FIELD: production of chemical filaments, woven and nonwoven materials in chemical, textile and light industry. SUBSTANCE: elongated flat material (corrugated and noncorrugated), cord laid onto substrate or subjected to tension, film, nonwoven material are subjected to continuous contact-free thermal treatment in pipeline provided with inner reflective surface. Apparatus has device for holding the material, device for moving gaseous medium within pipeline and heating members secured along focus lines of pipeline cylindrical surfaces. Pipeline surfaces at both sides of material are composed of portions joined one with another and repeated at least twice. These portions may be made in the form of elliptical, hyperbolic or parabolic cylindrical surfaces arranged so that their focus lines are extending in plane of material and oriented along or transverse to pipeline. Dividing walls positioned in pipeline, as well as material holding device, are provided with channels for removing or supplying different substances from or into pipeline. EFFECT: increased efficiency, simplified construction and enhanced reliability in operation. 4 cl, 6 dwg
