Gentle, Yet Effective, Drying on the Fly
When the paper is pressed, a solid content of approximately 55% is reached. The remaining moisture is removed by vaporization. This is done by steam-heated cylinders in the drying section of the paper machine. The heat transfer to the paper is made by direct contact to the outside wall of the cylinder. For special paper types, a combination of contact and convection drying is used.
Pressure Measurement on Drying Cylinders with the VEGABAR 52
During the drying process, heat is extracted from the steam. A condensate film forms on the inside wall of the cylinder. This condensate impairs the heat efficiency of the transfer to the paper. It is kept as thin as possible by skimming it off continuously. By measuring the pressure difference between the inlet and outlet with the VEGABAR 52, the effect of the drying cylinder is continuously monitored. A water-filled U-tube reduces the steam temperature from 320°F (160°C) to below 248°F (120°C) for the VEGABAR 52. The highly overload resistant CERTEC® measuring cell ensures the necessary reliability even in case of pressure shocks in the transmission line.