Going Green: What That Means for Case Packing Machinery

A few small changes to case forming, packing, and palletizing can go a long way in preserving the environmental and economic impact of recycled materials. Image courtesy of ProMach.

Recyclable Materials Require a Few Modifications

By Mike Grinager, VP of Technology at Brenton and Sander Smith, Product Manager at Wexxar Bel

Using recycled cardboard material in cases is an attractive option for many manufacturers. One major benefit is the savings, as flats formed from recycled content can be about 30% cheaper than those made from new materials. There’s also the environmental impact that of  recycled materials, which matters to many consumers.

Recycled materials can be a positive change in any line. However, some line operators are unaware of the modifications that must be made to accommodate them. A few small changes to case forming, packing, and palletizing can go a long way in preserving the environmental and economic impact that recycled materials can have.

Reduce, Reuse, Reinforce

When cardboard is new, the paper fibers it’s made up of are long, making it strong and rigid. On the packaging line, this allows it to pop into form quickly and accurately with nearly any case assembling method. Every time the material is recycled, the fibers are broken and become shorter. This makes the material softer and more porous, often so much so that most people can tell the difference between virgin and recycled cardboard by touch. In some areas of the world where cardboard is recycled infinite times, boxes can even be described as having a “peach fuzz” feel to them.

Wexxar Bel’s pin and dome mechanical case opening system provides predictable and repeatable case erection. Image courtesy of Wexxar Bel.

In addition to changing the texture of the box, recycled cardboard has an impact on how the flats need to be handled. Recycled flats are significantly less rigid, requiring more care when being manipulated into the formed box to avoid damage. The increase in pore size and quantity also makes the material more susceptible to warping and moisture saturation during storage and transit, which can damage flat inventory or even packaged product.

One way to boost the integrity of these packages is by strategic formation of the flats themselves. Corrugated cardboard is built from three pieces of material: an inner liner, the corrugated material in the middle and the outer board. Using recycled material for the corrugated piece and new cardboard for the inner and outer board can help balance sustainability with strength.

Another method that some case manufacturers will use is a combination of recycled and new material in the cardboard forming each layer. If the customer is looking for 100% recycled material, this can be accomplished by reinforcing the outer layer with a double wall to improve rigidity and the final box’s integrity.

When customers are selecting their corrugate,  they need to consider both the quantity and placement of any recycled material, and must be conscious of how the box will get to the packaging line and ultimately out to market. Conditions such as humidity and travel over rough roads are hard on any cardboard, and the impact is felt much more on recycled content. Manufacturers sending their products through tougher conditions may need to be more selective in how they use recycled material.

Forming That Fits

Accommodations for recycled materials must also be implemented in the packaging process. The forming method, for instance, needs to run in a way that accounts for the softer material. Many packaging operations that incorporate recycled cardboard will do the case forming and packing by hand to maintain more control. This is a good option for proper material management; however, it limits the possible throughput of the line. Ongoing staffing shortages also complicate this method, with workers for assembly tasks like this being increasingly difficult to come by.

A vacuum style venturi gripper with a foam pad can handle corrugated cases, slip sheets and pallets, and covers a larger area than a vacuum cup system, ensuring the tops of the cases remain flat during movement. Image courtesy of Brenton Engineering.

Moving to automation in this stage of the end-of-line packaging process is a great way to accommodate future growth. However, if recycled materials are currently being used in the manual process, or if the operation may incorporate them in the future, the case former needs to be able to work with the softer flats. Vacuum systems may fall short in this area, as recycled content is less likely to snap into place. This method is particularly unforgiving and can lead to flats being warped from forced opening, resulting in stoppages on the line.

Other options have a greater margin for uncooperative material. The Pin and Dome system is an alternative method that uses two hardened steel pins and a raised steel dome. Cases are thrust upward, guiding the pins into the flutes of the corrugate and securely moving them into the proper position for packing or filling. By working with the access points provided by the corrugate, this technology guides boxes into shape, regardless of corrugate quality.

Proper Palletizing

Vacuum systems can also create issues in the palletizing phase of packaging recycled boxes. Operations using this material should prioritize other options, such as a clamp tool that does not rely on the structure of the box to properly function.

Before recycled cases leave the facility, operators should fortify the pallets for an additional layer of protection, especially if the products will be traveling through potentially hazardous conditions. Unfortunately, this cuts into some of the cost savings and environmental impact of selecting recycled cardboard, but it also reduces the risks to product integrity that can be heightened by this material.

Eco-friendly operation is an understandably popular initiative for companies to partake in, and bringing in recycled corrugate is a smart step on the way to reducing a business’s carbon footprint. Line operators just need to understand that switching from virgin cardboard to reused cardboard is not a simple substitution, and adjustments must be made to ensure that going green goes great.

About the Authors

Mike Grinager is the Vice President of Technology for Brenton, a ProMach brand. He can be reached at Mike.Grinager@promachbuilt.com; https://www.brentonengineering.com/