Radial/axial 360° along-way wellbore wax deposition evaluation method and imaging method

Abstract

The present invention discloses a device for measuring and imaging the wax precipitation amount of a radial / axial 360-degree along-the-way wellbore. The device comprises an ultrasonic detector measurement unit and a measurement data imaging and processing unit. The ultrasonic detector measurement unit comprises a rotary motor, a lifting motor, a rotating mechanism, a rotating test rod, a displacement sensor and an ultrasonic detector. The measurement data imaging and processing unit comprises a measuring data processing system and a 360-degree imaging and processing system. An evaluation method of the device comprises the following steps of measuring the emission time of the ultrasonic detector; measuring the reflection-wave reception time of the ultrasonic detector; and calculating the wax precipitation thickness value of a test pipe section in a cylindrical coordinate system. An imaging method of the device comprises the following steps of converting the wax precipitation thickness value of the test pipe section from the cylindrical coordinate system into a rectangular coordinate system; subjecting the wax precipitation thickness value to normalized treatment; generating a colorful wax precipitation thickness effect picture in a two-dimensional rectangular coordinate system; and converting the above effect picture into a 360-degree and rotatable colorful cylindrical three-dimensional wax precipitation thickness imaging picture. According to the technical scheme of the invention, the distribution of the radial and axial wax precipitation thickness and the distribution of the along-the-way wax precipitation cross-section curve of an along-the-way wellbore in the test pipe section can be realized.

Description

technical field [0001] The present invention relates to the measurement and evaluation of wellbore wax deposition, in particular to a wax deposition evaluation method based on a radial / axial 360-degree along-way wellbore wax deposition measurement imaging device and a radial / axial radial / axial method of wellbore wax deposition 360° imaging method. Background technique [0002] During the development of offshore heavy oil / high pour point oil reservoirs, wax deposition in the wellbore is common. Waxing in the wellbore will directly lead to a decrease in the effective flow area in the wellbore, an increase in fluid friction along the way, a decrease in single well productivity, and an increase in the frequency of workover operations. Severe wax deposition will block the wellbore and lead to the shutdown of the development well, seriously affecting the development effect of the production well. The problem of wax deposition is an important factor for the safe, stable and econo...

AI Technical Summary

Problems solved by technology

①The direct method is to "take out" the deposited wax in the target pipe section and weigh it to determine the thickness of the wax deposition. This method is straightforward and simple, and can be used for visual inspection and wax composition analysis, but this method is time-consuming and poor in operability

②Pressure drop measurement method is based on relevant hydraulic theories and assumes that the wax deposition thickness is uniform. By measuring the difference in pressure drop between the test section and the reference section, the average wax deposition thickness is calculated. The calculation results are consistent with the actual wellbore wax deposition. There is a certain deviation, and the calculation accuracy is not high

However, the operation process of this method is complicated, and there are too many influencing factors in the test process, so it is difficult to control the accuracy of the results.

The physical quantities measured by the above methods are the average value of the wax deposition thickness of the target pipe section, and the distribution of the radial and axial wax deposition thickness along the wellbore in the test pipe section cannot be obtained

This method is applied to single-phase pipe flow wax deposition with high measurement accuracy, but it cannot provide accurate wax deposition data for high-pressure single-phase flow and multi-phase flow

In recent years, a new test method has also been developed. One is to use ultrasonic positioning technology to realize online measurement in the case of uneven distribution of wax deposit thickness, but the degree of automation of the test, the data processing method and imaging display after the test are still in their infancy. stage, the method upper part matures

The other is to use the hole surface inspection instrument to take pictures of the wax deposits in the disassembled test pipe section, and can measure the local wax deposit thickness, but the accuracy of this method mainly depends on the characteristics of the deposits, such as hardness and oil content, this method has a narrow scope of application and is not suitable for popularization

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