PETpla.net Insider 09 / 2016

MATERIAL / RECYCLING 40 PET planet insider Vol. 17 No. 09/16 www.petpla.net Figure 6 How inherent viscosity affects yield point and volume expanson (a) low IV (b) higher IV (c) highest IV The solution A considerably more detailed overview of a bottle’s mechanical performance can be achieved by analysing each of the properties previ- ously mentioned; taking bottle testing beyond single burst point measure- ment. Torus’ B303 Burst Gauge, see Figure 7. offers this functionality in a robust and user-friendly design. Bottles are loaded individually into custom location discs. Once secured the burst routine can start behind a locked, waterproof safety door, provid- ing a controlled test environment. A user-definable test procedure is per- formed and live graphs are updated on screen. Additional numerical and graphical results are displayed when the test is complete. Figure 7 Torus’ B303 Bottle Burst Gauge Examples of the user-definable test modes include Burst Mode & Hold Mode. Burst mode is the simplest of the modes available within the gauge software. A pressure ramp rate can be set by the user along with a maxi- mum pressure, or it can be selected to ramp until burst. This can be used to find all of the mechanical proper- ties described in this article, highlight- ing the pressure and volume at both yield and burst points along with data describing the volume expansion. Hold mode allows holds to be added into the tests in order to rep- licate states the bottle will endure during its lifecycle. Up to three holds and their relative durations can be set at user defined pressures, see Figure 8. Figure 8 Pressure hold graph New PET aerosol testing Furthermore, Torus Measurement Systems have a newly developed high pressure burst gauge designed for testing more robust PET aero- sol bottles. The gauge holds all the capabilities of the current B303 gauge with the added benefit of testing up to pressures of 40 bar, doubling the cur- rent gauge limit. www.torus-group.com