Meaning
International reference document establishing general rules for evaluating and expressing uncertainty in measurement is widely known as the Guide to the Expression of Uncertainty in Measurement. In the polymer testing sector, iso iec guide 98-3 defines how laboratories calculate the total uncertainty of mechanical, thermal and rheological measurements of plastic materials. It ensures that reported values for properties like heat deflection temperature can be compared across different testing laboratories.
Rheological Consistency
Melt viscosity of a polymer batch determines how easily it will fill the cavities of a complex injection mould. When characterizing viscosity using capillary rheometry, applying the methodology of iso iec guide 98-3 helps the chemist identify the primary contributors to measurement variation, such as transducer drift and die temperature fluctuations. This detailed analysis allows the laboratory to report the melt flow rate with a high level of confidence.
Production Defect
Incorrect cavity filling and part flashing occur when the resin viscosity drifts outside the process window. Using the calculation methods of this metrological guide, moulders establish precise limits for their incoming quality control testing. This precaution ensures that the variation in test results is not confused with actual material drift, reducing the occurrence of short shots or sink marks in production.
Customer Trust
Providing certified test reports is a common requirement for medical-grade polymer applications. Aligning testing procedures with this guide ensures that the reported measurement uncertainty is accepted internationally, simplifying regulatory approvals.
