Glass vessel calibration device

1、 Introduction to Glass Vessel Calibration Device:

(1) Product model and measurement range: LR-2 type 0.5-1000ml 31 pack.

(2) Materials

The capacity standard ball is made of colorless and transparent borosilicate glass blown, and after heat treatment, there is no concentrated stress present.

(3) The number of linear expansion systems meets the requirements of JJG20-89 standard.

(4) Allowable error value

Complies with the requirements of JJG196-90 "Verification Regulations for Commonly Used Glass Measuring Instruments".

(5. Verification medium: pure water.).

(6) The types, uses, and nominal capacities of standard glass measuring instruments are shown in the table:

2、 Method of using standard ball for glassware calibration device

1. Use a flat head standard ball to check the quantitative measuring instrument

Measuring the volume of liquid discharged from a measuring device, which is the nominal capacity, is called a volumetric measuring device, generally referring to burettes and straws. See Figure 1.

The verification steps are as follows:

(1) Select the standard ball corresponding to the measured quantity and standard.

(2) Connect the tested object and the standard ball to the piston, inject water, and adjust the zero position liquid level of the tested object. At the same time, adjust the starting standard liquid level of the standard ball. Then open the two-way three-way piston to discharge water from the tested object and inject it into the standard ball. When observing the water in the tested object reaching the calibration terminal, adjust the liquid level and close the piston. At this point, observe whether the lowest point of the standard ball liquid level is within the allowable error range to determine the accuracy of the measured instrument.

The above process is called the capacity comparison method, which can be used to calibrate the capacity of all B-class measuring instruments.

2. Use a pointed standard ball to check the quantitative input measuring device

Measuring the volume of liquid injected into a volumetric flask, when the liquid is in the volumetric flask, its volume is the nominal capacity, which is called a volumetric flask, measuring cup, measuring cylinder, etc.

The verification steps are as follows:

(1) Select the specifications of the tested quantity and standard glassware.

(2) After filling the standard ball with water, discharge it into the measuring device according to the specified water outflow time and circulation time. Then observe the lowest point of the liquid level to determine the accuracy of the measured quantity.

The above process is also known as the capacity comparison method, which can be used to calibrate glass measuring instruments such as measuring bottles, measuring cups, and measuring cylinders.

3、 Usage and maintenance

1. Before use, check whether there is any water leakage at the piston and various connections.

2、 Before use, check whether the standard ball body is clean. If there is water or uncleanliness inside the ball body, it should be cleaned with fuming sulfuric acid until there is no water hanging phenomenon.

2. Distilled water and clean water should be used for calibration.

3. After the calibration is completed, the water inside the standard ball should be drained to prevent long-term accumulation of water and the formation of scale.

4. Cleaning standard balls should not be done with strong acids, alkalis, or other chemical reagents.

5. According to JJG20-2001 "Verification Regulations for Standard Glass Measuring Instruments", a three-year cycle is required, and standard instruments must be sent for inspection.