Rieter

Vacuum and energy consumption

Index

A relatively high vacuum is necessary to ensure reliable extraction. It should be approx. 600 to 800 Pa for cotton and approx. 1 000 to 1 200 Pa for man-made fibers. It should be borne in mind here that there can be a considerable drop in pressure between the fan and the last spindle. The longer the machines (Fig. 68) and the larger the air flow rate, the greater the drop in pressure. The air flow rate is usually between 5 and 10 m3/h. The energy consumption required for fiber extraction is substantial. It can account for up to 1/3 of the machine‘s drive power and also depends on the length of the machine and the air flow rate. For example, energy consumption at 10  3/h is 4.5 times higher than at 6 m3/h, due to the considerably higher vacuum.

Fig. 68 – Pressure drop in the fiber extraction system, starting from the first spindle on the fan side; N -spindle No.; I: short machine; II: long machine