Paper drying machine

• Main Author: Thorp, Benjamin A
• Format: Patent
• Language: English
• Published: 24.06.2003

Paper products, e.g., tissues, have conventionally been manufactured by forming a wet paper web on a fabric-carrying sheet, which then carries the paper web through a pressing section to remove the excess water from the web. After pressing the web to remove excess water, the paper web would then be fed to a separate drying section to fully remove the remaining moisture from the web. This step of pressing the web, however, reduces bulk and absorbency. Therefore, as opposed to leaving the web as a flat sheet on a single plane, rotatable air-heated drum dryers over which the web traveled were utilized in combination with an imprinting fabric sheet. Dryer hoods and air supply ducts are widely used in connection with these rotary drums, wherein pressurized drying air is introduced into the roll or at various points in the hood to contact one exposed surface of the wet web as it progresses around the dryer with the exit path for the air being positioned on the other side of the rotary drum. This process is known as through air drying (TAD). A paper drying apparatus to dry a paper web carried on a fabric sheet includes a first rotatable drum to carry a paper web. A second rotatable drum is positioned downstream of the first drum with respect to the paper web carried by the first and second rotatable drum. A third rotatable drum is positioned downstream of the second rotatable drum to carry the paper web. A first air supply directs air through the first rotatable drum in a first direction to dry a paper web carried on the first rotatable drum. A second air supply supplies air through the second rotatable drum in a second direction opposite to the first direction. A third air supply supplies air through the third rotatable drum in the first direction. The first direction is one of a direction from an inside of a respective drum toward an outside of the respective drum and from the outside of the respective drum toward the inside of the respective drum.