Cables for the foodstuffs industry
The battle against bacteria
In the foodstuffs industry, the top priority is resistance against biological influences like microbes and fungi. In cheese factories, the bacteria that help the cheese ripen can corrode a conventional cable in a matter of months, leading to short circuits. Sheath materials made from special TPE, such as those used on Lapp’s ROBUST cables, repel bacteria and are easy to clean. The secret of Lapp’s special thermoplastic elastomer is the smooth surface. This is achieved with a smart mixture of additives that fill microscopic gaps in the material and that stay bonded in the plastic matrix even after heavy cleaning with a steam jet. The combination of strong substances with flexible polymer chains in between gives the mixture rubber-like properties, while being as easy to process as thermoplastics. Some suppliers offer PUR cables for use in the foodstuffs industry that offer extremely high mechanical strength. But PUR is hydrophilic, meaning that it attracts water. Special TPE, by contrast, is hydrophobic.
All of these mixtures, however, are powerless against larger lifeforms like rodents. That is why underground cables are protected with flavourings like vanillin or are specially reinforced. Alongside steel reinforcement, other materials are available that splinter when bitten and spoil the hungry animals’ appetite. When it comes to the devastation that martens can cause, certain materials that do not take on odours may provide a solution. Scientists believe that the reason why martens attack cables has to do with battles over territory. Martens mark their territory with their droppings, urine and sweat from glands in their paws. Their rivals try to destroy these markings. A cable that does not take on odours cannot be marked and is therefore not attacked.