Stäubli robots in packaging line for hard cheese blocks

Stäubli robots in packaging line for hard cheese blocks

Hygienically automated – flexible and space-saving

In hard cheese production at BMI (Bayerische Molkereiindustrie) in Jessen/Saxony-Anhalt, Germany, two cells, each equipped with a hygienic Stäubli six-axis robot, take over the primary packaging of freshly produced 15- and 20-kg cheese blocks at 10-second intervals for around 20 hours. This is followed by complete washing to the highest hygiene standards. This exceptional concept offers benefits in terms of performance, space requirements, hygiene and flexibility.

To produce 35,000 tons of hard cheese per year, about 350 million liters of milk are needed. Since each dairy cow yields around 10,000 liters of milk a year, around 35,000 cows – most from Saxony-Anhalt, Saxony and Brandenburg – supply the necessary raw material for the hard cheese factory of the BMI dairy cooperative in Jessen. The overall site, with mozzarella cheese factories, processes some 1.5 million liters a day.

Flexible large-scale production on state-of-the-art equipment

This site, which also produces whey powder products, is not only the largest cheese factory in the BMI group, but also a major producer throughout Germany, especially since its product diversity is broad and its production is highly flexible: BMI produces Cagliata, white and red cheddar, Edam and Emmental among others in Jessen. A large portion of these products go to industrial customers, but they also go to retail chains for end consumers under the Paladin brand or private labels.

Between 2017 to 2019, the company invested the impressive sum of more than €100 million, including investment in a new hard cheese factory to produce these volumes and varieties economically with consistently high quality. The entire plant runs 20/7, as Thomas Benicke, production manager at the hard cheese factory explains, “We produce for 20 hours. Then the entire plant stops, gets cleaned, and a new production cycle begins.”

Primary packaging of cheese blocks in two robotic cells

This pace also applies to the final stage, namely packaging. When the cheese leaves the drainage belt, it enters one of six Tetra Pak Casomatic SC7 systems via a pipeline. These systems continuously and fully automatically handle pre-pressing, forming cheese blocks, and filling. The final product is cheese blocks weighing precisely 15 or 20 kg, ready for packaging.

BMI commissioned Lemmermeyer GmbH & Co KG Edelstahl-Anlagenbau in Deiningen, Germany, which has extensive experience with handling and packaging lines for the food industry – and has broken new ground in this area.

5.5 tons of cheese per hour packed in blocks

Three of each of the six Tetra Pak columns are assigned to a robotic cell with a Stäubli six-axis TX-200L robot in HE (humid environment) design. With a load capacity of 100 kg and reach of 2.60 meters, the robots are optimally prepared to handle the cheese blocks, and thanks to the gripper developed by Lemmermeyer, also have multitasking capability.

The base-mounted robot first grips a film tube and pulls it over the film shoe of the filling column. The system then pushes the 15- or 20-kg block of cheese into the tube, or two blocks of cheese if 40-kg units are being produced. The robot places the prepackaged cheese on a two-track pre-buffer conveyor belt, forming batches of 4 x 15 kg or 4 x 20 kg, or 2 x 40 kg. The batches are aligned and prepared for vacuuming and sealing. The following steps then take place: metal detection, labeling and leakage testing before the blocks are conveyed to the ripening area.

Because the robot is so versatile, the gripper developed by Lemmermeyer has several functions. A film spreader takes over the bag provided. Once the cheese has been pushed in, a flat gripper is used to place the block on the two-track conveyor belt. In doing so, it rotates every second block by 180 degrees so that the feed for the vacuum system is optimally utilized.

Flexible automation

The two robots perform their tasks with great endurance and a remarkable packing capacity of up to 5.5 tons per hour – equivalent to eight to 12 blocks per minute. Despite the high throughput, the systems are also extremely flexible. For example, the division into two identical cells ensures that production and packaging can still be performed even if one of the two cells is at a standstill.

If required, the blocks can also be moved out of the cell in the opposite direction and removed via the infeed conveyor belt. And of course, blocks with different weights can also be packed and handled. The control system, with clear visualization of the entire system, offers many possibilities.

Robots: Set for hygiene from base to wrist

However, the main reason BMI invested in flexible automation was not for personnel reduction but for high hygiene standards. Thomas Benicke: “As a cheese factory whose core production processes are prompted by bacteria, we must avoid the risk of introducing contamination at all costs. This is best achieved when humans do not intervene.”

That said, people do come into contact with the robots once a day during thorough lathering in cleaning mode. After just one process like this, a “normal” robot would hardly be operational. But Stäubli HE robots are prepared for this from base to wrist. All cables are routed inside the housing, which is also slightly pressurized to prevent liquid or moisture from penetrating. There are no dead spaces where residual dirt can settle, and the coating is also hygiene-compliant.

100 tons of block cheese a day – with a cycle time of 10 seconds

This means that the robots can be used reliably in processes where hygiene is critical – even with thorough daily cleaning e.g., by washing with water-based media with a pH range from 2 to 12. Regardless, they work durably over long periods despite the high strain; after all, as the “sole workers” in their cell, they handle around 100 tons of block cheese a day with a cycle time of 10 seconds. This is proven by the packaging line developed by Lemmermeyer at BMI in Jessen – as well as many other installations with hygienic Stäubli robots in the food industry.

Text by: Industrie Kommunikation Högel

In the six Casomatic systems and the upstream finishers, BMI produces around 35,000 tons of hard cheese a year at the Jessen site.

In two identical cells, the cheese blocks from three finishers each are packed into film tubes.

The hygienic Stäubli robots pack up to 5.5 tons of cheese per hour.

The workflow in the cell begins with the cheese block being pushed out of the column into the spread film tube.

The robots place the pre-packaged cheeses on a two-track conveyor belt, aligning the blocks and forming batches in the process.

The special grippers “multitask” and the entire packaging station is highly flexible.

For more information, please contact:

Sonja Koban

Marketing Manager & Division Business MarCom Manager

STÄUBLI TEC-SYSTEMS GMBH ROBOTICS

95448 Bayreuth / DE

Phone: +49 (0)921 883 3212

Fax: +49 (0)921 883 3444

Email: s.koban@staubli.com

About Stäubli

Stäubli is a global provider of mechatronics solutions with four dedicated activities: Electrical Connectors, Fluid Connectors, Robotics and Textile. We are an international group operating in 28 countries and represented in 50 countries on 4 continents. Our global workforce of over 6.000 employees is committed to maintaining a collaborative relationship with customers in nearly every industry to provide comprehensive solutions and long-term support. Originally founded in 1892 as a small workshop in Horgen/Zurich, CH, Stäubli is today an international group with headquarters in Pfäffikon, Switzerland.

https://www.staubli.com/de/en/corp.html

About Stäubli Robotics

Stäubli Robotics is a leading global player in robotics, consistently delivering engineering as effective and reliable as our service and support. A complete solutions provider for digitally networked production, Stäubli offers a broad range of 4- and 6-axis robots including robotic arms designed specifically for sensitive environments, autonomous mobile robots, driver-less transport systems (AGVs) and cobots for human-robot collaboration.

Robotic automation for industrial applications | Stäubli (staubli.com)

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