Pressure gauges of 1.6 and 2.5 grades for industrial production. Precision pressure gauges or digital pressure gauges can be used for precision measurement requirements; pressure transmitters should be selected for remote transmission or control requirements. Proper selection of the measuring range of the pressure gauge can prolong the service life. For stable pressure measurement, the maximum range should be 1.5 times the measured value; for fluctuating pressure, the maximum range should be 2 times the measured value.
Common pressure gauges for air, water, steam, oil, etc., the case is black; special pressure gauges are required for certain media, such as ammonia pressure gauges for ammonia, the case is yellow; oxygen pressure gauges for oxygen, the case is sky blue ; The oxygen pressure gauge and acetylene pressure gauge should be strictly oil-proof. When the spring tube is contaminated with oil, carbon tetrachloride can be injected into the spring tube with a syringe, and it can be used after cleaning.
In addition to isolation, all stainless steel pressure gauges can be used for pressure measurement in highly corrosive media and corrosive gas environments, such as dilute hydrochloric acid and hydrochloric acid. However, all stainless steel pressure gauges are not suitable for corrosive media such as chlorine. , Nitric acid and other environments. Diaphragm pressure gauges can also be selected. There are a variety of materials for the isolation diaphragm, such as: 316, Monel, Hastelloy, tantalum and fluoroplastics, which can be selected according to the measurement medium.
Some isolation instruments use an indirect measurement structure. According to the nature of the measured medium, a meter or capillary is filled with a working fluid, such as glycerin or silicone oil, to transmit pressure. This type of instrument is suitable for measuring large viscosity, easy to crystallize, corrosive High temperature liquid, gas or medium pressure with solid floating matter. For occasions with large vibration, YN vibration-resistant pressure gauge or marine pressure gauge should be selected.
Where remote transmission, alarm and interlocking are required, a pressure transmitter should be selected to transmit the measured pressure to the display instrument or DCS card as a current signal. The pressure transmitter has a wide measuring range and is more flexible to use, with emphasis on pressure resistance and anti-corrosion issues.
The electric contact pressure gauge should be a magnetic-assisted electric contact device. Its action is stable and reliable, the contact power is large, and a damping device is set inside the instrument to resist medium pulsation or mechanical vibration. Explosion-proof electrical contact pressure gauges should be explosion-proof.
Capsule pressure gauges can be used for on-site micropressure measurement. Capsule pressure gauges are only suitable for measuring small pressures of gas or liquid media that are not corrosive to copper and copper alloys.
