CN-121993172-A - Method, system, equipment and medium for calculating bottom hole flow pressure of oil well

CN121993172ACN 121993172 ACN121993172 ACN 121993172ACN-121993172-A

Abstract

The invention provides a method, a system, equipment and a medium for calculating the bottom hole flow pressure of an oil well, which comprises the following steps that the oil well with high gas-liquid ratio is divided into a mixed liquid section, a foam pure oil section and a pure gas section from bottom to top; the method comprises the steps of respectively calculating the pressure of a foam pure oil section and the pressure of a pure gas section, calculating the pressure of a mixed liquid section according to the obtained pressure of the foam pure oil section and the pressure of the pure gas section by combining a segmentation method, calculating the bottom hole flow pressure of a target oil well according to the obtained pressure of the pure gas section, the pressure of the foam pure oil section and the pressure of the mixed liquid section, and calculating the pressure of the mixed liquid section by adopting the segmentation method.

Inventors

HUANG SHIZHEN
LIU YULIN
LIU YONGFU
LUO SHENCHAO
LI HONG
WU MEILIAN
YAN NAN
PENG PENG
ZHANG LEI
DU XIAORONG

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241108

Claims (10)

1. A method of calculating a bottom hole flow pressure of an oil well, comprising the steps of: Dividing an oil well with high gas-liquid ratio into a mixed liquid section, a foam pure oil section and a pure gas section from bottom to top; Respectively calculating the pressure of the foam pure oil section and the pressure of the pure gas section; calculating the pressure of the mixed liquid section according to the pressure of the obtained foam pure oil section and the pressure of the pure gas section; and calculating the bottom hole flow pressure of the target oil well according to the obtained pure gas section pressure, the foam pure oil section pressure and the mixed liquid section pressure.
2. The method for calculating the bottom hole flow pressure of an oil well according to claim 1, wherein the specific method for calculating the pressure of the foam pure oil section is as follows: acquiring the liquid level difference and the sleeve pressure difference of the current working liquid level of the target oil well; Calculating the fluid density of the foam pure oil section according to the obtained liquid level difference and the sleeve pressure difference; and calculating the pressure of the foam pure oil section according to the fluid density of the obtained foam pure oil section.
3. The method for calculating the bottom hole flow pressure of the oil well according to claim 2, wherein the liquid level difference and the sleeve pressure difference of the current working liquid level of the target oil well are obtained, and the method is as follows: testing the current working fluid level of the target oil well to obtain the initial working fluid level depth and the initial casing pressure; Closing the sleeve air release valve, and after the sleeve pressure rising amount reaches a set value, retesting the working fluid level of the target oil well to obtain the depth of the working fluid level and the sleeve pressure; And respectively calculating the liquid level difference and the sleeve pressure difference according to the obtained working liquid level depth, the sleeve pressure, the initial working liquid level depth and the initial sleeve pressure.
4. The method for calculating the bottom hole flow pressure of an oil well according to claim 1, wherein the pressure of the pure gas section is calculated by the following specific method: an initial working fluid level depth and an initial casing pressure of a current working fluid level of a target oil well are obtained, And calculating the pressure of the pure gas section according to the obtained initial working fluid level depth and the initial casing pressure.
5. The method for calculating the bottom hole flow pressure of the oil well according to claim 1, wherein in the step 2, the pressure of the mixed liquid section is calculated by the following specific method: calculating the pump intake pressure according to the obtained pressure of the foam pure oil section and the pressure of the pure gas section; Segmenting a mixed liquid section from a pump inlet to a well bottom according to a set step length to obtain a plurality of segments; calculating the pressure of the first segmented liquid column using the pump intake pressure; calculating a second segmented liquid column pressure using the first segmented liquid column pressure; calculating the liquid column pressure of a third section by using the second section hydraulic pressure, and sequentially calculating to obtain the liquid column pressure of each section; And summing the pressures of all the segmented liquid columns to obtain the pressure of the mixed liquid section.
6. The method of calculating the bottom hole flow pressure of an oil well according to claim 5, wherein the pump intake pressure is used to calculate the pressure of the first segmented liquid column by: Obtaining the density of crude oil by utilizing the suction pressure of a pump and combining the relationship curve of the density and the pressure of crude oil in a stratum; calculating the crude oil density of the first sectional liquid column according to the crude oil density; calculating the pressure of the first section liquid column according to the crude oil density of the obtained first section liquid column; The method for calculating the pressure of the second sectional liquid column by using the pressure of the first sectional liquid column comprises the following specific steps: Calculating the initial end pressure of the second sectional liquid column by using the pump suction pressure and the first sectional liquid column pressure; obtaining the crude oil density corresponding to the section by utilizing the obtained initial end pressure and combining the stratum crude oil density and pressure relation curve; Calculating to obtain the second sectional liquid column pressure by using the obtained crude oil density; the third section liquid column pressure is calculated by utilizing the second section hydraulic pressure, and the specific method is as follows: Calculating the initial end pressure of the third sectional liquid column by using the pump suction pressure, the first sectional liquid column pressure and the second sectional liquid column pressure; obtaining the crude oil density corresponding to the section by utilizing the obtained initial end pressure and combining the stratum crude oil density and pressure relation curve; and calculating to obtain the third sectional liquid column pressure by using the obtained crude oil density.
7. A system for calculating a bottom hole flow pressure of an oil well, comprising: the sectioning unit is used for dividing the high gas-liquid ratio oil well into a mixed liquid section, a foam pure oil section and a pure gas section from bottom to top; the pressure calculation unit is used for calculating the pressure of the foam pure oil section and the pressure of the pure gas section respectively; calculating the pressure of the mixed liquid section according to the pressure of the obtained foam pure oil section and the pressure of the pure gas section; And the bottom hole flow pressure calculation unit is used for calculating the bottom hole flow pressure of the target oil well according to the obtained pure gas section pressure, the foam pure oil section pressure and the mixed liquid section pressure.
8. A computer device, comprising: A processor adapted to execute a computer program; a computer readable storage medium having stored therein a computer program which, when executed by the processor, performs the method of any of claims 1-6.
9. A computer readable storage medium storing a computer program, which when executed by a processor implements the method according to any one of claims 1-6.
10. A computer program product, characterized in that the computer program product comprises a computer program which, when executed by a processor, implements the method according to any of claims 1-6.

Description

Method, system, equipment and medium for calculating bottom hole flow pressure of oil well Technical Field The invention belongs to the technical field of oil well detection, and particularly relates to a method, a system, equipment and a medium for calculating bottom hole flow pressure of an oil well. Background The oil pumping well and the electric pump well cannot directly test the bottom hole flowing pressure due to pipe columns, and the flowing pressure can be calculated through the working fluid level, the fluid density in a shaft and the casing pressure. However, for the oil pumping well and the electric pump well with high gas-liquid ratio, the wellhead pressure is lower in the general production process, the well bore degassing can be necessarily caused, the gas and the liquid form a foam pure oil section in the annular space of the sleeve, so that the density change of the well bore fluid is severe, the calculated bottom hole flow pressure error is large, the significance on the production guidance is smaller, and even the dynamic misjudgment on the pressure change of the oil well is caused. Disclosure of Invention The invention aims to provide a method, a system, equipment and a medium for calculating the bottom-hole flow pressure of an oil well, which solve the defect of large error in the existing high gas-liquid ratio oil well bottom-hole flow pressure calculation method, and can accurately calculate the density of each flow section of a shaft, thereby accurately calculating the bottom-hole flow pressure, and further solving the defect that an oil pumping unit and an electric pump well cannot directly test the bottom-hole flow pressure due to pipe columns and accurately master the production dynamics of the oil well. In order to achieve the above purpose, the invention adopts the following technical scheme: The invention provides a method for calculating the bottom hole flow pressure of an oil well, which comprises the following steps: Dividing an oil well with high gas-liquid ratio into a mixed liquid section, a foam pure oil section and a pure gas section from bottom to top; Respectively calculating the pressure of the foam pure oil section and the pressure of the pure gas section; calculating the pressure of the mixed liquid section according to the pressure of the obtained foam pure oil section and the pressure of the pure gas section; and calculating the bottom hole flow pressure of the target oil well according to the obtained pure gas section pressure, the foam pure oil section pressure and the mixed liquid section pressure. Preferably, the specific method for calculating the pressure of the foam pure oil section is as follows: acquiring the liquid level difference and the sleeve pressure difference of the current working liquid level of the target oil well; Calculating the fluid density of the foam pure oil section according to the obtained liquid level difference and the sleeve pressure difference; and calculating the pressure of the foam pure oil section according to the fluid density of the obtained foam pure oil section. Preferably, the liquid level difference and the sleeve pressure difference of the current working liquid level of the target oil well are obtained, and the specific method is as follows: testing the current working fluid level of the target oil well to obtain the initial working fluid level depth and the initial casing pressure; Closing the sleeve air release valve, and after the sleeve pressure rising amount reaches a set value, retesting the working fluid level of the target oil well to obtain the depth of the working fluid level and the sleeve pressure; And respectively calculating the liquid level difference and the sleeve pressure difference according to the obtained working liquid level depth, the sleeve pressure, the initial working liquid level depth and the initial sleeve pressure. Preferably, the pressure of the pure gas section is calculated by the following specific method: an initial working fluid level depth and an initial casing pressure of a current working fluid level of a target oil well are obtained, And calculating the pressure of the pure gas section according to the obtained initial working fluid level depth and the initial casing pressure. Preferably, in step 2, the pressure of the mixed liquid section is calculated by the following specific method: calculating the pump intake pressure according to the obtained pressure of the foam pure oil section and the pressure of the pure gas section; Segmenting a mixed liquid section from a pump inlet to a well bottom according to a set step length to obtain a plurality of segments; calculating the pressure of the first segmented liquid column using the pump intake pressure; calculating a second segmented liquid column pressure using the first segmented liquid column pressure; calculating the liquid column pressure of a third section by using the second section hydraulic pressure, and sequentially calcu