| 摘要 |
Virgin stock is conducted to a paper or board machine and further to a centrifugal cleaner installation ( 12 ) into its first centrifugal cleaner step ( 12 a<SUB>1</SUB>). From the first centrifugal cleaner step ( 12 a<SUB>1</SUB>) the accept is conducted into a multi-layer headbox ( 10 ) to form a layer of the web determined according to the concerned fraction. From a second step ( 12 a<SUB>2</SUB>) and/or from lower steps ( 12 a<SUB>3</SUB> , 12 a<SUB>4 </SUB>. . . ) of the centrifugal cleaner installation ( 12 ) a second fraction or more fractions are conducted into the multi-layer headbox ( 10 ) to form a second layer or other layers of the web, which are determined according to the pulp fractionation taking place in the concerned second step or lower steps. |
