Method for acquiring performance parameters of drilling fluid and rheological sensor

Abstract

The invention relates to a drilling fluid performance parameter obtaining method and a rheological sensor, and relates to the technical field of detection.The drilling fluid performance parameter obtaining method comprises the following steps that performance parameters of a pipeline are obtained, and the performance parameters of the pipeline comprise the pipeline inner diameter, the pipeline length and the pipeline displacement; acquiring drilling fluid density and in-pipe pressure consumption; calculating to obtain the plastic viscosity of the drilling fluid; # imgabs0 #; wherein delta P is pressure consumption in the pipe, L is the length of the pipe column, Q is the displacement, rho d is the density of the drilling fluid, mu pv is the plastic viscosity of the drilling fluid, d is the inner diameter of the pipe column, a is the density correction coefficient, b is the friction coefficient in the pipe, c is the displacement correction coefficient, and eta is the wear coefficient. The plastic viscosity of the drilling fluid can be obtained only by measuring the pressure consumption in the pipe, and compared with the prior art, the operation is simpler and more convenient.

Description

Technical Field

[0001] The present application relates to the field of detection technologies, and in particular, to a method for obtaining performance parameters of drilling fluid and a rheological sensor. Background Art

[0002] Rheology is the science that studies the flow and deformation of substances, and its research objects include solids, liquids, and some multiphase systems. Rheological problems are widespread in many fields such as petroleum, chemical engineering, materials science, civil engineering, and even in daily life. In the petroleum industry, crude oil, fracturing fluid, drilling mud, etc. all exhibit complex rheological properties. Most of the crude oil produced in our country belongs to the easy-to-gel and high-viscosity variety, with poor fluidity and complex rheology. Therefore, rheology has become an important basic theory in the fields of oil development and pipeline transportation. Studying the rheology, modification methods, and their mechanisms of easy-to-gel and high-viscosity crude oil is also a research hotspot in the international petroleum industry.

[0003] The main application of rheological measurement is to guide the formulation design and quality control of displacement fluids. The main measurement parameters include plastic viscosity, apparent viscosity, dynamic shear force, and funnel viscosity. When measuring the above performance parameters, a rheological sensor is used. This instrument is a device specifically used to measure the viscosity of fluids. In the prior art, when obtaining the plastic viscosity, multiple values need to be measured in real time (such as instantaneous velocity gradient, shear stress value). This method requires setting multiple sensing elements to obtain the corresponding parameters, and the method of obtaining performance parameters is relatively troublesome. Summary of the Invention

[0004] The present application provides a method for obtaining performance parameters of drilling fluid and a rheological sensor, which do not require real-time measurement of multiple parameters and are easier to operate.

[0005] In a first aspect, the method for obtaining performance parameters of drilling fluid provided by the present application adopts the following technical solution: A method for obtaining performance parameters of drilling fluid, comprising the following steps: Obtain the performance parameters of the pipeline, where the performance parameters of the pipeline include the inner diameter of the pipeline, the length of the pipeline, and the pipeline displacement; Obtain the density of the drilling fluid and the pressure loss in the pipe; Calculate the plastic viscosity of the drilling fluid; ; where, ΔP is the pressure loss in the pipe, L is the length of the pipe string, Q is the displacement, ρ d is the density of the drilling fluid, μ pv is the plastic viscosity of the drilling fluid, d is the inner diameter of the pipe string, a is the density correction coefficient, b is the friction coefficient in the pipe, c is the displacement correction coefficient, and η is the wear coefficient.

[0006] Further, the density correction coefficient is set as: Among them, a0 is an empirical value, T is the bottom-hole temperature, T0 is the rated temperature of the instrument, and αa is the fitting density correction coefficient.

[0007] Furthermore, the value range of the density correction coefficient is set to 0.4 - 2.0.

[0008] Furthermore, the displacement correction coefficient is set to 1.8 or 1.9.

[0009] Furthermore, the friction coefficient inside the pipe is set as: b = 24 / Re; where Re is the Reynolds number.

[0010] In a second aspect, the rheological sensor provided by the present application adopts the following technical solution: A rheological sensor includes an industrial control computer, a pipeline, and pressure sensors arranged at both ends of the pipeline. The industrial control computer is preset with a computer program. When the industrial control computer executes the computer program, the above-mentioned acquisition method is realized.

[0011] In summary, the present application includes at least one of the following beneficial technical effects: 1. The working principle of the rheological sensor in the present application is based on the relationship between the pressure loss generated during the flow of the fluid and the fluid viscosity. The pressure loss generated by the fluid after passing through the instrument is measured by the pressure sensors at both ends, and this data is used to calculate the viscosity of the fluid.

[0012] 2. The present application obtains the plastic viscosity of the drilling fluid by setting a formula, and the density correction coefficient and displacement correction coefficient are included in the formula to correct the output result. After obtaining the performance parameters of the pipeline and the density of the drilling fluid, only the pressure loss inside the pipe needs to be measured to obtain the plastic viscosity of the drilling fluid. Compared with the prior art, the operation is simpler and more convenient.

[0013] 3. The density correction coefficient in the present application is obtained by fitting at a specific temperature and specific viscosity, simulating a high-temperature environment. By setting the density correction coefficient, during the calculation, data correction of the drilling fluid density based on the bottom-hole temperature can be performed, thereby ensuring the accuracy of the measurement result. Description of the Drawings

[0014] Figure 1 is a relationship diagram between the plastic viscosity and the pressure loss in the present application; Figure 2 is a relationship diagram between the density correction coefficient and the pressure loss in the present application; Figure 3 is a relationship diagram between the density correction coefficient and the apparent viscosity in the present application; Figure 4 It is a relationship diagram between the density correction coefficient and the dynamic shear force in this application; Detailed implementation manners The following will combine the attached Figures 1-4 Describe the technical solution of this application clearly and completely. The following embodiments are exemplary and are only used to explain this application, and cannot be construed as a limitation to this application. In the following description, the same reference signs are used to represent the same or equivalent elements, and repeated descriptions are omitted.

[0015] In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when this application product is normally placed, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to this application.

[0016] In addition, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific situations.

[0017] It should also be further understood that the term "and / or" used in the description of this application specification and the corresponding claims refers to any combination and all possible combinations of one or more of the listed items.

[0018] A rheological sensor includes an industrial control computer, a pipeline, and pressure sensors arranged at both ends of the pipeline. A computer program is preset in the industrial control computer for receiving the pressure data transmitted by the pressure sensors at both ends of the pipeline.

[0019] The rheological sensor can measure and obtain the performance parameters of the drilling fluid. When it is necessary to obtain the performance parameters of the drilling fluid, the rheological sensor is arranged in the well. One pressure sensor measures the pressure of the lower cylinder of the pipeline (denoted as P1), and the other sensor measures the pressure of the upper cylinder of the pipeline (denoted as P2). The pressures measured by the two pressure sensors will be input into the industrial control computer. After being analyzed by the industrial control computer, the plastic viscosity of the drilling fluid is obtained.

[0020] Furthermore, this application also discloses a method for obtaining the performance parameters of the drilling fluid, including the following steps: Obtain the performance parameters of the pipeline; Among them, the performance parameters of the pipeline include the inner diameter of the pipeline, the length of the pipeline, and the pipeline displacement. The inner diameter of the pipeline, the length of the pipeline, and the pipeline displacement are determined after the pipeline is selected. In a specific embodiment, the inner diameter of the pipeline is r = 25 mm; the length of the pipeline is L = 1 m, and the pipeline displacement is 1.9635 L. In another specific embodiment, the performance parameters of the pipeline can also be further adjusted according to the actual situation.

[0021] Obtain the density of the drilling fluid and the pressure loss in the pipe; The density of the drilling fluid and the pressure loss in the pipe are both obtained through actual measurement. In a specific embodiment, the density of the drilling fluid is 1.5 g / cm³, the flow rate of the drilling fluid is 10 L / s, and the pressure loss in the pipe ΔP = P1 - P2, which is a dynamic value. The measured density of the drilling fluid and the pressure loss in the pipe are both input into the industrial control computer.

[0022] Calculate the plastic viscosity of the drilling fluid; ; Among them, ΔP is the pressure loss in the pipe, L is the length of the pipe string, Q is the displacement, ρ d is the density of the drilling fluid, μ pv is the plastic viscosity of the drilling fluid, d is the inner diameter of the pipe string, a is the density correction coefficient, b is the friction coefficient in the pipe, c is the displacement correction coefficient, and η is the wear coefficient.

[0023] The above formula is preset in the industrial control computer. Substituting the obtained parameters into the formula, the relationship between the pressure loss and the plastic viscosity of the drilling fluid under the condition that the density of the drilling fluid is 1.5 g / cm³ can be obtained, that is, only by measuring the pressure loss, the plastic viscosity of the drilling fluid can be calculated. The measurement method is simpler and more efficient. The specific measurement results are as Figure 1 shown.

[0024] It should be noted that the performance parameters of the drilling fluid also include the funnel viscosity, apparent viscosity, and dynamic shear force. Among them, the slope between the plastic viscosity and the pressure loss is the dynamic shear force. The funnel viscosity and apparent viscosity are measured by other equipment and are trimmed in real time. Usually, the slope of the change of the funnel viscosity and apparent viscosity is close to the plastic viscosity.

[0025] Furthermore, the density correction coefficient is set to .

[0026] Among them, a0 is an empirical value, T is the bottom hole temperature, T0 is the rated temperature of the instrument, and α a is the fitted density correction coefficient, which is obtained by linearly fitting the scatter points of the correction ratio of each temperature based on the rated temperature of the instrument through on-site heating measurement of the drilling fluid.

[0027] The density of the drilling fluid is affected by temperature. Due to the material of the instrument components, it is impossible to simulate a high-temperature environment. By setting a density correction coefficient, during calculation, data correction of the drilling fluid density based on the bottom-hole temperature can be performed, thereby ensuring the accuracy of the measurement results.

[0028] Correspondingly, in a specific embodiment, the value range of the density correction coefficient is set to 0.4 - 2.0. The value range of the bottom-hole temperature is set to 30 - 70 °C.

[0029] Correspondingly, when the bottom-hole temperatures are 30 °C, 50 °C, and 70 °C, the relationships between the real-time density correction coefficient and the pressure loss, apparent viscosity, and dynamic shear force are shown successively as Figure 2 , Figure 3 , Figure 4 shown (it should be noted that the correction coefficient in the figure is the density correction coefficient).

[0030] Referring to Figure 2 , the change of the density correction coefficient measured by the pressure loss at different temperatures is not obvious. Within a certain range, the density correction coefficient is mainly positively correlated with the pressure loss value and tends to be stable after exceeding a certain threshold.

[0031] Referring to Figure 3 , as the temperature rises, the thermal motion of fluid molecules will intensify, the intermolecular interaction force will weaken, the density correction coefficient of the measured value increases, and it is positively correlated with the apparent viscosity.

[0032] Referring to Figure 4 , as the temperature rises, the measured density correction coefficient increases, the density correction coefficient is positively correlated with the dynamic shear force. When the temperature exceeds a certain threshold, the automatic measurement value approaches the manual measurement value, and the density correction coefficient is negatively correlated with the dynamic shear force.

[0033] Furthermore, the displacement correction coefficient c is a coefficient used to correct the change of the drilling fluid displacement under different conditions. The displacement correction coefficient c = actual displacement / average displacement. The actual operation displacement is obtained through on-site drilling equipment, and the average displacement is affected by the pumping power of the drilling fluid measuring instrument. In a specific embodiment, the displacement correction coefficient is set to 1.8 or 1.9, and the default setting is 1.8.

[0034] Furthermore, the in-tube friction coefficient is set to b = 24 / Re; where Re is the Reynolds number.

[0035] It should be noted that the in-tube friction coefficient here does not refer to the wall friction coefficient, but the friction coefficient between substances inside the in-tube fluid. This coefficient is related to the Reynolds number Re.

[0036] Furthermore, the inner diameter of the pipe string is corrected by the wear coefficient η. As the instrument is used, the inner wall of the hose in the instrument is eroded and worn by the drilling fluid, resulting in an increase in the inner diameter of the pipe string. The setting of the wear coefficient is mainly related to the service time of the hose component in the instrument and is calculated from the subsequent regularly measured values by manual measurement and the rated value at the factory.

[0037] The embodiments of the specific implementation manners are all preferred embodiments of the present application, and do not limit the protection scope of the present application accordingly. The same components are denoted by the same reference numerals. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A method for obtaining drilling fluid performance parameters, characterized in that: The following steps are involved: Acquiring performance parameters of the pipeline, wherein the performance parameters of the pipeline include the inner diameter of the pipeline, the length of the pipeline, and the displacement of the pipeline; Obtain drilling fluid density and pressure loss in pipe; The plastic viscosity of the drilling fluid is calculated; ； Among them, ΔP is the pressure loss in the tube, L is the length of the tube, Q is the displacement, ρ d is the density of drilling fluid, μ pv is the plastic viscosity of the drilling fluid, d is the inner diameter of the pipe, a is the density correction factor, b is the friction coefficient inside the pipe, c is the displacement correction factor, and η is the wear coefficient.

2. The acquisition method according to claim 1, characterized in that: The density correction factor is set as: ； Among them, a0 is the empirical value, T is the bottom hole temperature, T0 is the rated temperature of the instrument, and αa is the fitted density correction coefficient.

3. The acquisition method according to claim 2, characterized in that: The density correction coefficient is set in the range of 0.4 to 2.

0.

4. The acquisition method according to claim 2, characterized in that: The bottom hole temperature is set in the range of 30 to 70°C.

5. The acquisition method according to claim 1, characterized in that: The displacement correction coefficient is set to 1.8 or 1.

9.

6. The acquisition method according to claim 1, characterized in that: The friction coefficient in the tube is set to: b = 24 / Re; Where Re is the Rayleigh number.

7. A rheological sensor, characterized in that: It comprises an industrial computer, a pipeline and pressure sensors arranged at both ends of the pipeline. The industrial computer is preset with a computer program. When the industrial computer executes the computer program, the acquisition method according to any one of claims 1 to 6 is implemented.

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