| 摘要 |
<p>The invention concerns a method for measurement of the permeability to air of a drying wire, in which method the measurement is carried out continuously while the drying wire (F) moves. In the method, the drying wire (F) is guided to run so that it by-passes a blow box (10) and a measurement box (15) free of contact. In the method, the pressure in the measurement box (15) and/or the relative change in said pressure is/are measured when the blow box (10) is connected to blowing. The pressure and/or the relative change in the pressure is/are compared with earlier measurement results and/or starting values. The permeability to air of the drying wire (F) is determined on the basis of comparison of the pressure and/or of the relative change in the pressure, and the contact-free measurement is produced by guiding the flow into or out of the measurement box (15) to pass through the gap between the measurement box (15) and the drying wire (F). Further, the invention also concerns a device for carrying out the method for measurement of the permeability to air of a drying wire, which device is placed in the vicinity of the moving drying wire (F). The device comprises a blow box (10) and a measurement box (15), the drying wire (F) being fitted to by-pass said boxes free of contact so that the flow into or out of the measurement box (15) is guided to pass through the gap between the measurement box (15) and the drying wire (F), as well as a pressure gauge for measurement of the pressure in the measurement box (15) and/or of the relative change in the pressure. <IMAGE></p> |
