Headbox
Also: headbox, slice
The component of a paper machine that deposits stock onto the forming wire at controlled consistency, flow, and width.
The headbox is the stock distribution chamber at the wet end of the paper machine. It takes stock from the approach flow system and lays it onto the wire through a narrow slot called the slice. Modern dilution-control headboxes adjust consistency across the machine width to control grammage profile.
Headbox design is a key driver of formation and cross-machine uniformity. Hydraulic headboxes predominate; air-cushioned headboxes are legacy equipment on older machines.
Related
- Fourdrinier. The traditional single-wire paper machine design where stock drains through a moving mesh. Invented 1803, still dominant for many grades.