kubler articles

Contact oil-free sliding contact minimises maintenance work

Kubler 2/9/2014

Contact Oil-Free Sliding ContactPackaging is subject to high requirements, especially for food products - it ensures hygienic and nutritious food for long periods and it provides in the same time the customer with information about product characteristics. In this context, slip contribute significantly for example to the safe manufacturing of vacuum packages, in which the product is placed in a bag made of a plastic or aluminium film and from which the air is then removed. The contact materials of the slip rings of the SR060E type ensure low-wear operation without contact oil.

We do not notice good food packagings. They often only reach our awareness if they do not meet our expectations - for example, when they are hard to open or damaged. Nevertheless, packaging food is not an easy task, as it must be made sure that it can in no way be contaminated.

Pursuant to the stringent standards and hygiene rules of the German Regulation on the Hygiene of Foodstuffs, in short LMHV, all critical operations on the way to the consumer must be continuously monitored, documented and ensured and guaranteed by means of appropriate procedures. These rules do not only apply to the finished product, but to the whole manufacturing process, including the packaging machines, their components and all of the materials used during the production.

Kubler offers slip rings developed especially for the use in this highly regulated sector, which can be used in packaging machines for the food processing branch. In packaging devices, slip rings are in charge of the rotary transmission of energy, signals and data between stationary and rotating platforms. In addition to resist reliably to the conditions of their operating environment, they also ensure trouble-free operation and a long service life.

For the slip rings SR060E and SRI085, this is true both for the material of the drive unit and for all interface components such as connections and seals. The SR060E is designed for up to 3 load and 2 signal transmissions and suits many different applications: from heating and monitoring of the sealing rollers in flowpack machines up to stretch film wrapping machines.

Efficient cleaning must be ensured

Microbiologically perfect products are a vital aspect for every food manufacturer. The Kubler slip rings have all features to meet the hygiene and cleaning safety requirements in aggressive environments. Thanks to their smooth and straight surfaces - without any undercut - they are easy to clean. Their oval, round housing is fully encapsulated, safely protecting the machine against abrasion dust, since the protection of the processed food requires that no machine element shall produce any substance that might be harmful to health or have a negative influence on the taste or smell during the production process.

For easy and safe cleaning, the materials of the machine elements must also resist aggressive detergents and disinfectants, and any reaction of materials must be excluded. They must be corrosion-resistant, mechanically robust and their surface must be completely insensitive.

Low-maintenance up to maintenance-free

A trend in mechanical engineering is the increasing maintenance optimisation with the goal of building plants requiring particularly little maintenance or even no maintenance at all. With the slip ring SR060E, Kubler wants to show that this is possible also for slip rings: The slip ring equipped with silver, bronze and precious metal contacts (contact oilfree) requires maintenance only all 100 million revolutions. This maintenance is then minimal, consisting simply in vacuum-cleaning the dust.

Even in the case of continuous operation, which is generally the case today with this kind of machines, this value is practically negligible. Moreover, the SRI085 uses non-contact signal transmission to the moving machines, operating in this area totally without mechanical wear. Today packaging machines, in addition to logistical optimisation and continuous operation, also experiment constant increases in production performance and in products speed on the conveyors. This fast pace results, for example for heat-sealing of blister packagings, in increasingly short contact times for the films. This is made possible thanks to the high rotary speeds of 500 and even 800 RPM permitted by these slip rings.

The load current dimensioning of up to 20 resp. 25 amperes allows very short heating times and thus an optimal temperature regulation - even for shortest contact times. The protection level IP64 furthermore allows any kind of cleaning process, from the "damp cloth" up to the water jet. Flat plugs, fastening screws and anodised aluminium parts minimise the installation time.

Packaging represents an increasingly important media for foodstuff manufacturers: Film packaging provides the consumer with information about product features, nutritional content and ingredients, and it guarantees hygienic and nutritious food for long periods of time. Kubler slip rings contribute significantly to the safe manufacture of vacuum packages, in which the product is placed in a bag made of a plastic or aluminium film and from which the air is then removed. Because only the high-quality packaging around the food preserves the composition of the gas inside so that we can enjoy still fresh and safe food.