Alcan packaging company uses robots to automate stacking

Alcan Packaging's work in Cayey, Puerto Rico, produces bottles for medical supplies and cosmetics. Alcan Packaging, formerly the Wheaton Plastics Factory, converted some of its molding machines from Cayey to bottles and lids and sold them to Procter & Gamble for packaging of Noxzema and Olay skin care products.

Alcan recently bought a system designed and customized by the supplier Schneider Packaging Equipment. The system can smoothly transport the bottles from the molding machine to the automatic control area and stack their stacks by an automatic device. The stack pallets were then transferred to a reciprocating shuttle car made by Schneider and transported by a skip to the new stretch film packaging machine manufactured by ITW Muller.

The Schneider Integrated System, which started operating at the beginning of last year, has reduced the number of employees for the plant by 8 employees, which also partially proves its cost-saving features.

Both Alcan Packaging and Procter & Gamble want to go further in Cayey's stacking process. Noó Gonzálz, the plant's technical support manager, said that the process used to require two large palletizers. Although the stacking was done automatically, the assessment found that there were too many workers.

“The two palletizers pushed the bottles onto a pallet, one layer at a time,” he said. “When one layer has been placed on the pallet, the position will be reduced. A worker puts a skateboard on it. Then put the next layer of bottle on the slide and continue until the pallet is full,” recalls Gonzálz. “There was a need for an operator to do this. The skateboard had to be manually placed on each floor. When the number of bottles is too large, especially when the weight is light, if the system moves incorrectly, the bottle can easily fall down."

The operation of the Alcan palletizing system is divided into two shifts of 12 hours per shift, 7 days per week. It receives the output from 4 machines in the previous process. Two injection blow molding machines produced blue and white polyethylene bottles for Noxzema, measuring 2.5 ounces, 6 ounces, 10.75 ounces, and 14 ounces. Two injection molding machines produce polypropylene bottles for Olay products with dimensions of 50ml, 60ml, and 100ml. The colors are natural or gray.

In June, the fifth production line of the Schneider system started working. The injection-molded PP Magnolia bottle cap was fixed on a plastic pallet and was output from the production line (the Noxzema cap was not included).

Seeking a solution

Prior to purchasing the automatic operating system, Alcan invited three major suppliers to bid for the project. Gonzálz said: "Most suppliers tell us that 'we can only provide certain types of products, and Others cannot.'" Only after visiting Schneider did they get a satisfactory answer. Ranzel Benitez, General Manager of Gonzálz and Cayey Plant, and Engineers Glenn Estad and Dan Lock jointly decided to purchase the system.

Gonzálz said that he discovered the Schneider Integrated System through Motoman. “In my previous job, I was exposed to Motoman's automation equipment for seven years,” he said. “It's incredibly good work.”

According to Gonzálz, Procter & Gamble did not specify this equipment. “We just let them know what we are doing,” he said. “We contacted them and told them we bought this equipment.”

Although there are some differences in the way the forming equipment transports the bottles, the overall process of stacking the bottles by the four forming machines is the same.

“When the Olay bottle comes out of the two machines, it goes directly into the lift belt,” explained Gonzálz. After the two molding machines are discharged, they go directly to a flat table chain transport area. When a group of bottles (16 for each mold production) is delivered to this area, the conveyor belt stops temporarily.

Then, a servo drive system with bearings lifts the conveyor belt area to a certain height, opens the conveyor belt, and conveys the bottles along the conveyor belts installed on the wall and the ground. After the conveyance is completed, the conveyor belt drops to the original position. According to Schneider, this situation repeats every 30 seconds. Due to the limited space in the factory, it is necessary to upgrade the conveyor belt.

The bottle was sent to a cooling channel for 30 seconds. This is especially important for thick-walled bottles because they can only be touched after processing. After exiting the cooling channel, the bottles are conveyed to the automatic stacking area. Noxzema bottles are handled slightly differently. When the bottle comes out of the forming machine, it enters the conveyor belt above the ground level 3'. They rise slightly below the height of the Magnolia oil bottle and are fed into the automatic palletizing zone via the S-shaped conveyor belt, rather than through the lifting device as in Olay, into the automatic palletizing zone.

Stacking

The four bottle production lines are output in a single row from the cooling channels and then enter a warehouse through a wall. The warehouse includes a fully enclosed automatic palletizing area. For operational safety, the area is also fenced and measures approximately 30'x70'. The stacking system has also been programmed, and Alcan's operators can switch back and forth between various sizes of bottles and tray covers. This is handled through an Allen-Bradley Control Logix PLC control system with an operator interface provided by Rockwell Automation.

The bottle stays in four lanes until the correct stacking number is discharged. The number varies according to the type and size of the bottle. The bottles on each floor are staggered, and there may be 16 bottles in a row, 15 in the next row, 16 in the next row, and so on. This helps stabilize the bottles in each layer.

In order to lift the bottle, the Motoman robot chose the 6-tool head. Each end is used for bottles of different diameters. The control system will remind the robot to rotate to the proper tool head, then the vacuum cup on the tool head will contain 16 bottles from the conveyor belt.

The automatic arm moves along the arc and the No. 1 conveyor belt picks up the bottle and puts it into the No. 1 crane. Bottles on the No. 2 conveyor belt are put into the No. 2 machine, and so on.

The Olay cover placed in a 360 degree plastic tray is transported from the fifth line to the automatic palletizing area. The fifth line is in the middle of the four bottle production lines.

When necessary, the automatic boom can lift wooden pallets and skateboards. The skateboarding station is next to two Olay bottle production lines, and the palletizing station is located next to two Noxzema bottle production lines.

When a pallet is full, it is exported to the traction chain pallet conveyor. The reciprocating shuttle car of the Schneider system travels along a path that is perpendicular to the four pallet conveyor output conveyors. The skips on the polyurethane wheels move back and forth along the tracks, the rails are bolted to the ground, and the skip slides to a suitable pallet position to receive a full pallet. When the pallet is placed on the skip, it is transported to the ITW Muller Octopus extension wrapper.

“The packaging machine is turning along a fixed load,” Gonz噇ez said. “The machine is working very well.” And it's a moderate price compared to other packaging machines that the company considers. Packaged goods are transported by forklift into the designated area of ​​the warehouse.

Since the system's operation, Gonzálz said, “So far we don't need extra services. From the beginning, Schneider's equipment left a deep impression on me and now we rely on it every day”.

This automated system not only saves labor costs, it avoids the loss of the bottle during the previous palletizing process, and it also saves valuable space for our factory. "The automatic palletizing area does not occupy much space, as does the space occupied by the two large-sized cranes we used before," Gonzálz said. He also mentioned that although the automation equipment is specifically designed for bottles/covers, it is flexible enough to be used for different purposes. Gonzálz expects the investment return on the system to be "just a little more than two years".