Method and regulation arrangement for controlling dewatering profile of a former
US6855230B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 2001 |
| Grant date | Feb 15, 2005 |
| Priority date | — |
| Expiry date | Jun 8, 2021 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21F9/003
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
In a paper or board machine, the cross-direction profile of a 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 measurement can be by passing an alternating current of low frequency to a current rail situated in the second dewatering element (64, 65) and by measuring the strength 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.