced Rockwell Automation infrastructure and Kice Automation system design boost mill’s uptime, output, reputation
From cookies and cakes to pretzels and pastries, many of the snack foods enjoyed by consumers along the Eastern Seaboard contain flour milled in the tiny town of Mount Joy, Pennsylvania. Here, the Wilkins Rogers Mills company transforms soft wheat into the key ingredient used by commercial bakers to satisfy America’s sweet and salty cravings.
The Mount Joy mill is one of three plants operated by Wilkins Rogers, whose history dates backs to 1913, when Howard Wilkins and Samuel Rogers purchased a flour mill in Washington, D.C. Aside from the fundamental process of grinding grain and sifting out particles to form a pure powder, today’s industrial flour mills bear little resemblance to their ancestors. Automated processes have transformed the old back-breaking, hand-blistering manual labor required for centuries to extract flour from wheat.
The Mount Joy plant operates two milling units, along with extensive equipment for grain transfer, flour handling, packaging, and bulk shipping. Each milling unit employs massive rollers that separate the wheat’s hard outer coating from the floury inner endosperm. Then comes the process of sieving, sifting and regrinding the flour into different grades, depending on the needs of the bakers who buy it.
The Mount Joy plant can produce up to 700,000 pounds of flour day. But meeting that target became more and more challenging in recent years because of the mill’s outdated control system.
SYSTEM SUPPORT, PARTS AVAILABILITY
The mill’s programmable logic controller (PLC) was vintage1990s. To make changes to the program, operators had to use a laptop computer running Windows 95. Spare parts and support were nearly non-existent and the spare parts that were available were used or remanufactured with no warranties.
Locating replacement parts created even more problems. Operators were constantly searching for parts to keep on hand in case of a shut down. However, the reliability of those spare parts was spotty at best.
The plant’s single human-machine interface (HMI) was also very basic in what was provided for operators in charge of the equipment.
“The computer screen was very old and didn’t give us a good visual representation of the process,” Black said. “Bigger picture, we had difficulty monitoring our plant’s performance and measuring output accurately.”
“The person who installed the control system in the ‘90s had difficulty supporting it anymore because of the age of the technology,” said Aaron Black, Director of Operations at Wilkins-Rogers.
The question for senior management wasn’t if they needed to invest in new control technology. The question was when. That answer arrived in mid-2015.
GAINS IN EFFICIENCY, SAFETY
Black and his operations team turned to Kice Automation, well-known for its expertise in the flour-milling business. Wilkins Rogers had consulted with Kice on several smaller projects in its mills.
“No one checked off all the boxes like Kice did,” Black said. “We were well aware of their advanced knowledge and attention to detail.”
Kice’s advanced knowledge in milling processes– including their experience as a Solution Partner within the Rockwell Automation PartnerNetwork™ program -- helped convince Black and his team that instead of a mere replacement, they should implement an entirely new control infrastructure for the Mount Joy facility.
“The Mount Joy team had a wish list of capabilities that couldn’t be realized with just a PLC upgrade,” said Syed Ashraf, vice president of automation/electrical at Kice.
Deploying new sensors for added worker safety was near the top of that wish list.
“We care about employee safety first and foremost,” Black explained. “With new sensors on equipment tied into the control system, we not only enhanced the safety but reduced the chances of equipment failure.”
The Kice team also helped Black meet another key goal: systematically replacing the obsolete control system with little or no downtime in production. That change-over feat required more than six months of careful planning and collaboration between plant personnel and Kice engineers.
“When we were ready to switch out the PLC, we were fortunate that our existing Motor Control Centers (MCCs) had hand-off auto capabilities,” Black said. “That meant we could run all the equipment manually, allowing time for final wiring in the new panels.”
The centerpiece of the state-of-the-art infrastructure is the Logix Control Platform with a distributed I/O architecture. The Rockwell Automation solution also included redundant HMI servers, allowing for both production back-up and spare capacity for future applications.
Four new workstations were strategically installed in the facility, allowing operators to monitor real-time production data using the FactoryTalk® View Site Edition (SE), supervisory-level HMI software from Rockwell Automation.
“For the first time, information on wheat extraction, flour yields and peak-production amounts all feeds into highly visual display, allowing operators to accurately optimize the process,” Black explained. “And if we’re not meeting our targets on a daily or trending basis, we can track what’s happening to find out why. Our new insights also are invaluable for the maintenance folks.”
Multiple workstations and equipment sensors have contributed to both uptime and worker safety.
“Alarms can pause or even suspend the milling process,” Black said. “Now, if a sensor sets off an alarm, an operator can simply go to the nearest workstation, acknowledge it and take care of it. No more running around to try to figure out the problem.”
The remote support provided by Kice – based in Kansas – is another boon to Black’s peace of mind. “An engineer in Wichita can jump on our system in a minute, see what’s happening and help us through a solution,” he said. “Kice deserves a lot of credit for the work they put in and their continued support to make this a successful project.”
NEW SYSTEM CAPABILITIES
Proof of the new system’s success: Downtime has decreased, according to Black “With the Rockwell Automation solution, we are maintaining our good yields and meeting our production targets – both things we can more accurately measure now,” he added.
Now that the Mount Joy mill’s new infrastructure is in place, Black and his team are consulting with Kice about how to further leverage the system’s advanced capabilities.
“We have the potential to monitor a lot more than just pieces of equipment,” Black said. “I have a list of enhancements that we can bolt on.”
Topping the list: automated energy monitoring. Power usage is the mill’s second-largest operating cost, after personnel. Industrial strategies for controlling power costs – especially during peak demand periods – must be reported using accurate energy-use data.
“The future holds a lot of promise with our new system,” said Black, who added that the Kice-designed solution, built on Rockwell Automation technology, will be “the standard going forward for our sister facilities.”
The results mentioned above are specific Rogers Wilkins Mill’s use of Rockwell Automation products deployed by Kice Automation in conjunction with other products. Specific results may vary for other customers.
ControlLogix, FactoryTalk and PartnerNetwork are trademarks of Rockwell Automation Inc.