In order to better develop and improve the utilization rate of enterprise resources, it is necessary for professional staff to carry out flow measurements for enterprises. Therefore, in order to ensure the efficiency of flow measurement and the accuracy of measurement results, it is necessary to pay more attention to the flowmeter, reduce the error of measurement results by using on-site calibration technology, and select appropriate flow measuring instruments and measurement methods according to the specific content of the measurement, so as to further improve the flow measurement level and highlight the value of measuring instruments and on-site calibration technology, Provide favorable conditions for the development and utilization of enterprise resources.
Analysis of advantages of on-site calibration technology
When measuring the flow, the on-site calibration technology has the following advantages.
(1) The actual application object on site is the calibrated medium. In this case, the use of flow meters for relevant measurement can greatly reduce the error of measurement results and improve the accuracy and authenticity of the overall measurement.(2) The application of field calibration technology in enterprise measurement work can effectively simplify and improve the workflow of instrument inspection, so as to better reduce the workload of personnel.
(3) In the past, the inspection instrument needs to involve transportation and other related work steps before and after verification. In this process, it is easy to cause instrument measurement deviation due to human operation, and the use of on-site calibration technology can avoid the occurrence of such human factors.
(4) The measurement work of enterprises has a strong continuity. In this working state, it is difficult for some instruments to conduct offline periodic verification, and the use of this technology can be effectively improved and processed.
(5) In the application process of field calibration technology, while optimizing the instrument verification process, it can reduce the verification cost and effectively shorten the instrument verification cycle time.
Field calibration technology of pressure transmitter
First of all, according to the actual situation and relevant needs of the enterprise, the staff needs to select the pressure calibrators that meet the conditions such as model and specification and use them as the on-site calibration instruments of the enterprise. Secondly, in order to complete the field calibration of the pressure transmitter, the staff are required to calibrate the measuring instrument in use in the corresponding places, such as the water injection station and the calibration room. After verification, the measurement error of the instrument shall be calculated and judged according to the parameters and conditions obtained from verification. The parameters verified mainly involve zero point, full range, etc. The conditions required for calculation and judgment also include the model, number, range, accuracy, output current, and other parameters of the pressure transmitter. For the verification of the pressure transmitter, selecting the correct and appropriate pressure calibrator can accurately verify the parameters and conditions of the pressure transmitter, so as to effectively determine whether the measurement accuracy meets the standard range. At the same time, the operation of the pressure calibrator itself is relatively simple, convenient, safe, and stable, which can play an important role in solving the problem of online verification.
Field calibration technology application of flow metering instrument
Applied to sewage flow measurement
There are two main methods for on-site calibration technology of enterprise sewage flow measurement.
(1) The 5000m3 water injection tank of each water injection station is used to calibrate the flow measuring instrument used for sewage online. First, determine the online calibration process, generally the specific production process of the water injection station, and use the 5000m3 water injection tank as the standard volume tank. Before calibrating the measuring instruments, the staff needs to inject the treated sewage into the water injection tank. After the sewage is filled, the water inlet valve should be closed, and other relevant equipment and instruments should stop production. Only the flow-measuring instruments that need to be calibrated should be kept for continuous operation. When all conditions of the water injection system are stable, the staff can formally carry out the calibration work. In order to ensure that each verification point of the flow metering instrument can be verified successfully, the opening of the outlet valve of the high-pressure water injection pump can be adjusted according to the operation requirements. At the same time, the reduction of the 5000m3 water injection tank is the true value, and the accumulated amount of flow metering instrument is the measured value. Through calculation and comparison, the measurement error value of each verification point of the metering instrument can be obtained.
(2) Select the correct ultrasonic flowmeter to complete the field calibration of flow measuring instruments. The ultrasonic flowmeter is convenient and intuitive, and the overall measurement speed is fast. However, the flowmeter also has corresponding disadvantages, such as high pricing, single measuring medium, and low measurement accuracy. Therefore, in the specific application process, the staff should also reasonably choose the calibration method according to the actual situation of the enterprise.
Application to crude oil flow metering
For the field calibration of crude oil flow measurement, the staff can choose the volumetric Roots flowmeter for the corresponding calibration. This flowmeter has many years of practical application experience and has been calibrated on a large-diameter site. The staff needs to adopt the standard meter method to install and set the marker device and determine the parameters of the relevant flowmeter. If the accuracy of the crude oil flow metering instrument for flow verification is required, it should be level 0.5, and the standard meter of Roots flowmeter should be level 0.2. When installing the marker device, the staff needs to provide two sets. The online verification work of the first set of devices is mainly aimed at the ore metering flowmeter to effectively improve and ensure the accuracy of crude oil flow measurement. The regular verification work carried out for the second set of devices is mainly for the export metering of oil production plants. The reasonable operation of the two sets of devices can improve the automation level of crude oil flow measurement and verification, and reduce the workload of staff while ensuring verification efficiency.Applied to natural gas flow metering
There is a large amount of natural gas stored in the oil field. In order to make better use of natural gas, the staff should be able to accurately understand the natural gas flow and effectively carry out the natural gas measurement. At present, the devices equipped by most enterprises for natural gas flow measurement mainly include bell jar gas meter standard devices and sonic nozzle gas meter standard devices. However, the existing devices have certain requirements for the flowmeter diameter during construction. Generally, the natural gas flowmeter with a diameter of more than 100mm cannot be measured with this device. In order to ensure the accuracy of large-diameter flow meters, the staff should send them for verification. Large-diameter flowmeters are generally used in various gas distribution stations. In this case, according to the situation of each gas distribution station and the actual diameter of the natural gas flowmeter, an online standard device for a large caliber sonic nozzle can be established for the on-site calibration of metering instruments. This can not only effectively reduce the cost of external verification, but also further improve the accuracy of flow meters.
Applied to water content analyzer and temperature transmitter
In addition to the on-site calibration of enterprise sewage flow measurement and natural gas flow measurement, the technology can also be used for water content analyzers and temperature transmitters. Water content analyzer: the staff shall select the appropriate on-site calibration method according to the specific situation. For the low water content analyzer, the staff can select a distillation method to calibrate its relevant parameters and conditions. For the high water content analyzer, the staff can choose to calibrate the relevant parameters and conditions by taking off the electricity. Temperature transmitters: At present, the total number of temperature transmitters in enterprises is not very large. In this case, staff can carry out indoor calibration. If the subsequent relevant conditions are met, the staff can select appropriate calibration instruments such as specifications and models for on-site calibration.
Suggestions for Improving the Application Effect of Field Calibration Technology for Flow Meters
For the field calibration of flow metering instruments, in order to better improve the application effect of field calibration technology and ensure the accuracy of flow metering, the following work should be strengthened:(1) There are many processes and contents involved in the on-site calibration. All departments and personnel of the enterprise should strengthen communication and cooperation to improve the overall coordination and cooperation ability. Only in this way can the on-site calibration work be carried out orderly.
(2) For the on-site calibration of sewage flow measurement of the water injection tank, the pump should be started and stopped many times during the calibration process, which is easy to affect the overall operation stability of the water injection system. In the calibration process, due to the relatively large flow, manual detection is prone to error. Therefore, the staff needs to strictly control the number of pump startups and shutdown and operations and select the automatic detection method of the liquid level transmitter to further reduce the measurement error.
(3) Different types of flow measurement correspond to different field calibration methods and also require different equipment and meters. The staff should pay more attention to the selection of instruments and equipment with correct specifications and models and appropriate calibration methods in strict accordance with the requirements and actual conditions.
(4) The enterprise shall carry out technical training for personnel involved in on-site calibration to ensure that they can master various on-site calibration methods and can skillfully apply the on-site calibration technology to ensure the accuracy of flow measurement.(5) In future development, in order to improve the production level of the enterprise and enhance the utilization effect of enterprise resources, it is also necessary to strengthen the research and application of technology, so as to further improve the effectiveness of on-site calibration technology and ensure the accuracy of measurement data.
