Abstract: Process and apparatus for measuring variations in a stream of material, such as thickness in a strip from a mill. A radiation source and detector are positioned at a gauging station. The stream of material moves past the station providing an electrical signal varying as a function of material at the station which signal includes a lower frequency component, a higher frequency cyclical component, and a higher frequency noise component. A circuit for providing a thickness output varying as a function of the lower frequency component of the signal, and a circuit providing an output indicating chatter varying as a function of the higher frequency cyclical component. Digital and analog versions are disclosed.

Abstract: An extrusion line for producing rubber tire tread. Method and apparatus for continuously controlling extrusion line operation to maintain a predetermined length and weight for the finished product. Sensors for unit weight, extruder speed and swell, extruder load, extrudate temperature at the extruder and at the skiver, and conveyor speeds, signal conditioning circuits, and controls for take away conveyor speed, extruder speed, unit weight and skiver length.

Abstract: Apparatus and method for measuring thickness of sheet material, particularly in a rolling mill, and controlling a roll stand. An X-ray florescence analyzer for determining the components of the sheet material, a radiation thickness gauge with a calibration system for gauging material of varying composition, and a computer for calculating a calibration signal for the thickness gauge based on the output of the analyzer, with the thickness gauge output providing a measure of the thickness of the sheet material at the gauge and a control signal for controlling the roll stand.

Abstract: Apparatus and method for continuous measurement of thickness of a sheet at a rolling mill or the like without contacting the sheet. A system directing radiation through the sheet in two energy bands and providing a measure of change in composition of the material as it passes the thickness gauging station. A system providing for changing the absorption coefficient of the material in the thickness measurement as a function of the change in composition so that the measured thickness is substantially independent of variations in composition.

Abstract: Apparatus for measuring the thickness of the plastic film of a blown film machine, making the measurement adjacent the extruder die without contacting the film. A radiation source and detector spaced from one side of the plastic film and a metal member spaced from the other side, with the detector receiving fluorescent x-rays from the metal member produced by source photons and receiving back scattered source photons from the film and the metal member, with both the fluorescent x-rays and the scattered photons producing indications of thickness.