Ultrasonic HDPE/LDPE bottle wall-thickness measurement system.
Conveyor autofeed and autonomous operation enhances laboratory testing efficiency and productivity.
Greater precision versus handheld hall-effect methods.
Excellent wall-thickness performance without the limitations of handheld gages.
Data output compatible with most commercial SPC software packages.
For over 15 years, AVID customers have requested an automated wall-thickness measurement system for polyethylene (HDPE/LDPE) bottles.
A wall-thickness solution for PET bottles has long been available using nIR technology, as demonstrated in the ABTIS / I-TES systems from AVID. However, nIR methods have significant limitations in applications involving polyethylene materials, generally because of 'contaminants' and additives that block the nIR wavelength necessary for consistent measurement. Terahertz (“TE” or “Tz”) sensors are able to measure PE wall-thickness, but have been prohibitively expensive. Additionally, terahertz technologies have demonstrated performace only along straight and flat surfaces, a significant limitation given the known needs of packaging manufacturers.
PE bottle manufacturers have therefore relied upon thickness checks conducted with a hall-effect micrometer, or “MagnaMike.” While the use of this tool is commonplace throughout the packaging industry, measurements via Magnamike are known to be non-repeatable and prone to user error.
For several years, AVID engineers have been developing the U-TES-B, a fully automated, accurate, and repeatable HDPE/LDPE bottle wall-thickness measurement system. The system uses the long-successful AVID auto-feed system featuring a linear conveyor and load arm, as used in the AVBIS 3000C, AVMS 2000, and AVMS 2000 products.
In normal operation, the user loads a set of bottles onto the linear conveyor, and selects the part ‘recipe’ applicable to that specific bottle from the part library. The recipe includes a preprogrammed number of points to be measured around the bottle and the positions of those points. The user indicates the number of bottles on the conveyor to be measured. At this point, the system will run completely automatically, availing the user for other laboratory tasks.
Bottles are loaded quickly and efficiently to the rotary inspection platform. A six-axis robot arm maneuvers the testing probe to programmed measurement points. The robot’s range of motion permits measurements along the vertical sidewall, shoulder regions, and up to -15° from the vertical sidewall for “heel” regions.
Cycle time varies with the number of points to be measured. A bottle with 16 points of measurement at 90° intervals of rotation takes approximately 1.5m to complete. In the event a point produces an aberrant value, an automatic point ‘retest’ option repositions the ultrasonic probe and attempts to test position again reducing data errors. Gage repeatability and reproducibility studies conducted on HDPE bottles yield results typically between 6%-12%, based on typical industry tolerances.
At the time of this writing, the system is in final development and will be available to HDPE/LDPE manufacturers starting in Q1 2021.
Please contact AVID Corporation for more information on this new and exciting product!
Plastic Bottle Wall Thickness
Plastic Bottle 'Heel' Thickness
Bottle Weight (with scale option)