with a condensing element the condensing device and the suction element are configured to allow for the removal of air from the condensing element the suction element has a housing and an insert the insert is displaceable with respect to the housing along a guide the insert is arrestable with respect to the housing application_number US 93056101 A description reference will now be made in detail to embodiments of the invention examples of which are shown in the drawings each example is provided by way of explanation of the invention and not meant as a limitation of the invention for example features illustrated or described as part of one embodiment may be used on another embodiment to yield still a third embodiment these and other modifications and variations are within the scope and spirit of the present invention the material feed 7 according to fig1 consists in a convention spinning machine either of a can or a roving bobbin a sliver 71 shown with a broken line is supplied from the can to the drafting arrangement 1 in the case of a roving bobbin the roving is drawn off from the circumference of the bobbin the fibre structure namely the roving or sliver reaches the zone of the drafting arrangement 1 via a deflection apparatus the drafting arrangement comprises several pairs of delivery rollers 11 preferably equipped in part with aprons the sliver 71 is drafted weakly between the first and second pair.