Selection method and precautions of All STST pressure gauge
2022-09-13
The selection of All STST pressure gauge should be based on the specific situation and meet the technical requirements of the process. At the same time, the cost aspect should also be considered. We recommend that the following aspects should be considered when selecting instruments:
(1) The physical and chemical properties of the measured medium, such as temperature, viscosity, degree of contamination, corrosiveness, whether it is flammable, explosive, easy to crystallize, etc.
(2) Requirements for pressure measurement in the production process, such as the measured pressure range, degree and whether remote transmission, recording or upper and lower limit alarms are required.
(3) On-site environmental conditions, such as high temperature, corrosion, humidity, vibration, electromagnetic fields, etc.
Precautions:
1. The All STST pressure gauge must be placed vertically during prevention and control: it should be tightened with a wrench during installation, and do not directly screw the outer casing by hand, because this will damage the casing. Do not let it collide during transportation to avoid damage.
2. When using the pressure gauge, pay attention to control its amplitude below one millimeter.
3. During use, if the pointer of the meter cannot be lowered because the temperature in the environment is too high, the rubber plug on the case can be cut off to allow the atmosphere to enter the inside of the meter to easily solve this problem. .
4. When the instrument is in use, pay attention to the temperature of the outside world, and control the temperature of the outside environment at -25 to 55 degrees. Only within this temperature range can the pressure gauge work normally without damage.
5. The All STST pressure gauge should be inspected regularly during use. The inspection cycle is at least every three months. If any fault is found during the inspection, it should be repaired in time.
6. The use of All STST pressure gauges also has a certain range, and this range should be controlled within the range of one-third to two-thirds of the maximum value of the pressure gauge.
In order to ensure the accuracy of pressure measurement, the following points must be paid attention to when using the pressure gauge:
1.Selection of measuring points
The selected measurement point should be representative of the pressure being measured. The measurement point should be selected in the straight pipe section, far away from the local resistance. The pressure guiding tube should not extend into the measured object but should be flush with the process pipeline. The inner diameter of the pressure guiding tube is generally 6~10mm, and the length should not be greater than 50mm, otherwise it will cause transmission lag. In order to prevent the pressure guiding pipe from being blocked, the pressure taking point is generally selected on the horizontal pipe. When measuring liquid pressure, the pressure point should be at the lower part of the pipeline, so that no liquid accumulates in the pressure guiding pipe; if the liquid on the north side is easy to condense or freeze, pipeline insulation equipment must be installed.
2.Install
When measuring steam pressure, a condensing pipe or condenser should be installed to condense the steam measured in the pressure guiding pipe. When the measured fluid is corrosive or easy to crystallize, isolation fluid and isolator should be used to avoid damage to the measuring element of the pressure measuring instrument. The spacer liquid should be a liquid with high boiling point, low freezing point and stable physical and chemical properties. The pressure gauge should be installed as far as possible away from heat transfer and vibration to avoid its influence. A shut-off valve should be installed near the pressure-taking port for use in overhauling the pressure gauge.
3.Maintain
During use, the All STST pressure gauge should be cleaned regularly to keep the pressure guiding tube and pressure gauge clean.
(1) The physical and chemical properties of the measured medium, such as temperature, viscosity, degree of contamination, corrosiveness, whether it is flammable, explosive, easy to crystallize, etc.
(2) Requirements for pressure measurement in the production process, such as the measured pressure range, degree and whether remote transmission, recording or upper and lower limit alarms are required.
(3) On-site environmental conditions, such as high temperature, corrosion, humidity, vibration, electromagnetic fields, etc.
In addition, for elastic pressure gauges, in order to ensure that the elastic elements work reliably within the safe range of elastic deformation, prevent pressure damage to the elastic elements, and affect the service life of the instrument, the range selection of the pressure gauge must leave enough room. Generally, when the measured pressure is relatively stable, the maximum working pressure should not exceed 3/4 of the full scale of the instrument, and when the measured pressure fluctuates greatly, the maximum working pressure should not exceed 2/3 of the full scale of the instrument. In order to ensure the measurement accuracy, the minimum value of the measured pressure should not be lower than 1/3 of the full scale.
Precautions:
1. The All STST pressure gauge must be placed vertically during prevention and control: it should be tightened with a wrench during installation, and do not directly screw the outer casing by hand, because this will damage the casing. Do not let it collide during transportation to avoid damage.
2. When using the pressure gauge, pay attention to control its amplitude below one millimeter.
3. During use, if the pointer of the meter cannot be lowered because the temperature in the environment is too high, the rubber plug on the case can be cut off to allow the atmosphere to enter the inside of the meter to easily solve this problem. .
4. When the instrument is in use, pay attention to the temperature of the outside world, and control the temperature of the outside environment at -25 to 55 degrees. Only within this temperature range can the pressure gauge work normally without damage.
5. The All STST pressure gauge should be inspected regularly during use. The inspection cycle is at least every three months. If any fault is found during the inspection, it should be repaired in time.
6. The use of All STST pressure gauges also has a certain range, and this range should be controlled within the range of one-third to two-thirds of the maximum value of the pressure gauge.
In order to ensure the accuracy of pressure measurement, the following points must be paid attention to when using the pressure gauge:
1.Selection of measuring points
The selected measurement point should be representative of the pressure being measured. The measurement point should be selected in the straight pipe section, far away from the local resistance. The pressure guiding tube should not extend into the measured object but should be flush with the process pipeline. The inner diameter of the pressure guiding tube is generally 6~10mm, and the length should not be greater than 50mm, otherwise it will cause transmission lag. In order to prevent the pressure guiding pipe from being blocked, the pressure taking point is generally selected on the horizontal pipe. When measuring liquid pressure, the pressure point should be at the lower part of the pipeline, so that no liquid accumulates in the pressure guiding pipe; if the liquid on the north side is easy to condense or freeze, pipeline insulation equipment must be installed.
2.Install
When measuring steam pressure, a condensing pipe or condenser should be installed to condense the steam measured in the pressure guiding pipe. When the measured fluid is corrosive or easy to crystallize, isolation fluid and isolator should be used to avoid damage to the measuring element of the pressure measuring instrument. The spacer liquid should be a liquid with high boiling point, low freezing point and stable physical and chemical properties. The pressure gauge should be installed as far as possible away from heat transfer and vibration to avoid its influence. A shut-off valve should be installed near the pressure-taking port for use in overhauling the pressure gauge.
3.Maintain
During use, the All STST pressure gauge should be cleaned regularly to keep the pressure guiding tube and pressure gauge clean.
