Equipment Description:Fabrics For Cylinder Drying
Click here to print the FactSheet on A4 paper
The main function of a dryer fabric is to hold the paper web against the heated dryer cylinders within the drying section of the paper machine. Most dryer fabrics are of woven design constructed from various synthetic polymers, commonly polyester and polyamide, but can also incorporate PTFE and heat resistant polymers for specific applications. The main requirements of a dryer fabric are: Dimensional stability under tension; resistance to wear and / or damage; permeability retention; a uniform, smooth, surface to prevent marking and hold the paper sheet effectively and ease of installation. |
Warp The machine direction yarns in a woven dryer section fabric. Weft The cross machine direction yarns in a woven dryer section fabric Seam The means of joining the two ends of the fabric together. Spiral A continuous loop of yarn that is used to make the seam, or even an entire fabric. |
 Images courtesy of Voith Paper Fabrics |
Dryer fabrics must be able to resist degradation from humidity, temperature, wear (abrasion) and chemical cleaning additives. Modifications to the fabric design and polymer used to make the yarns can assist with this. For example, changing the weave pattern so that temperature resistant yarns are only present on the paper side of the fabric will prevent temperature related degradation at the sheet edges, where the paper web is not available to protect the fabric from the hot dryer cylinder (figure 3). The pressure of the steam used to heat the drying cylinders dictates the temperature to which the fabric is exposed. Above a certain limit, polyester yarn is no longer a suitable material for manufacture of fabrics and hydrolysis resistant yarns such as PCTA or PPS must be used instead. A fabric's permeability determines how quickly evaporated moisture can be removed from the pockets of the dryer section. Dryer fabrics can be woven to give very different permeabilities, depending on the machine requirements. Spiral dryer fabrics can be supplied to provide air permeabilities up to 16000 m³/m²/hr. |
Fabrics For Cylinder Drying was also mentioned in the following Fact Sheets (31):
|
These 3 companies are suppliers of relevant
equipment/services.
There are 5 other potential suppliers of relevant equipment/services. (This information is from suppliers listed in the Industry Directory Contact PITA to have your company listed here)
|