Getting a good grip
Robotic stackers-unstackers keep pace with today’s faster lines, while automated storage and retrieval systems supply pans as needed.
BakingBusiness.com, August 1, 2013
by Shane Whitaker, Baking & Snack

Upset the pan cart, and you’ll create quite a commotion within a bakery. Bread and bun pans are heavy and often dangerous because they retain heat from the oven, which can burn those who have to work with them regularly.

Yet there is no reason to have employees moving or stacking and unstacking pans in today’s bakeries because this can all be automated. Baking pans often require a substantial investment for a company, and as such, they want to treat this asset with care and gentle handling.

Operator safety represents an important consideration for adding this equipment. “A pan management system relieves the operator of moving heavy pan carts, keeps them safely away from moving stacked pans and encloses the stacking and unstacking in guarded areas,” said Dennis Kauffman, North American sales manager, AMF Bakery Systems, Richmond, VA.

Handling larger, stronger pans

While virtually every bakery could benefit from an automated pan management system, Ken Mentch, sales engineer, Workhorse Automation, Oxford, PA, pointed out that those running with high throughput rates, multiple pan changeovers per shift or an extraordinary number of pan types and quantities would benefit the most.

“Some bakers have the misconception that these automated systems are complicated and difficult to maintain or keep running,” he said. “Workhorse’s latest systems are designed to be maintenance-friendly and very reliable for these applications.” Mr. Mentch noted that automated sytems are extremely efficient, requiring minimal operator intervention.

With increasing line speeds and heavier and ­larger pans, Frank Atcherberg, president of Capway Systems, York, PA, stated that pan handling systems must be designed to handle greater speeds and weight requirements.

Today’s faster line speeds are pushing the limits of conventional stacking and unstacking, added John Keane, executive product manager, packaging and automation, AMF. Thus, handling multiple pans at once has an appeal in minimizing the impact automated systems have on them.

Bun bakers commonly are using 40- or 48-count sizes that are larger and heavier than can be handled by one operator manually, and heavy six-strap bread pans are common only in automated systems.

Pans can be constructed in varying strengths. “Lighter pans are often designed for manual use to limit the ergonomic impacts to the operator,” Mr. Keane said. “Heavier pans have features and a construction that helps maintain the pan’s shape when run in an automated system. These differences become obvious when pans designed for a manual system are run in an automated system.”

Bakeries can be unaware they have space for a pan handling system. “The Kaak Group is increasingly discussing the options of placing the pan handling system above existing ovens, on a mezzanine floor above existing lines or in a storage area away from the main production hall,” said Ken Hagedorn, vice-president and partner, Nagele, Inc. Bakery Systems, Alsip, IL, the US representative for the Kaak Group, Terborg, The Netherlands. “All these options give the opportunity to add a pan handling system within an already full production area without affecting the overall capacity of the bakery.”

Robots reduce maintenance

Gantry stacker-unstackers from Workhorse represent the company’s latest advances in pan and lid handling equipment. “The new robotic stacker/unstacker is designed to provide a gentle, accurate high-speed stacking system for all bakery and pan and lid types,” Mr. Mentch said. “These systems provide longer pan life, higher production rates, less pan and lid jams and quieter working environments.”

The Allen-Bradley intuitive control scheme managing the pan system is user- and maintenance-friendly. The stacker-unstacker is a part of Workhorse’s automatic pan and lid management systems that also include automated storage and retrieval systems, which can be either single or multi-level depending on the floor space available.

The storage and retrieval system continually serves the robots by retrieving the pan and lid type requested from storage simultaneously as it stores the pans and lids coming off of the production line. “These systems are integrated together, requiring no dedicated plant personnel to continually supply pans into and out of the production line,” Mr. Mentch noted.

AMF designed its new PALSUS unit (Pan and Lid Stacker-Unstacker), which uses four-axis robots, to handle increased pan rates as well as larger pan sizes. “It handles multiple pans or lids at one time, resulting in quieter, gentler pan handling,” Mr. Keane said. Its design contains 70% fewer moving parts than conventional magnetic units, thus significantly reducing maintenance.  

The Capway Robocap pan system features a gantry-style robot that stacks, unstacks, stores and retrieves pans within the same unit. “The large gripper allows multiple pans to be picked up at one time, therefore, reducing the cycles the robot has to perform,” Mr. Atcherberg said. “No pan trucks are required because the pans are stored within the system. This allows higher stacks because they do not have to be moved after stacking, so less floor space is required.”

By stacking and unstacking the pans vertically, he observed, the pans are handled gently, and the coatings on the pans are not damaged by the process, therefore, extending pan and pan coating life. “The greatest benefit is that the Robocap system automatically meters the line,” Mr. Atcherberg explained. “It adds and removes pans based on the line requirements. It allows easy changeovers without the need to move heavy pan trucks around and the possibility for them to fall over and someone to get hurt.”

Regulating the number of pans in a line ensures bakeries have the correct number of pans for the hourly capacity and desired throughputs rates. “The pan management system can also be linked to manage the life of the pans by automatically detecting and removing those pans from the system for recoating,” Mr. Hagedorn said. “These are automatically stacked on pallets by the storage crane and are then easily removed by a forklift.”

Calculating the return

During the past few years, the Kaak Group systematically put every design, concept and fabrication process through several stages to a new level of hygiene. “For example, our lidders, delidders and depanners are now manufactured with only closed profiles, and all angles and inclines have been modified to prevent as much as possible dust and water lying or remaining on them,” said Ashley Morris, area sales manager, USA, for the Kaak Group.

“Sensors, regardless of where they are, have been given a hygienically safe, standardized and, thus, easily exchangeable fastening,” he continued. “This hygienic design exercise has gone into the smallest detail. An example of this fact is that pressure and dimensions of all components, even hoses and valves, have been checked and, in case of doubt, improved.”

Also, a new depanner design from the Kaak Group enables placement of almost all components alongside the line, so nothing can drop or drip onto the product. The only things positioned above the production line now are the head and the needles. There’s an added benefit. “The head is interchangeable and can even be changed to a suction depanner,” Mr. Morris explained.

When determining the return on investment (ROI) of pan handling equipment, bakers have to count factors such as operator safety, floor space, number of pan sets and daily changeovers, line speeds and operator salaries, Mr. Kauffman said, noting that AMF has spreadsheets available to help with this analysis.

Mr. Mentch noted that the ROI comes from reducing the number of dedicated operators, saving floor space through the use of multi-level storage and lengthening pan life through the gentle handling, all of which provide a substantial savings to bakeries.