膜盒壓力表和波紋管壓力表的優(yōu)缺點

膜盒壓力表的優(yōu)缺點：

優(yōu)點：

結(jié)構(gòu)簡單：內(nèi)部結(jié)構(gòu)相對不復(fù)雜，主要由膜盒、傳動機構(gòu)、指示部件和外殼等組成，沒有過于復(fù)雜的機械結(jié)構(gòu)，這使得其制造和維護成本相對較低，生產(chǎn)和維修都比較方便。

測量精度較高：對于微小壓力的測量具有較好的精度，能夠準確地反映出較小壓力的變化，適用于對壓力測量精度要求較高的場合，比如一些需要精確控制氣體壓力的實驗環(huán)境、對壓力變化敏感的工藝流程等。

穩(wěn)定性好：膜盒的彈性形變相對較為穩(wěn)定，在測量過程中受外界干擾因素的影響較小，能夠保持較為穩(wěn)定的測量結(jié)果，確保了測量數(shù)據(jù)的可靠性。

適用范圍廣：可用于測量對銅合金不起腐蝕作用、無爆炸危險的氣體的微壓和負壓，廣泛應(yīng)用于鍋爐通風(fēng)、氣體管道、燃燒裝置等設(shè)備上。

指示明顯：表盤上的指針指示清晰，讀數(shù)方便，操作人員可以快速準確地讀取壓力數(shù)值。

缺點：

測量范圍有限：通常膜盒壓力表的測量范圍在 - 80~60000Pa 之間，只能適用于測量微小壓力和較低壓力的場合，對于高壓環(huán)境的測量則不適用。

對溫度敏感：在溫度變化較大的環(huán)境中，膜盒的彈性特性可能會受到一定的影響，從而導(dǎo)致測量誤差的增大。因此，在高溫或低溫環(huán)境下使用時，需要對膜盒壓力表進行溫度補償或采取其他防護措施。

波紋管壓力表的優(yōu)缺點：

優(yōu)點：

輸出推力大：波紋管在受到壓力作用時會產(chǎn)生較大的位移，能夠?qū)毫π盘栟D(zhuǎn)化為較大的推力，通過傳動機構(gòu)驅(qū)動指針轉(zhuǎn)動，使得壓力表的指示更加明顯、準確。

適用于低、中壓測量：在低、中壓范圍內(nèi)具有較高的靈敏度和測量精度，能夠準確地測量出較低壓力和中等壓力的變化，特別適用于一些對低壓測量要求較高的場合，如城市燃氣管道、通風(fēng)系統(tǒng)等。

可測量腐蝕性介質(zhì)：可以用來直接測量不會結(jié)晶且具有一定腐蝕性的氣體或液體的壓力，對于一些具有腐蝕性的工作介質(zhì)具有較好的適應(yīng)性。

缺點：

需要環(huán)境溫度補償：波紋管的材料特性受溫度影響較大，溫度變化會導(dǎo)致波紋管的彈性模量發(fā)生變化，從而影響壓力表的測量精度，因此在使用過程中需要進行環(huán)境溫度補償。

不能用于高壓測量：由于波紋管的結(jié)構(gòu)強度有限，無法承受過高的壓力，所以其測量范圍受到限制，不適用于高壓環(huán)境的壓力測量。

線性度較差：壓力位移線性度相對較差，遲滯誤差較大，通常精度只能達到 1.5 級左右。為了提高其線性度，通常需要在波紋管內(nèi)部安裝螺旋彈簧等輔助裝置。

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.