Online calibration method for oil pipeline pressure transmitter Abstract: This paper aims to explore a new online calibration technology for oil pipelines with root valves. It is proposed that the venting method can effectively overcome the shortcomings of current traditional metrology techniques in terms of efficiency and safety through divergent thinking. The reverse compression method extended by this online pressure calibration method is proposed to be more widely used. As an important monitoring and control instrument for oil pipelines, pressure transmitters play a vital role in the normal operation of the entire pipeline. The pressure transmitter is mainly composed of a load cell sensor (also called a pressure sensor), a measuring circuit and a process connection. It can convert the physical pressure parameters such as gas and liquid felt by the load cell sensor into standard electrical signals (such as 4~20 mADC, etc.) to supply the secondary instrument such as indicating alarm device, recorder, regulator, etc. Instructions and process adjustments. It can monitor the pressure data collected in the field, display it synchronously to the monitoring host of the station control room, and can alarm the abnormal pressure value, and feed back the abnormal situation to the station staff for the first time to avoid the deterioration of the abnormal situation. At the same time, it can also switch the control of the corresponding pipeline valve according to the collected pressure through the designed control program to avoid causing major safety accidents. Therefore, the accuracy of the pressure value of the pressure transmitter must be ensured by traceability, otherwise it will easily cause false alarms and misoperations, resulting in unnecessary losses. I have been involved in the West-East Gas Transmission, Sichuan-East Gas Transmission, and local gas company's pressure meter calibration work for many years. Now I have shared some methods for online calibration of pressure transmitters for petroleum gas pipelines in recent years. The pressure monitoring of the oil gas pipeline is mainly through the bypass on the main pipeline. The root valve and the vent valve and the venting pipe are generally installed on the bypass, and then the pressure transmitter is connected to the monitoring host for pressure. Monitoring and control [2]. The root valve, vent valve and vent tube are mainly installed to facilitate maintenance and replacement of the pressure in the future. During normal operation, the root valve is open and the vent valve is closed. The main pipe pressure can be smoothly passed through the bypass to the pressure transmitter, through data transmission to the monitoring host, and when we send pressure to the pressure When the maintenance and replacement work needs to be relieved, the root valve can be closed, the pressure connection between the main pipe and the bypass can be cut off, and the vent valve can be opened to release the residual pressure of the bypass through the vent pipe to complete the pressure relief work. Usually the calibration of the pressure transmitter is carried out by removing the pressure transmitter from the pipe and then connecting it to the standard meter used in our metering for pressure calibration. In the disassembly process, the pressure transmitter, pressure and bypass interface need to be disassembled, and the power supply line of the pressure transmitter needs to be removed. The power supply line is deeply buried in the insulation protection sleeve, and the entire pressure transmitter needs to be removed. When two people work together, the disassembly takes nearly 15 minutes, and the multiple disassembly and installation of the interface are easily damaged, resulting in a tight seal, resulting in air leakage and accidents. Although the conventional detection method can meet the requirements of metering and traceability, the disadvantage is that the efficiency of the metering work is too slow, the disassembly and assembly time is relatively long, and the frequent disassembly and assembly is very likely to cause damage to the connector. Thinking about the measurement experience of the pressure transmitter and its working principle, we adopted the pressure method of connecting from the venting pipeline to completely solve the problem of online detection of the pressure transmitter. The specific method for venting the venting line is to first close the root valve, block the bypass from the main pressure, and then open the vent valve to exhaust the residual pressure of the bypass, then remove the venting tube and bring the high voltage The hose is threaded into the bypass venting area to complete the connection of the standard to the pressure transmitter. Application of Reverse Pressure Method of Ventilation Tube Unicom Pressurization Method in General Pressure Instrument In this new online inspection method, we only need to remove the venting pipe, the disassembly parts are small, and only need to disassemble the venting pipe thread, one person can complete the disassembly work within 1 min, and it is a non-important part, it will not It has an impact on the main connection parts and is safe and efficient. At the same time, when we pressurize, we can fine-tune the root valve, use the pressure gas in the pipeline as the pressure source, and save the physical strength of the pressure transmitter calibration work. It can be seen that the new venting tube communication method has high detection efficiency, strong safety reliability and operability, which can save time and effort. Pressure instrumentation with a structure such as a root valve venting valve on an oil gas pipeline has a wide versatility. With this method as the point of convergence and inspiration, we also think of the versatility of this method in the calibration of general pressure instruments through divergent thinking. Can this reverse pressure detection method be applied to a wider range of pressure instruments? In the calibration. This provides a new idea for online metering and calibration of our pressure instruments. It is not difficult to know the principle of this method. For pressure instruments with separate control of intake and exhaust valves, if the intake end is not easy or not Allow connection, we can use this reverse pressure to carry out on-line inspection and calibration. For the pressurized source, we can select the air pump on the standard meter to pressurize or pressurize the pressure control system of the instrument. online test.

Online calibration method for oil pipeline pressure transmitter

Abstract: This paper aims to explore a new online calibration technology for oil pipelines with root valves. It is proposed that the venting method can effectively overcome the shortcomings of current traditional metrology techniques in terms of efficiency and safety through divergent thinking. The reverse compression method extended by this online pressure calibration method is proposed to be more widely used.

         As an important monitoring and control instrument for oil pipelines, pressure transmitters play a vital role in the normal operation of the entire pipeline. The pressure transmitter is mainly composed of a load cell sensor (also called a pressure sensor), a measuring circuit and a process connection. It can convert the physical pressure parameters such as gas and liquid felt by the load cell sensor into standard electrical signals (such as 4~20 mADC, etc.) to supply the secondary instrument such as indicating alarm device, recorder, regulator, etc. Instructions and process adjustments. It can monitor the pressure data collected in the field, display it synchronously to the monitoring host of the station control room, and can alarm the abnormal pressure value, and feed back the abnormal situation to the station staff for the first time to avoid the deterioration of the abnormal situation. At the same time, it can also switch the control of the corresponding pipeline valve according to the collected pressure through the designed control program to avoid causing major safety accidents. Therefore, the accuracy of the pressure value of the pressure transmitter must be ensured by traceability, otherwise it will easily cause false alarms and misoperations, resulting in unnecessary losses. I have been involved in the West-East Gas Transmission, Sichuan-East Gas Transmission, and local gas company's pressure meter calibration work for many years. Now I have shared some methods for online calibration of pressure transmitters for petroleum gas pipelines in recent years.

         The pressure monitoring of the oil gas pipeline is mainly through the bypass on the main pipeline. The root valve and the vent valve and the venting pipe are generally installed on the bypass, and then the pressure transmitter is connected to the monitoring host for pressure. Monitoring and control [2]. The root valve, vent valve and vent tube are mainly installed to facilitate maintenance and replacement of the pressure in the future. During normal operation, the root valve is open and the vent valve is closed. The main pipe pressure can be smoothly passed through the bypass to the pressure transmitter, through data transmission to the monitoring host, and when we send pressure to the pressure When the maintenance and replacement work needs to be relieved, the root valve can be closed, the pressure connection between the main pipe and the bypass can be cut off, and the vent valve can be opened to release the residual pressure of the bypass through the vent pipe to complete the pressure relief work.

         Usually the calibration of the pressure transmitter is carried out by removing the pressure transmitter from the pipe and then connecting it to the standard meter used in our metering for pressure calibration. In the disassembly process, the pressure transmitter, pressure and bypass interface need to be disassembled, and the power supply line of the pressure transmitter needs to be removed. The power supply line is deeply buried in the insulation protection sleeve, and the entire pressure transmitter needs to be removed. When two people work together, the disassembly takes nearly 15 minutes, and the multiple disassembly and installation of the interface are easily damaged, resulting in a tight seal, resulting in air leakage and accidents. Although the conventional detection method can meet the requirements of metering and traceability, the disadvantage is that the efficiency of the metering work is too slow, the disassembly and assembly time is relatively long, and the frequent disassembly and assembly is very likely to cause damage to the connector. Thinking about the measurement experience of the pressure transmitter and its working principle, we adopted the pressure method of connecting from the venting pipeline to completely solve the problem of online detection of the pressure transmitter. The specific method for venting the venting line is to first close the root valve, block the bypass from the main pressure, and then open the vent valve to exhaust the residual pressure of the bypass, then remove the venting tube and bring the high voltage The hose is threaded into the bypass venting area to complete the connection of the standard to the pressure transmitter.

Application of Reverse Pressure Method of Ventilation Tube Unicom Pressurization Method in General Pressure Instrument

         In this new online inspection method, we only need to remove the venting pipe, the disassembly parts are small, and only need to disassemble the venting pipe thread, one person can complete the disassembly work within 1 min, and it is a non-important part, it will not It has an impact on the main connection parts and is safe and efficient. At the same time, when we pressurize, we can fine-tune the root valve, use the pressure gas in the pipeline as the pressure source, and save the physical strength of the pressure transmitter calibration work.
         It can be seen that the new venting tube communication method has high detection efficiency, strong safety reliability and operability, which can save time and effort. Pressure instrumentation with a structure such as a root valve venting valve on an oil gas pipeline has a wide versatility. With this method as the point of convergence and inspiration, we also think of the versatility of this method in the calibration of general pressure instruments through divergent thinking. Can this reverse pressure detection method be applied to a wider range of pressure instruments? In the calibration. This provides a new idea for online metering and calibration of our pressure instruments. It is not difficult to know the principle of this method. For pressure instruments with separate control of intake and exhaust valves, if the intake end is not easy or not Allow connection, we can use this reverse pressure to carry out on-line inspection and calibration. For the pressurized source, we can select the air pump on the standard meter to pressurize or pressurize the pressure control system of the instrument online test.

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