| 摘要 |
<p>A method and a regulation arrangement for controlling the dewatering profile in a former of a paper or board machine, which former comprises two forming wire loops (50, 60) having dewatering elements (52, 53, 64, 65) placed inside them, of which elements at least one comprises a blade element (64, 65) which extends transversely across the web with respect to the running direction of the wires and is in contact with one of the forming wires. In the method, the cross-direction profile of the flow channel defined between a first dewatering element (52, 53) situated inside a first forming wire loop (50) and a second dewatering element (64, 65) situated inside a second forming wire loop (60) is measured, and the location and/or the position of the blade element (64, 65) is adjusted based on the measurement result in order to regulate the thickness profile of a stock flow. The cross-direction profile of the flow channel can be measured by passing an alternating current of low frequency to a current rail situated in the second dewatering element (64, 65) and by measuring the strengh of the magnetic field created by it by at least two measuring devices which have been placed either in the first dewatering element (53) or, when the first dewatering element is a forming roll (52), in the same dewatering element (64) as the current rail.</p> |
