Measuring corrugations in thin sheets - by checking flatness of table with gauge on transverse beam, positioning sheet on table, removing air beneath and repeating flatness tests

摘要

Corrugations in a web of material or a foil of rolled metal or extruded plastics are mesaured on a table with at least one gauging head. The gauge is used first to mesaure the corrugations in the table itself; the position of the material on the table is determined by at least one test transversely with the edges positioned; a number of measurements are then made longitudinally and the corrugations determined allowing for those of the table. The apparatus used can include foam rubber to press air out from beneath the material. ADVANTAGE - The method is accurate. It eliminates faulty measurements arising from variations in the material width or from incorrect positioning. All the measurements can be made mechanically.