Packaging with the latest vacuum technology

17 May 2021

Vinzenz Murr GmbH has recently updated its central vacuum system to make use of modern technology that offers a pressure-regulated and energy efficient solution for use in its packaging processes.

Vinzenz Murr GmbH has been producing meat and sausage products for around 120 years. Since 1970, the company has been producing its meat and sausage products in the Munich district of Obersendling. Products are sold almost exclusively through 270 shops across Bavaria.

Since 2004, Vinzenz Murr has been using a central vacuum system from Busch Vacuum Solutions to supply vacuum to all the packaging machines in its Obersendling butchery plant. This central vacuum supply consisted of a vacuum system with three R5 rotary vane vacuum pumps and a total of three vacuum boosters. The vacuum system was operated using a cascade control unit. This means that only as many vacuum pumps were in operation as were necessary for the current demand. This involved pumps being switched on or off as required. A vacuum chamber with a volume 2m3 served as a buffer so that the necessary vacuum level was immediately available in the respective packaging chambers when needed. So far, four large thermoforming machines have been supplied with vacuum.

Frequency-controlled solution

When moving the vacuum system to another room, Alexander Brandl, managing director at the company, decided to swap the rotary vane vacuum pumps equipped with standard motors for frequency-controlled rotary vane vacuum pumps to enable them to more precisely adjust the performance of the vacuum system to meet actual demand. This is because the packaging machines are used to package products ranging from several kilos in weight to small portion packs for self-service counters. This means that very different tools are used for packaging and therefore the volumes of the packaging chambers vary considerably. Due to relatively small quantities, the total volume of the packaging machines changes frequently and therefore so does the vacuum system's power requirement.

Brandl specified the latest generation of intelligent vacuum pumps – the R5 PLUS from Busch Vacuum Solutions – in part due to how easy the system was to handle via a touchscreen.

The new system has now been in operation since June 2020. Thanks to pressure control, each individual vacuum pump can precisely maintain the specified vacuum level and compensate for changing pumping speeds via the rotational speed. The individual integrated primary control units in each pump communicate with each other via a higher-level secondary control unit – the PLUS Master Control. In this way, the overall performance of the vacuum system is able to adapt precisely to the actual demand. The central vacuum system can be easily operated via the PLUS Master

Control touchscreen

After several months of operation, it became apparent in practice that the vacuum system's control unit is far more responsive than with the previous system, which also responded to changes in demand by simply switching individual vacuum pumps on and off, but in coarser steps. The converted vacuum system can now guarantee compliance with cycle times and a precisely defined vacuum level in each individual package.

The new rotary vane vacuum pumps are larger than the vacuum pumps previously used. This is because in the future, even more thermoforming machines will be connected to the central vacuum supply. But the proven old R5 rotary vane vacuum pumps that they replaced are not to be abandoned in the future. It is expected that one or more of them will be used in the future on tumblers as a single unit.