Manometers are devices (instruments) designed to measure the pressure of gas, liquid. Devices are classified into several types, depending on the characteristics. Before choosing pressure gauges, it is necessary to familiarize yourself with the features of their use.
Selection of instruments according to the range of measured pressure
- Pressure gauge. The device serves to measure the positive difference between the absolute pressure and the pressure of the barometer in the range from 0.06 to 1000 MPa.
- Tractor. Measures depression to 40 kPa.
- Vacuum meter. Serves for measuring pressure below ambient (atmospheric) up to 100 kPa.
- Headometer. Measures a slight overpressure (up to 40 kPa).
- Tractor gauge. The measurement limits correspond to the interval from - 20 to + 20 kPa.
- Manovacuum meter. This includes pressure gauges for measuring excess pressure (from 60 to 240000 kPa), as well as vacuum gauge (up to - 100 kPa).
- Differential pressure gauge. The device is designed to measure the pressure difference.
The most used are differential and absolute pressure instruments. Differential devices (pressure gauges) for measuring pressure show the difference of two values. Absolute pressure gauges show the value regardless of pressure fluctuations in the atmosphere.
Characteristics, manometer designs
Pressure gauges are divided into several types, depending on the design and structure of the devices: liquid, deadweight, deformation with a membrane, deformation with a tubular spring (with a Bourdon tube). The part makes it possible to measure pressure with a high degree of accuracy.
In medicine, membrane pressure gauges are used. They are the cleanest in environmental terms, in quality not worse than mercury.
Manometers for measuring gas pressure are very common. They consist of a housing in which the meters are located. Devices are installed in compressors, pumps, gas equipment. Gas manometers are accurate in readings.
Pressure gauges of any kind are classified by accuracy indicators. The smaller the number, the more accurate the display. Accuracy classes are as follows: 0.15; 0.25; 0.4; 0.6; 1.0; 1.5; 2.5; 4.0.
Scope of manometers
The manometers have many purposes. They are electric contact, general technical, reference, with a recorder, for special purposes.
- Contact manometers are used to control and measure pressure in liquid, gaseous, non-aggressive media.
- General technical pressure gauges are used to measure the pressure of steam, gas, liquid.
- Reference pressure gauges have a high accuracy rate. They check and calibrate other instruments. Basically, they are installed on deadweight devices.
- Pressure gauges with a recorder record the pressure reading on a special carrier mechanism.
- Special pressure gauges provide the necessary environmental conditions. These include: oxygen (blue), acetylene (white), hydrogen (gray-green) devices. Different colors are necessary to avoid negative consequences. For example, oxygen devices must be degreased, otherwise an explosion may occur if a contaminated device comes in contact with pure oxygen.
Pressure gauge for measuring fuel pressure can be used in various industries. When choosing a device, you should know that high-quality goods can only be purchased from a well-known manufacturer, with a worldwide reputation. The manufacturer must have a license for the right to release goods, a quality certificate. This is a very important fact. Indeed, measuring instruments are used in complex technological and industrial processes. And the safety of the progress of work and the quality of the final product depend on them.