In modern transport technology, the transportation in pipes seems to gain increasing interest despite some disadvan- tages which are inherent to the fluid mechanical principle This fact is proven on the one hand by the fast increasing number of small and medium pneumatic and hydraulic conveying plants (in-plant or interdepartmental) and on the other hand also by the increasing number of long cross-country pipe lines. Apparently, the advantages which are inherent to conveying piants using fluid mechanics are quite often outbalancing as a whole which results in economical conveying or production systems of which they are part of.
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