Method and apparatus for wrapping a plastic film around a load

摘要

The problem involved in wrapping a stretched plastic film around a load by rotating the load and the plastic film feed roll is often that the film will not adapt well enough to the shape of the load, will not form an elastically tensioned package, and will not necessarily be by its stretch ratio and thickness sufficiently uniform and suitable for the product in question. In the present invention, a method has been developed for wrapping a stretched plastic film around the circumference of a load by rotating the load and the plastic film feed roll each about its axis in order to unwind the stretchable plastic film from the feed roll and to wrap the stretched plastic film around the circumference of the load and by braking the plastic film in order to stretch it between the braking point and the wrapping point. The advantages of the invention are based on the fact the braking power which induces the stretching of the plastic film is regulated on the basis of the circumferential speed of the load. In this manner it is possible to achieve completely simultaneous stretching and wrapping, wherein the contact point between the load and the plastic film constitutes the downstream end of the film-stretching distance.