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Stainless Steel Pressure Gauge The Main Basis Of Selection
- Jun 02, 2017 -

The correct selection of the pressure meter mainly includes determining the type, range, scope, accuracy and sensitivity of the instrument, Stainless Steel Pressure Gauge the shape and size, and whether the need for remote transmission and other functions, such as instructions, records, regulation, alarm and so on.

The main basis of the pressure instrument selection:

1. The requirements for measurement in process production process, including range and accuracy. In the case of static test (or slow change), Stainless Steel Pressure Gauge the maximum value of the pressure gauge is chosen to be two-thirds of the full scale of the pressure, and the maximum value of the measured pressure in the case of fluctuating pressure is selected by One-second of the scale value of the pressure gauge.

The accuracy level of common pressure measuring instruments is 0.05, 0.1, 0.25, 0. 4, 1, 1.5 and 2.5 grade 6, from the production process accuracy requirements and the most economical angle. The maximum allowable error of the instrument is the product of the scale of the pressure gauge and the degree of accuracy, and if the error value exceeds the accuracy of the process requirement, Stainless Steel Pressure Gauge the pressure meter with a high accuracy of a is needed.

2. The properties of the measured medium, such as state (gas, liquid), temperature, viscosity, corrosivity, degree of contamination, flammable and explosive degree, etc. such as oxygen table, acetylene table, with "Forbidden oil" sign, specially used for special medium corrosion-resistant pressure gauges, high temperature pressure gauges, diaphragm pressure gauges.

3. On-site environmental conditions, such as ambient temperature, corrosion, vibration, moisture and so on. such as shockproof pressure gauges used for vibration environmental conditions.

4. Suitable for staff observation. According to the position and illumination of the instrument, the meter with different diameter (dimensions) is selected.

For pressure testing, a measurement system is actually needed. In order to accurately measure, in addition to the instrument for the correct selection and verification (calibration), you must also pay attention to the correct installation of the entire system. If only the seismic pressure gauge itself is accurate, Stainless Steel Pressure Gauge its indication does not completely represent the actual parameters of the measured medium, because the error of the measurement system is not equal to the instrument error.

The correct installation of the system includes the opening position of the pressure opening, the reasonable laying of the connecting catheter and the correct installation position of the instrument.

1. The position selection of the pressure port (1) avoids the area in which the pipe bends, forks and streams are formed by Eddy Current. (2) When there are prominent objects (such as temperature measuring elements) in the pipeline, the pressure inlet should be taken in front of it. (3) When the pressure must be in the vicinity of the regulating valve, if the pressure mouth at the front, then the valve distance should not be less than twice times the diameter of the pipe; (4) For a wide container, Stainless Steel Pressure Gauge the pressure inlet should be in a smooth flow and no eddy current area. In a word, the location of the pressure nozzle determined in the process flow should be able to ensure the selected process parameters.

2. Laying of connecting ducts

The horizontal section of the connecting catheter should have a certain inclination to facilitate the removal of condensed liquids or gases.

When the measured medium is a gas, the catheter should be inclined toward the pressure inlet, and when the medium is measured, the catheter should tilt to the direction of the measuring instrument, and the tilt may be slightly larger when the measured parameter is a smaller differential pressure. Stainless Steel Pressure Gauge In addition, if the catheter is in the upper and lower corners, the discharge condensation liquid device or the discharge device shall be placed at the lowest point in accordance with the medium of the catheter to ensure that the accuracy of the measurement is not affected by the accumulation of condensation liquids or gases in the catheter for a considerable period of time. The condensed liquid or gas should be discharged periodically.