Cooling sheet of extruded thermoplastic and paper waste - uses endless steel band to support sheet while cooling

摘要

A plant for making sheets from thermoplastic and paper waste by extrusion has a cooling section consisting of an endless steel band (12) running round rollers (13a,13b). The band has a roller pair (14a,14b) and a top roller (15) over the rear band roller (13a). The cooling band (12) is followed by double sided adhesive application and the laminating of cover layers on both sides of the sheet. Pref., an extruder (10) feeds a sheet die (10a) which is inclined downwards towards the steel band (12) on which the sheet is deposited. The extruded sheet is compacted by a roller pair (14a,14b) and sized accurately by a roller (15). Cooling can be assisted by a water spray and is completed on a roller conveyor (16) which follows the steel band (12). Adhesive is applied through two slit nozzles (17a,17b) and cover sheets from coils (21a,21b) are laminated on both sides by rollers (23a,23b). The sheets are then edge trimmed (11a), cut (11b) and stacked (24). USE/ADVANTAGE - For cooling thick sheets made by extruding thermoplastic and paper waste. The freshly extruded sheet is supported by the steel band until it has cooled enough to be self-supporting so that processing breaks are avoided.