The importance of intralogistics is increasing worldwide. System providers such as viastore systems plan and implement automated storage systems – ranging from small parts and pallet warehouses to shuttle warehouses – including storage and retrieval units (SRUs). These must work quickly and flexibly in order to be able to react to changing order cycles and quantities. Users also demand fail-safe systems to avoid unplanned downtime. viastore relies on the flexible chainflex cables from igus to supply its storage and retrieval units with energy and data.
Within intralogistics, providers organise internal material flows by means of technical systems and software solutions. An elementary component here are automatic storage and retrieval units (SRUs), which move goods and store them in and retrieve them from the compartments of the high-bay racking.
Since 1970, the Stuttgart-based company viastore has been developing and producing storage and retrieval units for all types of warehouses, in all size and speed classes, and differentiates between three basic types according to travel speed and payload. The smallest system, "viaspeed", has been specially designed for plastic containers and cartons and for a payload of up to 50 kg. With a travel speed of 6 m/s and an acceleration of 3 m/s², it is highly dynamic. The SRU "viaspeed XL", on the other hand, picks up loads of up to 300 kilograms and transports containers and trays. It has a travel speed of up to 5 m/s and accelerates vertically at 2 m/s2. The system can still be used at temperatures from minus 40 degrees Celsius to plus 45 degrees Celsius. Finally, the most powerful storage and retrieval unit, viapal, handles pallets, wire mesh boxes and other loads of up to three tons. The dynamic travel drive makes a travel speed of 3 m/s and a vertical acceleration of 1.5 m/s2possible.
These performances show that in all SRUs, whether small or large, the demands on the systems are very high. viastore offers solutions that are highly dynamic and flexible, allowing for increased number of retrieval and storage actions when the number of items and orders increases. Warehouse operators expect automated solutions to adapt to ordering processes and to respond faster to peak times. They also demand reliable and durable solutions that ensure high plant availability and keep maintenance costs low. Against this backdrop, it is crucial that all components in the units, such as the energy supply solution, also function superbly under precisely this high requirement profile and need to be maintained only rarely, if at all.
Today, these requirements are met by the maintenance-free polymer energy chains and chainflex cables from igus. They are installed in the lifting gear on the mast of the storage and retrieval units and supply the systems with energy and data like an umbilical cord. Especially the fast lifting movements and vibrations at large unit heights or at high travel speeds place an extremely high load on the cables. Conventional cables can often form corkscrews, which can lead to core breakage.
This is why igus began developing special cables under the brand name chainflex for dynamic use in energy chains back in 1989. A special feature is their specific structure consisting of cores wound in bundles. Here, the cores are not wound in layers around the centre of the cable, but are wound together in three, four or five cores, which are then wound together again to form a complete stranding of the bundles. Additionally, gusset-filling extruded inner jackets fill the spaces between the cores. The effect: The stranding cannot unravel and each core is moved equally in the inner and outer radius when moving in the energy chain. One-sided stretching and compression, which often lead to core ruptures or corkscrews, are a thing of the past.
But temperature-resistant cables are also important to viastore for use in deep-freeze warehouses. They have to cope with small bend radii and millions of strokes at very low temperatures. Not only the design principle but also the used materials qualify the cables for continuous use in this application. For example, in particularly cold ambient conditions, cables with specially developed highly cold-flexible TPE outer jacket materials are used.
But the variety of cable types in the igus range was also important to the customer. viastore can flexibly offer 1,244 chainflex cables – from control and servo cables up to motor and robot cables as well as bus, encoder and fibre-optic cables .
igus gives a three-year guarantee on the chainflex cables. The company can offer this security because it tests all cables under real conditions. The test results flow into a database, on the basis of which the expected service life of the products is calculated, which every user can compute on their own in a time-saving way on the igus homepage. The basis for the service life calculator is the igus database, which has grown over decades and in which the results of thousands of tests from the test laboratory and decades of experience in the development and production of chainflex cables are stored. On this basis, the online tool calculates the expected service life of the chainflex cable. Otto Funk, Head of Design at viastore SYSTEMS, emphasises why this is so important: "We need to know what the expected service life of the chainflex cables is in order to be able to reliably plan the replacement cycles. Unplanned system downtimes must not occur under any circumstances. Therefore, we would like to be able to make statements to our customers about the durability of all components that are installed in our SRUs," says Friedbert Dannenhauer, Deputy Design Manager at viastore SYSTEMS. igus has developed a variety of other online tools to make it easier for the system integrator to select the right products, configure them and order them. Such additional services help to save time and reduce costs. The people in charge at viastore also appreciate this. Friedbert Dannenhauer and Otto Funk are not only satisfied with the chainflex cables from igus, but also with the service. "The advice from igus and the cooperation over the entire course of the project is really very good. The idea of partnership is always in the foreground," concludes Friedbert Dannenhauer.