New technology breakthrough and better performance (QBZY series automatic surface / interface tensiometer)

New technology breakthrough performance is more excellent

QBZY series automatic surface / interface tension meter

At present, there are many manufacturers of surface / interface tensiometers produced in China, and the models of surface / interface tensiometers are more diverse. However, apart from the series of surface / interface tensiometers produced by Shanghai Fangrui Instrument Co., Ltd., none of them have " "Automatic accuracy calibration" is an internationally advanced and very practical technology.

The so-called "accuracy automatic calibration" refers to the automatic correction of the overall error of the instrument test standard samples, using double distilled water and pure ethanol as the standard, the error from the literature value can reach: ≤ ± 0.2mN / m (QBZY-1 Type), ≤ ± 0.04mN / m (QBZY-2 type), ≤ ± 0.01mN / m (QBZY-3 type).

All surface / interface tensiometers generally have full-scale calibration. No matter what method is used, it can only calibrate the circuit part of the instrument, that is, replace the measured value of the sample with a standard weight. Full-scale calibration is very necessary for the instrument, but it is not comprehensive: an instrument with a full-scale calibration does not mean that the actual test sample is necessarily accurate. This is because the full-scale calibration does not take into account the test error of the sensing element-platinum plate or platinum ring. Platinum plates or platinum rings have strict size and processing requirements. Platinum plates require flatness, a certain surface roughness, can be fully wetted with liquid, and the contact angle is zero; platinum rings require platinum wire diameter, circumference, etc. to meet In addition to the relevant standards, a standard circle is also required.

The instrument should be carefully adjusted when it leaves the factory, and it should be able to reach the specified factory standard, but how about using it for a while? How many will encounter the following situation:

1. The surface of the platinum plate has been worn, scratched or the dimensions have changed slightly

2. The platinum ring is deformed, no matter how it is shaped, it is not round or the bottom is uneven

3. No matter what method is used, the platinum plate or platinum ring is not clean.

The occurrence of the above-mentioned situation will definitely bring greater errors to the test accuracy, and the impact will be greater when the test accuracy is high. To solve this problem, according to the past practice, only to re-purchase platinum plate or platinum ring. Now with the function of "Automatic Accuracy Correction", this problem can be completely solved after only recalibrating the instrument by testing twice-distilled water and pure ethanol. This improves the test accuracy of the instrument and reduces the cost of the instrument.

When performing this calibration, the standard sample needs to be thermostatted at 20 ° C. According to the literature, the surface tension value of double distilled water at 20 ° C is 72.75 mN / m, and the surface tension value of ethanol at 20 ° C is 22.3 mN / m. After a simple operation, the accuracy of the instrument can be corrected to the precise state at the time of shipment, which can fully meet the requirements of the technical parameters of the instrument, that is, ≤ ± 0.2mN / m (QBZY-1 type), ≤ ± 0.04mN / m (QBZY-2 type), ≤ ± 0.01mN / m (QBZY-3 type).