INNOVATIVE MILLIMETER WAVE TECHNOLOGY FOR MEASURING THE PIPE WALL THICKNESS EARLY IN THE EXTRUSION PROCESS
Christian Schalich
# 2021 Amsterdam
Plastic pipes for infrastructure and building applications are precisely specified with regards to wall thickness and diameter. Pipe manufacturers use different measuring methods in order to ensure the required dimensional accuracy and maintain a constant high quality. This paper introduces a measuring system based on millimeter wave (radar) technology. It provides a non-contact, non- destructive, online measurement of wall thickness, inner and outer diameter, ovality, inner profile and sagging of plastic pipes during the extrusion process. One or more rotating transceivers continuously send and receive frequency modulated waves to ensure the monitoring of the wall thickness covering 360 degrees of the pipe circumference. The system is typically installed after the first vacuum tank in order to monitor the pre-cooled dimensions of a pipe. Its adaptivity to different materials allows for using this technology on all kinds of pipes made of polyolefines, flourpolymers and PVC in diameter ranges from 90 (optional 60) up to 3,200 mm with a min. wall thicknesses of 3.8 mm. For PVC this technology is able to measure even smaller pipes, starting from diameter 60 mm with a min. wall thickness of only 2.3 mm. The precooled 360° values of the wall thickness and diameter of the pipe are measured in order to evaluate the sagging effect of the material during the cooling process. These values help for a fast centering of the pipes and can automatically be controlled without delay to the minimum permitted nominal value. Due to a patented automatic determination ofthe material related refractive index, the operation of the system is intuitive and easy without any presetting of the material and its characteristics. The paper will outline this technology and the innovations that were developed in close cooperation with the demands of the market. The system as well as its functional principle will be introduced. By using this innovative technology, the start-up process is significantly facilitated and shortened. Thus, the production process is optimized, the highest quality of the pipe ensured and costs are saved. A Return on Investment (ROI) in less than 12 months is usually achieved.
https://www.pe100plus.com/PPCA/INNOVATIVE-MILLIMETER-WAVE-TECHNOLOGY-FOR-MEASURING-THE-PIPE-WALL-THICKNESS-EARLY-IN-THE-EXTRUSION-PROCESS-p1743.html
