The method for determining the yarn count of blended yarns essentially involves measuring the "length per unit weight" and converting this figure into a standard count; consequently, the process typically entails steps such as sampling, conditioning, weighing, and length measurement.
In practice, samples are first randomly selected from a batch in accordance with established protocols and subjected to conditioning under standard temperature and humidity conditions. This stabilizes the yarn's moisture regain, thereby preventing moisture content from skewing weight measurements. Next, the yarn is wound into a skein or unwound to a specified length (e.g., 100 meters or a standard skein length) and weighed using a precision balance.
Once the length and weight data are obtained, the yarn count is calculated using either the English Cotton Count (Ne) system or the Tex system. For instance, the English Cotton Count (Ne) is typically derived by calculating the number of 840-yard lengths per unit of weight. To enhance accuracy, laboratories generally perform multiple tests and calculate the average value; additionally, instruments such as the Uster tester are often used to analyze yarn evenness, ensuring the stability and reproducibility of the results.