Realization of laser on-line measurement system to high temperature melt diameter

摘要

Extrusion swell of polymer is a key factor to analyze the polymer elastic behavior. Then we have to measure the diameter after the melt is extruded to acquire the extrusion swell. At this special circumstance it is very difficult to get the melt diameter because the melt temperature is very high (over 100 ℃) and it is very easy to distort. After analyzing the deficiency of traditional measuring methodologies, this paper presents a new framework developed for non-contact, high speed, high precision, on-line measurement to polymer melt diameter. In this framework, BRABENDER laser scan micrometer for round strands instruments is used to change a target diameter into an analog voltage signal, then the analog voltage signal is acquired and converted into a digital signal by using PCL-812PG data acquisition card. This digital data can be converted into the melt diameter according to a calibration. A software using Delphi language is designed to control the whole data-acquisition process, such as: setting the data sampling frequency and time, calculating the final diameter, displaying the sampling data.