1. Field of the Invention
The invention relates to a method for automatically loading a feed line with bulk material, in particular a plastic granular material, in a suction delivery system having at least one material separator, which is provided at a distance to a reservoir. Furthermore, the invention relates to a device for implementation of said method.
2. Background Description
Pneumatic delivery systems are operated generally in such a way that the setting of the material to air mixture is fixed at the material feeding point. Among experts, this is the load of the feed line. Basically, different designs of material feeding points are known, whereby the problem arises for all of them that an optimal mixture cannot be achieved for varying delivery lengths as a result of the fixed setting.
Pneumatic delivery systems for bulk material are planned and designed in such a way that flexibility is achieved for material distribution. Different delivery targets are served in sequence from a single material source, such as, for example, the reservoir. Based on the set values fixed at the material feeding point, a load results for the delivery in accordance with the fan characteristic and the length up to the material separator. For practical reasons, this is set in such a way that delivery is ensured for common material types and the longest delivery distance. However, the load is smaller if shorter delivery distances are served. Reduced load increases the wear of the feed lines and the receiving devices, for example the material separators, at the delivery target due to higher bulk speeds.
By reducing the load, the flow of the bulk material is reduced at the same time, although the bulk material is transported faster through the pipeline. Wearing of the material itself is also given, which creates deposits in the feed line or becomes effective as dust.
An apparatus for conveying bulk material, in which a variable amount of a conveying gas may be introduced to the bulk material to be conveyed by a vacuum conveying system, is thus known from DE 100 39 564 A1. However, practical tests have shown that the control of the conveying gas alone does not result in a prevention of the disadvantages mentioned above.