1. Turn on the power, and the temperature controller and timer display lights will be on.
2. Inject the frozen medium (generally industrial ethanol) into the cold well, and the injection amount should ensure that the distance between the lower end of the gripper and the liquid level is 75 ± 10 mm.
3. Clamp the sample vertically on the holder. The clamp should not be too tight or too loose to prevent the specimen from deformation or falling off.
4. Press the holder to freeze the sample, and start the timing control switch (or press the stopwatch) to time. The freezing time of the sample is 3.0 ± 0.5min. During the freezing period, the temperature fluctuation of freezing medium shall not exceed ± 1 ℃.
5. Lift the lifting clamp to make the impactor impact the sample within half a second.
6. Take down the sample, bend the sample to 180 ° according to the impact direction, and carefully observe whether there is any damage.
7. After the sample is impacted (only one impact is allowed for each sample), the temperature of the frozen medium shall be increased in case of damage, otherwise, the temperature of the freezing medium shall be reduced and the test shall be continued.
Through repeated tests, the minimum temperature for at least two specimens not to be damaged and the maximum temperature for at least one specimen to be damaged are determined. If the difference between the two results is no more than 1 ℃, the test is over.
Yangzhou jingzhuo experimental Machinery Factory is specialized in material test and research. It can test rubber, plastic, metal, pipe, copper, paper, building materials, textile, cable, spring, wood and so on. Tel: 15371261889
