In the single-cylinder dryer, web shrinkage is completely avoided. This is obtained by tensioning two bands along the web edges, on the outside of the drying felt.  Due to the absence of shrinkage, the mechanical properties of the web are well defined, including ultrasonic evaluation of fibre orientation distribution.

The single-cylinder dryer of the FEX paper machine.

In the 10-cylinder dryer, heat can be supplied from both sides of the sheet, or from one side only. The electric energy input is 12 kW per cylinder. The cylinder temperatures can be set between 20 and 110°C. Drier speed is within the range 5 – 45 m/min, depending on web grammage level.  Web dryness is measured at the dry end, and the drier speed can be controlled to give a preset final dryness.  Thereby different sample rolls can be graded with respect to “driability”.

The 10-cylinder dryer of the FEX paper machine.