GB477684A - Improvements in or relating to drying apparatus - Google Patents

Abstract

477,684. Drying webs. OFFEN, B. April 1, 1936, No. 9663. [Class 34 (i)] A method of drying sheet or web material consists in introducing the material within a hooded enclosure, circulating drying air along the surface of the material, discharging against the material air at high pressure and high velocity, and withdrawing the drying air and the high pressure air from within the enclosure. In the construction shown, the web or sheet 8 to be dried is carried over rollers 7 across the mouth of a hood 9. The hood has a pipe 10 divided by a partition 13 into an air supply chamber 11 and an air exhaust chamber 12. Air supplied to the chamber 11 through duct 26 passes through an opening 14 into a chamber 15 from which it escapes through louvres 16 into contact with the web 8. The air is withdrawn through louvres 17a, 17b, passing into the chamber 12 through openings 19a, 19b. Spaced baffles 20 of electrically nonconductive material extend throughout the height of the hood close to the web 8, forming separate passages 21. Transverse bars may be provided between the baffles 20 to break up the flow of air. The pipe 10 is rotatably mounted so that the hood may be displaced from the web 8. The web is treated by compressed air which is passed through a dehydrator 41 and an air cleaner 42. Some of the air passes through a heater 43 to a manifold 49 from which it is directed through jets 50 against the web. The drying air and high pressure air are withdrawn through discharge duct 25. More air is withdrawn than is supplied to the hood by duct 26 and manifold 49 whereby outward leakage of air from the hood 9 is prevented. The web after being dried is chilled by compressed air passed through a cooler 44 and discharged through jets 56 in a manifold 55.