The importance of calorimeter calibration

As a key device for accurately measuring heat, calorimeters are widely used in coal, chemical, electric power and other industries. The accuracy of their measurement results is directly related to product quality and production safety. Therefore, regular calibration of calorimeters is a necessary measure to ensure reliable data.

Preparation before verification

1. Control of environmental conditions: The verification should be carried out in an environment with stable temperature (15-30 ° C), suitable humidity (≤ 80%) and no strong electromagnetic interference to avoid environmental factors interfering with the verification results.

2. Preparation of reference materials: The standard benzoic acid that has been certified by the state and has traceability is selected, and its calorific value is known and stable. It is the core reference material for calibrating calorimeters.

3. Instrument status inspection: Carefully check the oxygen bomb, inner cylinder, agitator, temperature measurement system and other components of the calorimeter to ensure that the instrument is not damaged or leaked, and all functions are normal.

The specific operation steps of verification

1. Installation and loading: Press the standard benzoic acid into a sheet, weigh it accurately and put it into the oxygen bomb crucible. Install the ignition wire to ensure good contact with the benzoic acid sheet, then put the oxygen bomb into the inner cylinder of the calorimeter and connect the electrodes.

2. Parameter setting: According to the calorific value of standard benzoic acid, accurately set the relevant parameters of the calorimeter, such as heat capacity, ignition temperature, etc.

3. Ignition and measurement: Start the calorimeter and measure the ignition. When the measurement process is over, record the temperature change data, and the instrument will automatically calculate and display the measurement results.

4. Repeated measurement: To ensure the accuracy of the results, repeat the above operation at least three times, and take the average of multiple measurement results as the final measurement value.

Judgment and Processing of Verification Results

Compare the average value of multiple measurement results with the calorific value of standard benzoic acid. If the error is within the specified range (such as ± 0.2%), determine that the calorimeter is qualified; if the error exceeds the range, check whether the instrument is faulty and re-calibrate until the result is qualified.

Maintenance and records after verification

After the calibration is completed, clean the instrument in time and properly store the reference material. At the same time, record the calibration process, results and instrument status in detail, and establish a calibration file to provide reference for subsequent calibration to ensure that the calorimeter is always in an accurate and reliable operation state.