Couplings for packaging equipment
Reliable, powerful, flexible, and safe: Today, modern packaging machines have to meet many demands. If these are used in the food industry, cleanliness and hygiene also play a very important role. The drive elements used there also often have to meet special requirements. The Klingenberg coupling manufacturer R+W offers suitable coupling solutions for this.
Couplings make an important contribution to reliable drive technology at many points in packaging plants. Depending on the application, however, these often have to exhibit further properties in addition to the general requirements such as torque transmission, compensation of misalignments or safe torque limitation as overload protection. If these are used in packaging machines for food, hygiene, food safety or corrosion resistance, for example, often play an important role. However, depending on the application, the requirements can differ significantly.
Couplings along the process chain
If we look, for example, at the process chain for manufacturing and filling carton beverage packaging, the special features required here can be easily identified. As with most other components installed within such packaging machines, the same applies to couplings: They often have to be resistant to and protected against aggressive cleaning agents as well as liquid media, some of which are acidic.
Along such a packaging and filling line, a wide variety of R+W couplings are installed at numerous points for the most diverse work steps. These include, for example, safety couplings for the cutting tool of the carton that forms the basis for the packaging, or couplings for the filling machine that fills milk, juice or similar. When cutting the cardboard, an overload can occur at any time due to jammed cutting tools. In this case, mechanical safety couplings from R+W separate the motor and tool sides from each other within a few milliseconds, so that neither the knife nor the motor are damaged. Couplers also ensure reliable operations and efficient processes when folding into the typical beverage bag shape.
Along the process chain, there are further steps in which coupling solutions play an important role. For example, when attaching the cap or the straw, where the machine attaches two small adhesive dots to the milk carton and, in a second step, sticks the straw on
Once the beverage packaging has been produced and filled, the manufacturer sends it on its way. For this purpose, several packages are assembled, packed in batches and shipped on pallets. During these operations, couplings also reliably transmit or limit the torque and protect against overloads or related damage to the equipment. If you think even further ahead in the product life cycle of a package, it becomes clear that a wide variety of couplings accompany it comprehensively – even after the package is disposed of in the trash. This is because couplings also play a decisive role in various work steps in recycling technology.
Product portfolio with many variants
In order to meet the respective requirements of the different work steps, R+W has numerous coupling series that can be obtained in a wide variety of versions. In many areas of food processing or packaging, for example, the material used plays a decisive role. R+W therefore offers the complete range of relevant coupling types in stainless steel, which meet many of the requirements there – such as with regard to corrosion resistance or a safe and hygienic cleaning option. In applications where stainless steel material is not required, the coupling components can also be surface finished, such as anodized or oxidized. Other surface treatments are also available on request. Depending on the requirements, there are different types of couplings that provide the necessary properties.
Sealed safety couplings
Due to strict hygiene regulations, many applications in which safety couplings are used require a coupling solution in which no substances can escape or enter. The safety coupling must be designed in such a way that no substances, such as lubricants, can get to the food.
The option of completely sealing the R+W torque limiting couplings prevents grease from escaping and at the same time prevents the ingress of substances harmful to the clutch. With this solution, all sealing elements are integrated in one component. An O-ring is inserted into the basic body of the coupling and covered by an extended shifting ring. An important advantage of this design is that the outer dimensions of the coupling and thus the required installation space remain small – unlike solutions in which a complex housing is used to seal the coupling.
Torque transmission as required
If torsionally stiff transmission of torque from the input to the output side is required, metal bellows couplings are often used. If, in addition, safe use at very high temperatures, humidity and in the environment of aggressive media must be guaranteed – which is regularly required in the food processing industry – R+W can offer a suitable coupling even from the standard range with its BKS model. This is made entirely of stainless steel and is designed with easy-to-fit clamping hubs and a welded bellows-hub connection. Due to the metal bellows as a compensating element, the coupling can also compensate for axial, lateral and angular shaft misalignments. But all other models of R+W metal bellows couplings, from 0.1 to 100,000 Nm, are also available in the corresponding design. Special solutions enable the transmission of even higher torques.
In some applications, where vibrations and shocks occur, damping properties are required. The elastomer couplings of the EK series are suitable for these applications. Thanks to a connecting element made of TPU, the so-called elastomeric ring, the coupling enables precisely this property. Depending on the requirements, different shore hardnesses, i.e. degrees of hardness, can be selected. Depending on the design, the couplings are available with (split) clamping hub, conical clamping ring or keyway connection, among others, and can be obtained for torques up to 25,000 Nm.
Couplings play an important role in packaging technology. The examples show how many different influencing factors have to be taken into account. In addition to the absolute accuracy of fit, high-performance materials and high-quality workmanship are crucial. In close dialog with the design engineers of the user companies, R+W continuously develops its couplings in order to be able to offer solutions tailored to the respective requirements.