Apparatus to supply steam including steam evacuation

Claim 1

Apparatus to supply steam to a paper sheet moving beneath it, the apparatus having a leading edge and a trailing edge relative to sheet direction and comprising: a header; means to supply steam to the header; a chamber adjacent to the header; means dividing the chamber into a plurality of compartments in the cross machine direction; a pipe connecting each compartment to the header to supply steam from the header to each of the plurality of compartments, an inlet for each pipe in the header, an outlet for each pipe in each compartment, a valve control associated with each pipe and a piston extending from the valve control to the pipe inlet whereby control of the steam supply from the header to the individual compartments of the steam chamber can be achieved; a heating zone defined beneath the chamber to be generally adjacent to the paper sheet when the apparatus is in use; outlets in the chamber to permit steam to pass from the chamber to the heating zone; exhaust manifolds positioned adjacent to and substantially coextensive with the leading edge and the trailing edge of the apparatus whereby excess steam vapour may be drawn away from the heating zone.