Do you want to gain a deeper understanding of instrumentation knowledge? To communicate, select, use, and conduct metrological verification more effectively in your work, it is particularly important to classify pressure gauges appropriately. This article will reveal ten classification methods for pressure gauges to you. These methods are not absolute and aim to provide you with a more comprehensive perspective.

1. Classify according to the category of measured pressure

* Pressure gauge: used for measuring positive pressure. * Vacuum gauge: specifically designed for measuring vacuum levels. * Pressure-vacuum gauge: combines the functions of measuring both pressure and vacuum levels. * Differential pressure gauge: used for measuring the difference between two pressure points. * Absolute pressure gauge: measures absolute pressure, which is pressure measured from absolute zero.

2. Classification by measurement range

* **-40000~40000Pa**: suitable for high and low pressure measurements in special occasions. * **0~0.06MPa to 0~1000MPa**: covers various common pressure ranges to meet different application needs.

3. Comprehensive classification based on measured pressure and measurement range

* **-0.1~0MPa**: used for measuring minor pressure changes. * **-0.1~0.06MPa to -0.1~2.4MPa**: provides multiple subdivision ranges to meet precise measurement needs.

General pressure gauge

This type of pressure gauge is suitable for most conventional pressure measurement scenarios. With its wide measurement range, easy operation, and high cost-effectiveness, it is the most widely used pressure gauge in the industrial field.

Pressure vacuum gauge range and accuracy

The measuring ranges of the pressure vacuum gauge include 0.16, 0.25, 0.4, 0.6, 1.0, 1.6, and 2.5 (MPa). These measuring ranges are consistent with the upper measurement limit of the pressure gauge, ensuring consistency in accuracy level and maximum permissible error.

Precision Pressure Gauge

A precision pressure gauge is a high-precision measuring instrument with a wide range of measurement capabilities, covering various application scenarios. It plays a crucial role in industrial production, scientific research and experimentation, as well as quality control. Through its precise measurements, people can timely grasp the pressure changes in the system and make corresponding adjustments and decisions.

3. Accuracy level classification of precision pressure gauges

The accuracy level of a precision pressure gauge is a key indicator for measuring its measurement accuracy. These levels include 0.06, 0.1, 0.16, 0.25, 0.4, and 0.6, totaling six levels. It is worth noting that in JJG 49-1999 "Verification Regulation for Spring Tube Precision Pressure Gauges and Vacuum Gauges", the 0.06 level is mainly used as a reference level for technological development, while the 0.6 level is a downgraded use level of the 0.4 level.

4. Classification of nominal diameters of pressure gauge casings

The nominal diameter of the housing of a precision pressure gauge is an important parameter of its physical dimensions, directly affecting its range of use and convenience. These diameters include various specifications such as Φ40mm, Φ50mm, Φ60mm, Φ100mm, Φ150mm, Φ200mm, Φ250mm, Φ300mm, and Φ400mm to meet different measurement needs.

② Correlation between the nominal diameter of the precision pressure gauge housing and its accuracy level

There exists a certain relationship between the nominal diameter of the housing and the accuracy level of a precision pressure gauge. Generally speaking, pressure gauges with larger diameters tend to have relatively higher accuracy levels. This is because large-diameter pressure gauges typically have a wider measurement range and finer scales, thus providing more accurate measurement results. However, this does not mean that small-diameter pressure gauges cannot meet high-precision measurement requirements. The selection of a suitable pressure gauge also requires comprehensive consideration of other factors, such as measurement range and usage environment.

5. Classification of precision pressure gauges

Precision pressure gauges can be classified in various ways based on different criteria. Firstly, according to the elastic elements used, they can be divided into types such as spring-loaded, diaphragm, capsule, and bellows. Secondly, based on the working medium used, they can be classified into oil medium, gas medium, filling fluid, and corrosion-resistant, high-viscosity, easily crystallizable, and easily solidifying media. In addition, there are classifications based on usage, such as for standard instruments, indicating pressure, specific gases, shock resistance, stainless steel, etc. Meanwhile, according to the measured pressure level, they can be divided into vacuum gauges, micropressure gauges, low pressure gauges, medium pressure gauges, high pressure gauges, and ultra-high pressure gauges. Furthermore, based on the indication method of the display, they can be classified into pointer type, recording type, and digital display type. Finally, according to the threaded connection and installation method, pressure gauges can be divided into direct installation, flush mounting (disc mounting), and protruding mounting (wall mounting) types.

The installation methods of precision pressure gauges can be divided into radial direct mounting and flush mounting.