| 摘要 |
<p>A method is disclosed for controlling the level of the solvent vapor/overhead gas interface in a spin-cell. This method is used in a process for forming a nonwoven plexifilamentary web of synthetic crystalline polymer by extruding a solution of such polymer from one or more spin packs into a substantially closed spin-cell. The solvent vapor level (34) is controlled by means of a displacement body (32) which is suspended from a load cell (41). The displacement body (32) is partially immersed in the solvent vapor with the remainder being immersed in the overhead gas covering the solvent vapor. The displacement body's apparent weight is measured by the load cell (41) and used to control the rate of solvent vapor removal from the spin-cell (24) thereby maintaining the solvent vapor/overhead gas interface (34) in the spin-cell (24) at a desired level.</p> |
