Abstract: The process and device are intended for controlling the molding of a container during the manufacture of containers from a thermoplastic material. At least two previously injection-molded preforms are temperature-treated and delivered in succession to at least one blow station for blow molding of the preforms into containers. In order to compensate for nonuniform temperature distribution in the material of the preforms relative to one another, at least one blow parameter during molding of the preforms into containers is specified in a fashion that differs from one to the next. The differing specification is made in such a manner as to compensate for the nonuniform temperature distribution so that containers with approximately identical spatial distribution of wall material, orientation properties, and crystallization characteristics exist when the blow-molding process is finished.

Abstract: Blown or flat-extruded plastic film having systematic plus or minus errors in thickness along the width of the film have a thickness profile measured and the measured profile is fed to a computer which controls the extruded film or tube from which the film is blown so that the foil thickness will be increased between regions of plus-thickness error or decreased in sense between regions of minus-thickness errors, or both alternatingly, so that the resulting coil is cylindrical with significant precision and without the need to move the blowing head or tube flattening device.