Rieter

The importance of can format for automated can change

Index

It is customary in rotor spinning mills to use round cans, which are arranged in two rows, one behind the other, on the rotor spinning machines. Replacing a round can which has run empty in the back row entails considerable mechanical and control effort for a can changing system. The systems developed for such concepts have therefore not established themselves to date.

In the context of transport automation the rectangular can has been launched on the market and has enabled can change on the rotor spinning machine to be automated (Fig. 63). Rectangular cans enable the available space to be allocated clearly in terms of the spinning can and the spinning position (only one can stands under each position). This layout of spinning can and spinning position in relation to the gauge was one of the essential preconditions for simple, automated can change on the rotor spinning machine.

Another advantage of rectangular cans is that the surface under the rotor spinning machine can be utilized much more efficiently. The volume and thus the contents of the rectangular cans are thus up to 65% larger than round cans. This results in longer running times per can and fewer stoppages at the spinning positions for can changes.

The can filling and can changing mechanisms required for rectangular cans on the drawframes have been successfully used for some years. While limitations on delivery speeds had to be accepted with the first generation of these drawframes, delivery speeds of up to 1 000 m/min can now be achieved without any difficulty. At the delivery end of the  drawframe a can trolley (can buffer) contains empty cans ready for filling and also accepts filled cans. A shuttle pulls empty cans one at a time from the can trolley under the turntable. After the can has been filled, the shuttle pulls the full can into the empty position on the can trolley and removes the next empty can from it for filling.

Fig. 63 – Can formats in the rotor spinning mill. Rectangular cans for economical transport automation