Measurement Error
Calibration inaccuracy in optical measuring devices occurs when temperature changes or dissolved solids alter the light refraction angle. This refractometer drift leads to incorrect readings of sodium hydroxide concentration in the alkaline baths used for textile processing. The resulting errors can cause operators to add too much or too little chemical to the mercerizing line.
Thermal Sensitivity
The presence of dissolved organic compounds, such as hemicelluloses extracted from cotton, coats the optical prism and distorts the light path over time. While automatic temperature compensation reduces thermal effects, refractometer drift still occurs when the instrument operates in highly alkaline, high-temperature environments. Regular physical cleaning of the prism surface is necessary to maintain optical clarity.
Calibration Maintenance
Mill technicians must implement daily zero-point calibrations using distilled water to compensate for the gradual deviation of the sensor. If refractometer drift is not corrected regularly, the calculated concentration of the lye bath can deviate by several grams per liter. This discrepancy undermines the accuracy of the automated dosing system and can lead to under-processed yarn.
A systematic calibration protocol ensures that the optical sensors remain reliable during continuous production runs.
Process Consequence
Maintaining stable sensor readings guarantees that the mercerization process remains within its specified chemical limits. Correcting refractometer drift avoids the costly reprocessing of unevenly treated fabrics.
