Correcting apparatus enhancing volume measuring accuracy of small size bell jar and correcting method thereof

Abstract

The invention relates to calibrating device used to increase mini-size bell jar volumetric measurement accuracy. It includes impounding container, four exhaust valves, eight glass cock valves, globe, electric-magnetic stop valve, silicone tube, tubule needle head type drainpipe, small caliber weighing cylinder. The glass pipeline is the main structure of the whole device. The calibrating method includes the following steps: connecting the pipeline as the calibrating device; complementing water and exhausting gas; adjusting their flow quantity; elevating the ball jar; finishing the calibrating by n is not less than 6 times. The invention realize super mini-size bell jar metering volume (minimum volume reaches 10ml) high accuracy calibrating, increase flow measurement accuracy of the micro gas flow calibrating device used super mini-size bell jar as main standard.

Description

technical field [0001] The invention relates to a volume calibration device and a calibration method of a main standard of a bell jar type tiny gas flow calibration device and belongs to the technical field of gas flow measurement. Background technique [0002] The bell jar type gas flow calibration device uses the bell jar as the main standard device, and its flow measurement principle is as follows: the movable equal-section cylindrical bell jar and the fixed liquid tank form a variable-volume sealed air cavity, and the outer wall of the bell jar is set There are several shading sheets with different intervals to mark the measuring volume. During the movement of the bell jar, the shading sheets successively trigger the photoelectric switch fixed on the liquid tank to generate control signals, and control the timing device to complete the discharge (or inflow) of the bell jar. The measurement of the time Δt required for the gas volume ΔV is calculated by the formula (1) to ...

AI Technical Summary

Problems solved by technology

However, as the size of the bell jar decreases, the value of the relative uncertainty of the volume measurement will increase even under the condition of certain mechanical properties of the device. The direct reason for this result is the limitation of the existing conventional calibration method. Therefore, when calibrating the metering volume of small-sized bell jars used for micro-gas flow measurement, it is difficult to achieve a high level of accuracy with traditional calibration methods, which is why it is difficult for existing small-sized bell jars to achieve accuracy levels better than The main reason for level 1.0 (U≤1.0% (k=2)) level

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