Density calibrator

Hydrometer calibration system

The DM-01 is an automated hydrometer calibration system based on Cuckow’s method or hydrostatic weighing. A temperature bath with stability and uniformity better than 0.01K is located on a base plate whose vertical position is adjusted automatically. A cylinder with calibration liquid inside is immersed into the bath so that the temperature of the calibration liquid is extremely stable up to 0.004K.

The hydrometer to be calibrated is immersed partially into the calibration liquid and suspended to a mass sensor, such as balance or mass comparator, which is separately fixed on a vibration free framework. By adjusting the position of the bath, the length or the scale of the hydrometer immersed into the calibration liquid is adjusted precisely, and the mass difference of the hydrometer in the liquid and in the air is measured by the mass sensor. Based on the mass difference, the hydrometer is calibrated with specified uncertainty which is influenced by the solid reference, the temperature stability, the calibration liquid, the atmospheric pressure, the humidity, and so on.

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Liquid density CRMs characterization system

The DRM is a hydrostatic weighing apparatus for characterization of liquid density certified reference material (CRM) that is critical for the calibration of densimeters.

The liquid density is traced to the SI units of length and mass.

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Inline densimeter and refractometer calibrator

The POD-M2 is designed to calibrate or verify the inline densimeter while ensuring appropriate operational conditions.

The calibration fluid is circulated at specified velocity in a calibration module whose temperature is strictly stabilized to ensure accurate measurements. The sensing area of the densimeters are fully immersed in the fluid. Due to a unique design, the calibration fluid has no bubbles.

The POD-M2 has a laboratory version and a portable version. The portable version can be used both in laboratory and on site calibration.

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