GB1105239A - Apparatus for heat treatment of fibrous sheet materials - Google Patents

Abstract

Apparatus for the heat treatment e.g. steam treatment, of continuous lengths of fibrous sheet materials comprises a compressible roll 2 urged against a perforated drum 1 to form an extended nip zone, a stationary fluid treatment chamber 3 within the drum 1 and communicating with the drum perforations in the region of the nip, seals 4 mounted on the chamber 3 and urged against the inner surface of the drum, and exhaust means 5 in the region of the nip to withdraw escaping fluid. Cooling means such as a water passage 6 may be provided within the roll 2 which preferably comprises a hard shell 46 with an elastomeric covering material 49. The seals 4 preferably made of a porous carbon composition impregnated with a fluorocarbon resinous material are mounted in recesses formed in the chamber 3 walls and urged against the drum by means of springs 28. Treatment fluid is supplied to the chamber via pipe 7 and any escaping fluid is withdrawn through <PICT:1105239/C6-C7/1> the ducts 5. The material to be treated e.g. non-woven fabric webs or paper-like material may be led through the nip on a foraminous belt 65. The compressible roll may be of pneumatic structure, having provided within, an outer membrane, elongate tubular elements extending in the axial direction of the roll or toroidal elements e.g. tyres arranged side-by-side along the roll length, the tubular or toroidal elements being expanded to pack tightly against one another, Figs. 2 and 3 (not shown).