Advantages and disadvantages of membrane box pressure gauge and bellows pressure gauge

Advantages and disadvantages of membrane box pressure gauge and bellows pressure gauge
Advantages and disadvantages of capsule pressure gauge:
advantage:
Simple structure: The internal structure is relatively simple, mainly composed of a membrane box, transmission mechanism, indicator components, and housing, without overly complex mechanical structures. This makes its manufacturing and maintenance costs relatively low, and production and maintenance are relatively convenient.
High measurement accuracy: It has good accuracy for measuring small pressures and can accurately reflect changes in small pressures. It is suitable for situations that require high pressure measurement accuracy, such as experimental environments that require precise control of gas pressure and process flows that are sensitive to pressure changes.
Good stability: The elastic deformation of the membrane box is relatively stable, and it is less affected by external interference factors during the measurement process, which can maintain relatively stable measurement results and ensure the reliability of the measurement data.
Wide applicability: It can be used to measure the micro pressure and negative pressure of gases that do not corrode copper alloys and pose no explosion hazard. It is widely used in equipment such as boiler ventilation, gas pipelines, and combustion devices.
Obvious indication: The pointers on the dial indicate clearly and are easy to read, allowing operators to quickly and accurately read pressure values.
Disadvantages:
Limited measurement range: Typically, the measurement range of a bellows pressure gauge is between -80~60000Pa, which can only be used for measuring small and low pressures, and is not suitable for measuring high-pressure environments.
Temperature sensitivity: In environments with large temperature changes, the elastic properties of the membrane box may be affected to some extent, leading to an increase in measurement errors. Therefore, when used in high or low temperature environments, temperature compensation or other protective measures need to be taken for the bellows pressure gauge.
Advantages and disadvantages of bellows pressure gauge:
advantage:
High output thrust: The bellows will produce a large displacement when subjected to pressure, which can convert the pressure signal into a large thrust. Through the transmission mechanism, the pointer is driven to rotate, making the indication of the pressure gauge more obvious and accurate.
Suitable for low and medium pressure measurement: It has high sensitivity and measurement accuracy in the low and medium pressure range, and can accurately measure changes in low and medium pressures. It is particularly suitable for situations that require high low pressure measurement, such as urban gas pipelines, ventilation systems, etc.
Measurable corrosive media: can be used to directly measure the pressure of gases or liquids that do not crystallize and have a certain degree of corrosiveness, and has good adaptability to some corrosive working media.
Disadvantages:
Environmental temperature compensation is required: The material properties of the bellows are greatly affected by temperature, and temperature changes can cause changes in the elastic modulus of the bellows, thereby affecting the measurement accuracy of the pressure gauge. Therefore, environmental temperature compensation is required during use.
Cannot be used for high-pressure measurement: Due to the limited structural strength of the bellows, it cannot withstand excessive pressure, so its measurement range is limited and not suitable for pressure measurement in high-pressure environments.
Poor linearity: The linearity of pressure displacement is relatively poor, with a large hysteresis error, and usually the accuracy can only reach about 1.5 levels. To improve its linearity, it is usually necessary to install auxiliary devices such as coil springs inside the corrugated tube.