Closed-loop monitoring and identification of CD alignment for papermaking processes
US8224476B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2010 |
| Grant date | Jul 17, 2012 |
| Priority date | — |
| Expiry date | Apr 2, 2031 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21G9/0054
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Alignment is a critical component for modeling a cross-directional (CD) papermaking process. It specifies the spatial relationship between individual CD actuators to paper quality measurements. Misalignment can occur unexpectedly due to sheet wander or CD shrinkage variation. In certain applications and circumstances, a misalignment of one third (⅓) actuator zone width can result in significant paper quality degradation. Detecting a misalignment and identifying CD alignment in closed loop are highly demanded in paper mills but these are nontrivial problems. A technique for maintaining proper CD alignment in sheetmaking systems entails monitoring the alignment online, triggering closed loop identification if misalignment is detected, and then deploying the new alignment. No personnel intervention is required.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.