摘要 |
<p>The invention relates to a spin pump for conveying a liquid polymer melt. To drive the conveying means enclosed in the pump housing, a drive shaft is provided, which extends through the pump housing in a bearing bore, and which comprises an external end for connecting to a drive. To seal the outward extending drive shaft, a cooling sleeve is employed which connects in a pressure tight fashion to the pump housing. The cooling sleeve surrounds the drive shaft with a narrow gap therebetween, and the outer surface of the cooling sleeve is cooled by a coolant for increasing the viscosity of the polymer melt which enters the gap between the drive shaft and the cooling sleeve. With an increased viscosity, the melt acts to seal the gap without interfering with the rotation of the drive shaft.</p> |