Food Safe Additive Manufacturing in Välimeren Herkut

"We are now able to adapt to customers’ needs in a way that nobody else can.”

Petri Klemetti
CEO,Välimeren Herkut
 

3D printing to reduce machine downtime in food production

In food production, there are many areas in which the design freedoms and fast, on-demand production aspect of additive manufacturing (3D printing) are extremely appealing.  In production lines, even the most advanced or expensive machines need to be adapted for use after arrival on the factory floor.  Additive manufacturing can be utilized to create the necessary parts for the adaptation process, or alternatively used for rapid prototyping and testing of parts that will eventually be manufactured with traditional subtractive methods.  In addition, specialized spare parts are extremely expensive, may have long lead times, and in many cases, producers are reluctant to take orders.  Additive manufacturing can again be used to create temporary or permanent replacements for such spare parts in order to reduce machine downtimes and save money.

Modifying existing machine utilizing 3D printing

Etteplan has extensive knowledge and experience with the design and manufacture of 3D printed components – including for food contact materials.  Etteplan and Välimeren Herkut worked together to identify three cases where additive manufacturing would have immediate impact by allowing new product offerings to meet customer demands. 

The first case involved modifying an existing machine, in this case a carousel-style sealing machine, for a new production line.  Välimeren Herkut received an order request from one customer for a product in a small round cup with a plastic, easy-to-remove seal.  The order was so large that hand-sealing the product was not feasible.  The cost of a new sealing machine was prohibitively expensive, so the only alternative would be to update the carousel (rotating disc) of the machine.  With the traditional manufacturing approach, Välimeren Herkut was looking at a time-consuming and costly project. 

Case 1: Sealing machine carousel plate and original cup (square) and new cup (round)

Spare part replacement and modification

The second case studied could be considered a spare part replacement and modification.  The part was a simple nozzle used in a machine for packaging small sachets with salad dressing and other sauces.  After the measured volume of sauce flows through the nozzle, the machine seals sachet.  Thus it is imperative that the nozzle does not drip, otherwise the seal would be compromised and the product ruined.  The center diameter of the nozzle needs to be matched carefully with the sauce in order to achieve the no-drip requirement (i.e. thicker sauces need a wider nozzle), but testing is required to determine the correct size.  The machine at Välimeren Herkut had only one nozzle size, and thus the range of products that could be packaged with it was limited.

Case 2: Machine for packaging sauces and dressing in individual sachets; one example sachet; original nozzle

The third case investigated falls under the rapid prototyping category.  Again customer demand spurred the need for modifying an existing machine, in this case one that was used to package salad dressings.  A new product was requested that requires a larger dosing volume.  A new pump and associated parts would cost on the order of 40k€.

Case 3: Components for dosing in machine packaging salad dressings and similar

Three unique solutions to meet customer needs

Three unique solutions were created for the Välimeren Herkut cases studied.  In case 1, an AM design engineer created a clever solution that allowed for the fast and relatively cheap modification of the sealing machine carousel plate.  Snap-fit cup adapters were designed and created by selective laser sintering (SLS) of PA2200 powder which is certified as being safe for food contact.  The cup adapters were made in a way that did not require modification of the carousel plate at all, meaning that the same plate could be used for either cup size, and in fact the cup adapters could be easily modified to meet future customer needs as well.  The impact of this modification was immediate as Välimeren Herkut was then able to accept an order for 500,000 pieces using the small round cups.

Case 1 sealing machine solution: 3D printed snap-fit cup adapters that are safe for food contact

For the 2nd case, a parametric design of the no-drip nozzles was created.  Nozzles in eight sizes were 3D printed.  In order to avoid creating hard-to clean regions where food could get stuck, instead of engraving the size of each nozzle within the parts the nozzles were printed in different colors so that size could be easily identified.  In addition, because these parts were in constant and direct food contact, research was done related to potential food safe surface coatings and treatments.  The SLS printed parts suffer from a surface roughness that is too great for continued food contact due to potential for bacteria buildup.  At least one surface treatment was found that could reduce the surface roughness to levels recommended for stainless steel surfaces in contact with food.  Furthermore, due to the low cost of the printed nozzles, they could also be used for limited time without the surface treatment and then replaced.  Alternatively, the printed nozzles could simply be used as prototypes for matching new sauces or dressings with correct nozzle size before producing the optimized nozzle with traditional methods.

Case 2 no-drip nozzle solution: 3D printed parametric nozzle set, color coded by size and safe for food contact

In the 3rd case, the cylinder and piston of the dosing machine were redesigned for increased dosing volume.  The parts were 3D printed in the same food safe plastic material and installed in the dosing machine.  Tests were carried out to ensure that the existing pump could handle the new dosing volume, and then the new component designs were passed along for creation with traditional manufacturing techniques.  The design work, printing of the prototypes, testing, and creation of the final parts cost only a small fraction of what a new pump would cost, and once again new customer requests could be met.

Case 3 dosing solution – 3D printed piston and cylinder to test larger dosing volume with existing pump

Throughout the course of this project, two Etteplan AMO services were utilized: AM engineering (adaption/design for AM) and AM purchasing support.  Having an AM design expert involved in the work ensures that maximum benefits could quickly be gained from the geometric freedoms offered by AM.  The AM purchasing support meant that Välimeren Herkut gained information about AM service bureaus printing materials that are safe for food contact, had a clear overview of available surface coatings and treatments for food contact, as well as several cost-competitive offers for printing the needed parts.

3D printing to enable agile solutions in the food industry

Additive manufacturing can be utilized in the food industry to enable agile solutions to modify production for new food products.  This might include modifying existing machines for new product lines, rapid prototyping to test new machinery design solutions, and spare part replacement or modification.  The Välimeren Herkut cases clearly show the immediate impact of being able to quickly adapt for new customer demands, with additive manufacturing solutions allowing them to accept new large orders.