1. Main purpose and working principle
Liquid specific gravity balance is one of the measuring instruments. It can be used to measure the specific gravity of liquids in laboratories of chemical industry departments and scientific research departments. The balance has a standard measuring hammer volume (5cm3) immersed in the liquid to obtain buoyancy to make the beam out of balance, and then place various quantitative riding weights (weights) in the V-shaped groove of the beam to restore the balance of the beam, and the balance can be quickly corrected. Measure the specific gravity of the liquid.
2. Structural diagram of the balance
3. Main technical parameters
1. Measuring hammer volume: 5cm3 Measuring hammer standard temperature: 20℃
2. Measure the maximum specific gravity of the liquid: 2.000
3. Accuracy: 0.001
4. The expression form of liquid specific gravity: δ20
5. Dimensions: 240mm×90mm×280mm
6. Weight (net weight): 1kg
4. Balance installation and adjustment
After unpacking and unpacking the balance, clean it carefully, especially the blades and agate knife holders, which should be wiped clean with a handkerchief or soft brush. It is forbidden to use rough cloth and hard brush, and it must be prevented from being scratched and damaged.
1. The balance should be installed in a room with normal temperature (about 20°C). It should not be heated or cooled in one direction, and should be protected from airflow, vibration, strong magnetic source, etc., and installed on a firm workbench.
2. When using, take out the various parts in the box in sequence. Wipe the measuring hammer, elbow thermometer and glass measuring cylinder with alcohol, then loosen the set screw of the pillar, raise the bracket to an appropriate height and screw it on the small hook. Rotate the level adjustment foot to align the pointer tip on the crossbeam with the two tips of the bracket pointer to show balance. If the balance cannot be adjusted, first loosen the small positioning screw on the balance adjuster, and then turn the balance adjuster slightly until the balance stops. Then tighten the middle positioning screw to prevent loosening.
3. Remove the equal weight and replace it with a whole set of measuring hammers. At this time, the balance state needs to be protected, but an error of ±0.0005 is allowed.
4. After the balance is installed, check whether the position of each component is correct, and the installation can only be considered complete after the beam swings normally.
5. Balance use and maintenance
The balance, like other measuring instruments, requires careful maintenance and strict compliance with the rules for the installation and use of the balance.
1. The balance should be adjusted before use.
2. Put the liquid to be tested into the glass measuring cylinder for testing.
3. Immerse the measuring hammer into the liquid in the glass measuring cylinder, and the beam loses balance at this time;
Various riding codes should be added on the V-shaped groove and the small hook to restore balance to the balance. At this time, the sum of the riding codes on the V-shaped groove of the beam and the small hook is the specific gravity value of the measured liquid.
Reading method:
The relationship between the V-shaped groove on the beam and various minimums is decimal.
By analogy, for example, when the measuring hammer is immersed in water at 20°C, various riding codes are added to balance the beam. The seventh, sixth, fourth, and second slot positions can directly read the specific gravity at that time as 0.7642 (see picture).
The temperature can be read directly in Celsius from the elbow thermometer inside the glass measuring cylinder (convert when it is inconsistent with the standard temperature).
4. The liquid measurement is completed. All the riding codes on the V-shaped groove of the beam and the small hook should be removed, and they cannot be left on the V-shaped groove of the beam and the small hook.
5. When the balance needs to be moved, the easy-to-separate parts, components and beams should be disassembled separated to avoid damage to the knife.
6. According to the frequency of use, cleaning work and measurement performance verification should be carried out regularly. When the balance is found to be distorted or in doubt, it should be stopped before the fault is eliminated, and it can be used only after the repair and verification pass.
