Production of plastics sheet material

摘要

A sample strip (80) of plastics sheet is laid on a table (81) of a bed (83) having tracks (82) on which the table is mounted. The table (81) has a pipe network (90) supplied from heating/cooling fluid lines (91,92) to provide a heat exchange surface. The table is moved into a heated position underneath two banks (84,85) of infra red heaters. The sample (80) is then heated from below and on top for a preset period. After heating, the table (81) with the heated sample is removed and the dimensions of the sample (80) are compared with those of the sample prior to heating. A plastics sheet forming process may be adjusted accordingly.