Smooth production runs In the past, cyclists were frequently tempted to counteract slack chains by vigorous pre-tensioning. Result - sluggishness, often accompanied by clicking noises, caused by too much stress on the chain links. Today's generation of cyclists knows nothing of their parents' tensioning problems. Their bikes already come with effective built-in tensioners. Chain/belt tensioners in materials handling installations share the same basic aim - to increase chain or belt life and thus, in turn, help components to continue to run smoothly. A Murtfeldt tensioning device can keep the non-driving free length's combined force of chain weight plus centrifugal force under control, one of our basic aims having been to find a way of matching the spring force to individual chain sizes and installation conditions. Similarly for belt tensioners: Different drive and conveyor belts need different rates of pre-tensioning.