Method to reduce pressure transmitter measurement error
The pressure transmitter may cause the error during pressure transmission:
1. The difference in density due to the temperature difference between the pressure transmitters on both sides of the pressure transmitter (caused a head error).
4. Gas in the liquid line installed in the pressure transmitter (caused head error)
5. The pressure transmitter installed in the gas pipeline contains liquid (caused head error)
The method of reducing errors is as follows:
1. The pressure guiding tube should be as short as possible;
2. When the pressure transmitter is measuring liquid or steam, the pressure guiding pipe is connected upstream to the process pipeline, and its slope should not be less than 1/12;
3. When the pressure transmitter is used for gas measurement, the pressure guiding pipe is connected to the process pipe downwards, and its slope should not be less than 1/12;
4. The layout of the liquid pressure conduit shall be avoided to avoid the occurrence of high points in the middle, and the deployment of the gas guide tube shall avoid the occurrence of low points in the middle;
5. When using cleansing agent, the cleansing agent connection should be close to the process pipeline to take pressure. The pipeline passed by the cleansing agent should have the same length and caliber, and should avoid the cleansing agent passing through the pressure transmitter;
6. The same temperature should be maintained between the two pressure guiding tubes;
7. In order to avoid the influence of friction, the diameter of the pressure guiding tube should be large enough;
8. There should be no gas in the pressure-filled pipe filled with liquid;
9. When using spacer fluid, the two sides of the pressure tube should be the same liquid.