Dryer section
Also: dryer section, drying section, Yankee dryer
The part of the paper machine where the sheet dries to final moisture by contact with steam-heated cylinders.
The dryer section is a long line of steam-heated cast iron cylinders (typically 1.5 to 1.8 m diameter) that the sheet passes over in an S-pattern. Each cylinder contact evaporates a few grams per square metre of water. A modern paper machine has 50 or more dryer cylinders.
Tissue machines use a single giant Yankee dryer (4.5 to 6 m diameter) instead of a series of smaller cylinders, because the creping doctor blade at the end of the Yankee defines the sheet structure.
Related
- Press section. The part of the paper machine after forming where water is squeezed from the wet sheet by passing it through pressurized roll nips with felts.