Procedure for boosting the ventilation in the hood of a paper machine

Abstract

A procedure for boosting the ventilation in drying sections of paper machines provided with a closed hood (1). In the procedure, air is blown on such surfaces which are susceptible to condensate precipitation. Air jets (F.sub.1,F.sub.2) are blown mainly obliquely downward through air ducts (11A,11B) disposed adjacent to both side walls (7A,7B) of the hood (1), above all towards the inner surfaces of the door, hatch and/or window structures (12A,12B,16,17) in association with the lower part of the walls (7A,7B) of the hood (1). The blowing air is taken to the air ducts (11A,11B) from the air within the hood (1) or as a mixture of air within the hood (1) and of dry replacement air. For air ducts (11A,11B) are used horizontal air ducts (11A,11B) extending the length of the hood (1) and on which have been disposed blowing nozzles (8A,8B), of which the blowing direction is obliquely towards the inner surfaces of doors (12A,12B) or equivalent of the hood (1) adjacent to them or below them.

Dependencies are inferred from the claim text.