Method and installation for adjusting by-pass circulation in a head box in a paper machine/cardboard machine

摘要

The invention relates to a method for adjusting the by- pass circulation in a head box in a paper machine/ cardboard machine. In the method fresh pulp is conveyed along a pulp line L3, L4 to the head box 10. A pulp flow Fout is conveyed along a by-pass line L5 from the head box 10 to a pressure compensation vessel 40 and on through the pressure compensation vessel 40 back to the pulp line L3. The pulp flow is conveyed to a strainer 42, in which the inlet pressure P1 is less than the outlet pressure P2, and on to the line L4, which leads to the head box 10. The invention also relates to an installation for controlling by-pass circulation Fout in a head box in a paper machine/cardboard machine. <IMAGE>