In compliance with the technical requirements put forward in the production process, the type, model, measurement range and accuracy level of the instrument should be reasonably selected in accordance with the principle of economy.
1. Selection of instrument accuracy level
The accuracy of the instrument should be determined according to the maximum measurement error allowed in production. 。 When selecting, you should choose a pressure gauge with low accuracy and low cost as much as possible while meeting the production requirements .
2. Selection of instrument type
The general principle of selecting an instrument is to meet the requirements of the production process: when selecting specifically, three aspects can be considered:
Environmental conditions: such as the temperature of the environment, the strength of the electromagnetic field, humidity, vibration, and corrosion;
The nature of the measured medium: such as temperature, pressure level, viscosity, presence or absence of corrosion, pollution, flammable and explosive conditions, etc .;
The requirements for display, such as general on-site instructions, or the need for remote display signal alarm, data accumulation or automatic recording, etc .;
3. Determination of instrument measuring range
The upper and lower limits of the meter have been initially calculated, but this cannot be used as the measuring range of the meter; because the measuring range of the meter has been standardized and serialized by the national competent authority,
It cannot be selected arbitrarily, so you should consult the product manual and compare the measurement range series of the instrument with the final production according to the calculated value, and finally determine the corresponding upper and lower limits of the instrument measurement.
The measuring range of the meter should be determined according to the measured pressure. For elastic pressure gauges, in order to ensure that the elastic elements work reliably within the safe range of elastic deformation, determine the pressure
When measuring the range of the meter, you must pay attention to leaving enough room; generally, under the condition that the measured pressure is relatively stable, the maximum pressure value should not exceed 3/4 of the upper limit of the instrument measurement. Fluctuations in measured pressure
In larger cases, the maximum pressure value should not exceed 2/3 of the upper limit of the instrument. In order to ensure the measurement accuracy, the minimum value of the measured pressure should not be less than 1/3 of the measuring range of the instrument.
的选用应根据使用要求，针对具体情况做具体分析。 In short, the selection of the pressure gauge should be based on the use requirements and specific analysis for specific situations.