Mini-Encyclopedia of Papermaking Wet-End Chemistry
Part Two: Definitions and Concepts

Jet-to-Wire Speed Difference

Papermakers adjust the jet-to-wire speed difference to fine-tune the paper structure. The "jet" is the narrow stream of papermaking furnish that comes out of the slice opening from the headbox. The "wire" is the continuous belt of forming fabric. Often it is possible to improve the uniformity of paper by running at a non-zero jet-to-wire speed difference. "Rushing the sheet" means that the jet speed is higher than the wire speed. "Dragging the sheet" means that the wire speed is higher than the jet speed. Especially in the case of dragging, increasing values of jet-to-wire speed difference tend to align fibers in the machine direction.

Request from the webmaster: Our goals include brevity and accuracy. Hopefully we have succeeded with the first goal without sacrificing the second. Please let us know right away if you find an error or omition. Also, please indicate points that need a clearer description.


RETURN TO INDEX PAGE OF ENCYCLOPEDIA

Home page Research opportunities Business opportunities Background information Links to wet-end chemistry E-Mail
This page is maintained by Martin hubbe, Associate Professor of Wood and Paper Science, NC State University, m_hubbe@ncsu.edu .