GB486447A - Improvements in or relating to heating, cooling or drying cylinders - Google Patents

Abstract

A hollow heating or cooling cylinder of cast metal is provided with a number of tube coils 11, embedded in its circumferential wall during casting, for the circulation of heating or cooling fluid, each coil having an inlet and outlet pipe 12, 13 extending to inlet and outlet passages located at or near the axial centre of the cylinder. These passages are arranged in the axial mounting of the cylinder which may be rotated, by subdividing an axis 17 by means of a wall 18 into the passages 19, 20 which are connected to the inlet and outlet pipes respectively by means of flexible pipe connections 14 and 15. The latter may be attached to a detachable boss 25, the mounting as a whole being attached to the end wall of the cylinder by a flange 16. A similar, undivided axis 17a is provided at the opposite side of the cylinder. In a modification, the subdivided axial shaft 17 extends completely through the cylinder. The turns of the coils 11 may be intercalated in any desired manner to facilitate the equalizing of the temperature over the cylinder surface. The fluid circulation in each coil may be separately controlled to regulate the temperature gradient along the cylinder surface. In a film dryer, in <PICT:0486447/III/1> <PICT:0486447/III/2> which heating or cooling liquid may be circulated through the coils, the cylinder picks up liquid to be dried from a trough 26, Fig. 2, and the dried material is removed by a scraper 28. The trough may be heated by a coil 27 to prevent incipient congelation, and the scraper may be adjusted by slight rotation of its mounting which comprises a spindle 30. A valve in the feed pipe 34 to the trough may be automatically opened or closed by the rotation of the cylinder through a cam rotating in unison therewith, the cam operating a link-and-crank mechanism connected to the valve.