| 摘要 |
The device has a cylindrical pipe-like shielding (1), which is divided into two half-shieldings (4) with diameters which are approximately concentric with each other. The half-shieldings are positioned to overlap on each other, by rotating and sliding in an open position or on an open part. The half-shieldings at an outer edge (5) are protected from many base parts with semi-ring sectors (6). The sectors are placed at the middle of concentric rings (7) which are provided with friction-arm lubricant. The lubricant is arranged at a central structure of extrusion heads. |
