Automatic calorimeter maintenance

1. Always add water manually. The standard requires that the external cylinder water quantity be more than 5 times more than the internal cylinder water quantity, because the instrument will evaporate a part of water during idle time and during the test, and a part of water (about 2g each time) will be brought out when the oxygen bomb is removed during the test, and the lost water In the end, the water tank calorimeter will be reduced. As time passes, the outer tube will be short of water and the heat capacity will change. Some calorimeters will also reduce the amount of water in the inner cylinder, which will cause the inner cylinder to fail to meet the requirement of less than 1g per error. Therefore, depending on the size of the calorimeter, it is necessary to recharge the calorimeter from time to time.

2. Check the instrument accuracy with standard coal samples. When the accuracy of the instrument deviates, it should be analyzed. If it is not a test operation problem, it should be immediately reheated. Check the accuracy of the instrument as far as possible without using benzoic acid, such as the use of benzoic acid should be as hot as possible so that benzoic acid should be as hot as possible so that the quality of benzoic acid is 0.7-0.8 grams, due to the temperature rise and heat capacity generated by 1 gram of benzene squaric acid Consistent, its temperature error detection is out.

3. Control the ambient temperature. Theoretically speaking, the greater the difference between the water temperature of the outer cylinder and the ambient temperature, the greater the amount of heat exchange, and thus the greater the heat loss of the inner cartridge. Assuming that the heat capacity of the instrument is 10,000 J/K, the correction value will deviate. 0.01K, the heat will deviate from 100J/G, plus other factors, the calorific value will deviate even larger. From an experience point of view, the temperature of the outer cylinder will increase by 0.1 to 0.2 per one calorific value. If 10 samples are continuously made, the outer cylinder will have to rise. When the ambient temperature rises, the green manure will, according to experience, send the normal test value to the routine. It will be on the high side, so keep a good environment and ambient temperature, it is very important to ensure that the calorific test results show accuracy. 4. Change the external bobbin water regularly. Water cartridges can be mixed with impurities for a long period of time, resulting in a change in the calorimetric heat capacity. Generally, the number of visual tests can be changed from 6 months to one year. However, if there is any dirt in the water, change the water immediately to avoid the normal operation of the water pump and the valve.

5. After the end of each experiment, the calorimeter cover should be opened to accelerate the water temperature in the lower cylinder. If the calorimeter upper cover is not used for a long time, the inner cylinder is contaminated.

6. Do not disassemble the instrument; do not start the pump when there is no water; intermittently use or standby instrument should always be powered on for waste sample test to prevent the valve and the pump from being inflexible or rust after long-term deactivation.

7. To keep the inner cylinder clean. Ignition electrode should always be wiped to avoid surface fouling and cause ignition failure. The stirrer fan blade should be cleaned to prevent the deposition of the above-mentioned dirt and wash into the inner cylinder.

8. Pay attention to protect the temperature probe and avoid collision. The probe is usually made of pure platinum wire wound on a glass rod. The surface is covered with a thin layer of glass. Once the glass is crushed, it will seep water, causing the resistance of the platinum resistor to change. At this time, the temperature display value will jump and the temperature measurement will not be accurate. At this time, the test should be stopped immediately, and maintenance and replacement should be carried out.

9. During use, be careful not to spill water on the edge of the inner cylinder to prevent the inner and outer cylinders from entering the water and causing the parallel to be out of tolerance.

10. With Windows version monitoring software, the computer can not run other programs (including virus real-time monitoring program, screen saver, etc.) at the same time when testing, so as not to interfere with the test process and affect the test results.

11. Elastomers should be subjected to a hydrostatic test of 20.0 MPa on a regular basis. After each hydrostatic test, the use time of the oxygen bomb should not exceed 2 years. Usually, attention should be paid to the structure related to the strength of the oxygen bomb, such as the connection between the cartridge and the connecting thread, the inlet valve, and the electrode and the oxygen warhead. If significant wear or looseness is found, it should be repaired and used after passing the hydrostatic test.