Measuring and testing – Vibration – By mechanical waves
Patent
1992-09-29
1995-07-18
Williams, Hezron E.
Measuring and testing
Vibration
By mechanical waves
73 5441, 73599, 73644, G01N 2918, G01N 2920
Patent
active
054331129
ABSTRACT:
A method and apparatus for ultrasonically characterizing a polymer melt flowing in a predetermined direction between two opposed parallel surfaces spaced from one another to define a gap filled with polymer are disclosed. Ultrasonic pulses are propagated through the polymer melt between the two surfaces in a direction normal to the direction of flow for interaction with the polymer, the ultrasonic pulses having a duration such as to prevent successive echoes from overlapping with one another while reverberating between the two surfaces. The time delay between two echoes exiting from the polymer melt and generated from each pulse having interacted with the polymer is continuously monitored while simultaneously monitoring amplitude variations of the two echoes, to provide output signals representative of ultrasonic velocity and attenuation in the polymer melt. These output signals are processed to obtain data comprising ultrasonic velocity and attenuation values measured simultaneously as a function of time. The data is then processed to derive quantitative information relating to viscoelastic properties, structure or composition of the polymer, which can be used as input data in a closed-loop process control system.
REFERENCES:
patent: 4015470 (1977-04-01), Morrison
patent: 4509360 (1985-04-01), Erwin et al.
patent: 4559810 (1985-12-01), Hinrichs et al.
patent: 4677842 (1987-07-01), Piche
patent: 4754645 (1988-07-01), Piche et al.
patent: 5170667 (1992-12-01), Takeuchi et al.
Hunston, Donald L., "Determination of the High Frequency Viscoelastic Properties of Polymers Using Shear Mode Strip Delay Lines", pp. 201-210.
William H. Press et al., "Numerical Recipes", Cambridge University Press, 1986, pp. 381-416.
R. Gendron et al., "Material Characteristics Oriented Computer Control of Extrusion-Part 1", Conference Proceedings of ANTEC'91: 49th Annual Technical Conference of the Society of Plastics Engineers, May 1991, vol. XXXVII, pp. 958-963.
R. Gendron et al., "Extruder Control via On-Line Product Characteristics Monitoring", Program and Abstracts of the 7th Annual Meeting of the Polymer Processing Society, Apr. 1991, pp. 252-253.
Dumoulin Michel
Gendron Richard
Hamel Andre
Piche Luc
Tatibouet Jacques
Ashraf Nashmiya
Williams Hezron E.
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