FDA-compliant e-chains® in hygiene-sensitive mushroom-harvesting system

• What was needed: TH3 e-chain® and chainflex® cables (CF211.038 and CF210.UL.15.15.02), supplied ready-made as a complete pre-fitted readychain® package, drylin® W linear bearings
• Requirements: Cable guidance systems for an environment with high humidity and regular sterilization with 80°C hot steam. FDA conformity. Quick and easy installation. Extended maintenance intervals.
• Sector: Food industry
• Success for the customer: With the TH3, the harvesting system can be operated automatically without any incidents occurring in the cable guidance system. The e-chains® are FDA-compliant, resistant to aggressive cleaning agents and chemicals, and corrosion-free. The TH3 also works reliably even in high humidity.

The mushroom industry has traditionally struggled with a shortage of mushroom pickers who are needed for harvest work.
For this reason, Axis Technology and Development Ltd has developed a mushroom-harvesting system that can take over several process steps in the harvesting process.

As soon as the mushroom picker has selected the mushrooms from the growing bed, it places them on mushroom-holding fingers on a harvesting conveyor. The conveyor transports the mushrooms to a processing unit that cuts the mushroom stalk to the desired length. Depending on its size, the mushroom is then placed in one of six boxes. As soon as the carton reaches a predefined weight, it is ejected and then transferred to the dispatch area for wrapping and palletizing.

This process is on average three to four times faster than conventional mushroom harvesting. Or to express it in kg: while conventional harvesting methods can harvest around 21kg of mushrooms per hour, the system manages an average of 60 to 75kg.

Just like with any other automation system, the challenge in designing the system was choosing the components. Every movement and every mechanism must function perfectly to avoid time-consuming and expensive manual intervention by engineers. All of this had to be ensured under difficult environmental conditions: mushroom cultivation rooms use operating temperatures of 18 to 20°C, but the room and equipment are sterilized twice a month using 80°C steam. Due to the hygienically sensitive environment, products using FDA approved materials were also required to minimize the germ load and facilitate cleaning work.

Where things move, bearing technology and energy chains are often used. Axis used a special energy chain to fulfil the high hygiene standards in the system as well as drylin® W linear bearings.

Several blue TH3 FDA-compliant energy chains were suspended and guided cables on a travel of 3 meters each at a speed of 30 to 40mm per second. It wasn't just the space conditions in the facility that were critical. The TH3 was chosen due to the strict requirements for simplicity and speed of installation as well as the main focus: hygiene.

The energy chain has been specially developed for contact with food. The system's compliance with FDA regulations was crucial for the customer. The entire system is regularly washed and sterilized under hot steam. Not only does the energy chain have to withstand the environment permanently, it is also important that no parts fall into the processed product. If fragments of the material do drop off, the blue color of the material enables rapid optical detection before food is contaminated.

The hygienic design of the TH3 is evident at all points in the energy chain. For example, it has rounded corners and threadless connections to avoid dead spaces where dirt and germs could accumulate. The design of the energy chain also avoids overlapping surfaces, which prevents abrasion and material wear. The blue material is not only FDA-compliant, but also highly resistant to chemicals and aggressive cleaning agents.

The initial order for the TH3 energy chain comprised of 32 conveyor belts totaling 96 meters of e-chain®. For the cables inside of the energy chains, the company opted for chainflex® type CF211.038 resolver cables and type CF210.UL.15.15.02 servo cables. Pre-fitted TH3 energy chains and internal chainflex® cables were supplied ready for installation as readychain® energy chains.