Pendulum damping hardness tester

1、 Purpose:

QHD typePendulum damping hardness testerIt is designed and manufactured according to professional standard ZBN72020 and with reference to international standard ISO1522.

This instrument is used for sampling tests of paints, varnishes, and related products to determine the film hardness of paints, varnishes, and related products.

2、 Technical indicators:

Konig Pendulum

Total weight of the pendulum: 200 ± 0.2g

Swing period of the pendulum: 1.4 ± 0.02S

Glass value of swing: 250 ± 10S 178 ± 7 times (damping time times for the swing amplitude of the swing rod to shift from 6 ° to 3 ° on polished glass)

Persoz Pendulum

Total weight of the pendulum: 500 ± 0.1g

Swing period of the pendulum: 1 ± 0.001S

Glass value of pendulum: ≥ 420S, 420 times ± 14 times (damping time times for pendulum amplitude to shift from 12 ° to 4 ° on polished glass)

3、 Working principle and structure:

1. Working principle

The damping time of the swing rod on the paint film is expressed in seconds to indicate the hardness of the paint film. This is based on the principle that when the swing rod in contact with the paint film surface swings at a certain period, the softer the surface, the faster the swing attenuation, and vice versa. It is worth noting that there is no conversion relationship between the test results of Konig and Persoz swing rods with different structures, masses, sizes, and cycles. This is because the interaction between the swing rod and the coating also depends on the complex elasticity and viscosity of the coating. So in the product standard, only one type of pendulum is specified for measuring the damping time of a certain paint film.

Structure: The QHD type pendulum damping tester is mainly divided into the following parts.

Instrument stand: used to support test plates and swing rods, without a vertical support rod on the stand, and connected to a horizontal table with a working plane.

Swing rod: Konig or Persoz

Technical device that automatically records the number of required swing angles.

house

4Operation and usage:

preparation

1. WillPendulum damping hardness testerPlace the seat on a vibration free workbench and install the bottom corner screws and washers.

2. Connect the power cord of the counting device. Connect the photoelectric cell to the counting device using a connecting wire.

3. Install the two control handles in their respective positions.

4. Place the swing rod on the positioning pin of the workbench

(II)

1. Horizontal calibration of the instrument stand: Adjust the foot screws, observe the horizontal bubble, and calibrate it to be level.

2. Zero position calibration of the pendulum: After horizontal calibration of the instrument base, place the pendulum on the workbench to observe whether its tip is at the zero position of the scale. If it is not at the zero position, move the dial to align its zero position with the tip, and then tighten the dial fastening screw.

3. Position adjustment: Adjust the photoelectric cell to a position of 3 ° or 4 °.

Operation Instructions:

Connect the power supply of the counting device, turn on the power switch, and place the K/P swing conversion button in the corresponding position. After the experiment is completed, press the reset button to reset the counting display to zero.

Place the paint film on the test board onto the pallet on a horizontal workbench, and then rotate the pallet control handle to slowly lower the swing rod onto the test board.

Turn the starting handle and place it at 6 ° or 12 °, and use the swing bar stop device to stop the swing bar.

（4） Attention:

1. Apply quasi glass panels before each useClean thoroughly with ethanol and gasoline. Be careful not to scratch the surface of the glass.

2. Standard glass plates should be used regularly or before each test to verify whether the instrument meets the indicators of Konig pendulum 250 ± 10S: Persoz pendulum 420S or above. If it does not meet the requirements, the cause should be identified and eliminated to meet the requirements for testing.

3. It should be carried out at a relative humidity of 23 ± 2 ℃ (50 ± 5)%, and an instrument cover must be added when using the instrument.

4. Do not place the instrument in a well lit area for testing, in order to avoid the photoelectric cell being affected by external light, which may cause the automatic counting device to fail to count or even stop counting. The instrument should be placed in a place without strong light exposure.

5. Do not change the position of the upper pendulum of the Konig pendulum at will, as it is used to adjust the swing period of the K pendulum. Changing its position will also change the period of the K-pendulum. So when it is found that the period of the K-pendulum is not 1.4S. You can adjust the pendulum to reach 1.4S. Adjustment method: Let the pendulum swing on the glass plate, record the swing time 10 or 20 times with a stopwatch, and see if it is 14S or 28S. If not, adjust the position of the pendulum, and then record its swing time with a stopwatch. Repeat this process until the recording time reaches 14S or 28S, that is, the swing cycle reaches 1.4S.