Meaning
Series of physical steps taken to ensure a representative portion of material is suitable for accurate laboratory analysis. Effective sample preparation involves protecting the resin from atmospheric humidity and reducing particle size where necessary to improve moisture release. Pellets must be transferred quickly to sealed containers to prevent the absorption of water from the air.
Inconsistent techniques at this stage introduce measurable error into the final quality certificate.
Material Handling
Storage of the resin in moisture proof bags keeps the sample in the same state it was in when it left the dryer. Any delay in sealing the container allows the hygroscopic material to pull water from the room, which falsely inflates the reported moisture content.
Particle Reduction
Grinding or cutting large moulded parts increases the surface area available for moisture extraction in the oven. This step must be performed with minimal heat generation to avoid driving off the very moisture that the test is designed to measure.
Procedural Consistency
Uniformity in the way the sample is weighed and loaded into the analyzer reduces the variability between different operators. Using the same sample size and the same preparation tools ensures that the moisture data is comparable across different production shifts.
