The “JunkRagger” braid winch from Hellenbrand removes the spinning contaminants, such as wires, tapes, films and insoluble raw material residues, from the pulper. The impurities form a braid, which is transported out of the pulper by means of a braid wheel and a pressure roller. The braid plant is an important part of the dissolution process in stock preparation. Disturbances in pigtail operation can lead to production downtime. The reason for accidents in the process lies in flows and forces in the pulper that are difficult to estimate.