Method of paper machine control and apparatus for the method
US6904331B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2002 |
| Grant date | Jun 7, 2005 |
| Priority date | — |
| Expiry date | Apr 2, 2023 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21G9/0036
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The present invention is characterized in that in a simulation for predicting a steam pressure setpoint after grade change, an initial moisture percentage is evaluated from differences between bone-dry basis weights and between machine speeds before and after grade change; the bone-dry coated weight of a size is evaluated from the flow rate and concentration thereof; and then the dryer inlet moisture percentage of a web after a size press is calculated from the coated weight. Thus, the invention intends to improve the quality of products through precise dryer control, as well as reduce the time required for grade change, by precisely predicting the web's initial moisture percentage at the dryer inlet after grade change and precisely and quickly controlling dryer steam pressure during grade change.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.