Lareka recently won the Additive World Design for Additive Manufacturing Challenge 2017. The Dutch company did so by redesigning the Sealer Arm of a packaging machine for chocolate bars.
According to the jury, the redesigned and 3D printed sealer arm "demonstrates a successful combination of substantial quality improvement in chocolate packaging through better temperature control and a reduction of 50 parts". "The professionals from the Chocolate Shock Prevention Team at Lareka Confectionery (Netherlands) clearly show how the benefits of additive manufacturing can be exploited by creating a lighter and stiffer 'sealer arm' that can be made cheaper in smaller batches with improved functionality."
Less thermal damage
Lareka, which specialises in the overhaul and new construction of machines, focused on what head of engineering Wim Caris calls "the Mercedes among packaging machines" for this project. "It's a good machine, which uses a heating element to seal. But when heat gets that close to chocolate, sometimes it melts and you get damage. Maybe not seen by the consumer but we see it, and so does the producer. Making chocolate is a very precise process which is done by tempering. This ensures that the chocolate cools down properly, leaving nice shiny chocolate. This is done very precisely by machines at a temperature between 28 and 38 degrees. And then comes a packaging machine sealing at 140 degrees. That's a waste. We felt it was a challenge to come up with a better solution for this."
Lareka's specialists tried all kinds of things; induction, ultrasonic and other techniques. In the end, they still ended up with the heating element. "We needed to get the 140 degrees away from the chocolate. To cool it properly, however, you have to make a complicated thing. That's when we came up with the idea of 3D printing. In the end, this allowed us to omit over 50 parts. So a huge saving in assembly."
26 degrees
As there is a lot of (indirect) contact with food, the engineers chose stainless steel. The new sealing bar has integrated ventilation with cooling ribs. The holder keeps heat to a minimum. With Lareka's 3D heat machine, chocolate could be packed at a temperature of 26 degrees.
According to Wim Caris, the fact that the jury chose the sealer arm as the winner is partly due to the fact that the part they print is used directly in production. "Normally this is used for a prototype, but we just use the part to be printed. With the small serious ones we make, that's always interesting." Meanwhile, the company is working on improvements and has also started working on plastic printing. "With the competition, we won a plastic printer. We have already made products from that too. We don't stand still."
Student
The winner in the student category of the Additive Manufacturing Challenge was Cassidy Silbernagel from the University of Nottingham. With his new design for a carburettor for an internal combustion engine, Cassidy wanted to realise an assembly of moving parts without 'normal' assembly. It is very lightweight, has thin walls and self-supporting grids. It is the second time Silbernagel has won the competition. "This year's entries showed us more than just topology optimisation or lightweight design. Designers now have a broader view of design for additive manufacturing. They have looked very closely for improvements in their designs to eliminate manufacturing complexity and to minimise manufacturing, assembly or logistics costs. Increasingly, we see a combination of these factors coming together in the design. This underlines that industrial additive manufacturing is maturing."
By: Kelly Bakker
Source photos: Additive Industries
