Method for predicting distribution of rock debris in well, processor, device and storage medium

Abstract

The invention provides a method for predicting distribution of cuttings in a well, a processor, a device and a storage medium, and belongs to the technical field of oil drilling, and the method comprises the following steps: based on a corresponding relation between a predetermined hole drift angle and a cuttings bed volume, according to the cuttings bed total volume, calculating the cuttings bed volume; obtaining a current cuttings bed volume and a current cuttings bed height corresponding to each hole drift angle well section in all well sections; based on the corresponding relation between the predetermined hole drift angle and the rock debris particle volume, the current rock debris particle volume and the current rock debris particle volume concentration corresponding to the suspension layer of each hole drift angle well section are obtained according to the rock debris particle total volume; based on a preset solid-liquid two-phase flow model, according to the current cuttings bed height and the current cuttings particle volume concentration, the predicted cuttings bed height corresponding to each hole drift angle well section of the target well and the predicted cuttings particle volume concentration corresponding to the suspension layer of each hole drift angle well section are determined. The method can predict the distribution condition of the rock debris in the well in real time.

Description

Technical Field

[0001] The present application relates to the field of oil drilling technology, and in particular to a method for predicting cuttings distribution in a well. Background Art

[0002] During the drilling process, cuttings beds are often formed in the medium and large well inclination sections (30-90 degrees), and the distribution of cuttings beds in the wellbore is unknown. When drilling is stopped and the drilling operation is carried out, if the cuttings bed in the wellbore accumulates too much, it will cause difficulties in drilling and even mechanical drill jamming. Therefore, it is necessary to predict the distribution of cuttings beds in the wellbore during drilling conditions, and use this as a basis to decide whether it is safe to carry out the drilling operation. If the risk of pulling out the drill is too high, relevant measures can be taken based on the predicted cuttings bed distribution to reduce the height of the cuttings bed and reduce the risk of drill jamming. Therefore, how to predict the distribution of cuttings in the well is an urgent problem to be solved. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a method, processor, device and storage medium for predicting the distribution of rock cuttings in a well, so as to solve the problem of how to predict the distribution of rock cuttings in a well in the prior art.

[0004] In order to achieve the above-mentioned purpose, a first aspect of an embodiment of the present application provides a method for predicting cuttings distribution in a well, the method comprising:

[0005] During the drilling process of the target well, the total volume of the cuttings bed of all sections of the target well within a preset time period, the total volume of the cuttings particles in the suspension layer of all sections, the cross-sectional area of ​​the cuttings bed of each section of the target well at a well angle, and the annular volume of each section at a well angle are obtained;

[0006] Based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, the current cuttings bed volume of the cuttings bed corresponding to each well inclination angle section in all well sections is obtained;

[0007] Determine the current cuttings bed height corresponding to each well inclination angle according to the current cuttings bed volume and cross-sectional area;

[0008] Based on the predetermined correspondence between the well inclination angle and the volume of the rock cutting particles, according to the total volume of the rock cutting particles, the current volume of the rock cutting particles corresponding to the suspension layer of each well section with a well inclination angle is obtained;

[0009] Determine the difference between the annular volume and the current cuttings bed volume to obtain the suspended layer volume of the suspended layer at each well inclination angle section;

[0010] According to the volume of the suspension layer and the current volume of the cuttings particles, the current volume concentration of the cuttings particles corresponding to the suspension layer in each well section with a wellbore inclination angle is determined;

[0011] Based on the preset solid-liquid two-phase flow model, the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section are determined according to the current cuttings bed height and the current cuttings particle volume concentration.

[0012] In an embodiment of the present application, obtaining the total volume of the cuttings bed includes: obtaining the mass of the returned cuttings collected at the wellhead of the target well within a preset time period and the drilling speed of the drilling equipment; determining the returned cuttings volume of the returned cuttings based on the mass of the returned cuttings and the preset cuttings density; determining the theoretical cuttings volume of the target well based on the drilling speed and the preset time period; determining the difference between the theoretical cuttings volume and the returned cuttings volume to obtain the total cuttings volume of the cuttings of all well sections; determining the product value of the total cuttings volume and the preset proportional coefficient to obtain the cuttings volume in the cuttings bed of all well sections; determining the ratio of the cuttings volume to the preset solid content parameter to obtain the total volume of the cuttings bed.

[0013] In the embodiment of the present application, obtaining the total volume of rock cuttings particles includes: determining the difference between the total volume of rock cuttings and the volume of rock cuttings to obtain the total volume of rock cuttings particles.

[0014] In an embodiment of the present application, based on a predetermined correspondence between the inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, the current cuttings bed volume corresponding to each inclination angle section in all the well sections is obtained, including: based on the predetermined correspondence between the inclination angle and the cuttings bed volume, determining the initial cuttings bed volume corresponding to each inclination angle section according to the cuttings bed volume of the preset 90-degree inclination angle section; determining the sum of the initial cuttings bed volumes corresponding to each inclination angle section in all the well sections to obtain the total volume of the initial cuttings bed; when the difference between the total volume of the initial cuttings bed and the total volume of the cuttings bed is greater than or equal to a preset error threshold, adjusting the cuttings bed volume of the preset 90-degree inclination angle section until the difference between the sum of the cuttings bed volumes corresponding to each inclination angle section and the total volume of the cuttings bed is less than the preset error threshold to obtain the current cuttings bed volume.

[0015] In an embodiment of the present application, the current cuttings bed height corresponding to each well inclination angle section is determined based on the current cuttings bed volume and cross-sectional area, including: determining the ratio of the current cuttings bed volume to the cross-sectional area to obtain the cuttings bed height corresponding to each well inclination angle section.

[0016] In an embodiment of the present application, based on the predetermined correspondence between the well inclination angle and the volume of rock cuttings particles, the current rock cuttings particle volume corresponding to the suspended layer of each well inclination angle section is obtained according to the total volume of rock cuttings particles, including: based on the predetermined correspondence between the well inclination angle and the volume of rock cuttings particles, the initial rock cuttings particle volume corresponding to each well inclination angle section is determined according to the rock cuttings particle volume of the preset 90-degree well inclination angle section; the sum of the initial rock cuttings particle volumes corresponding to each well inclination angle section in all well sections is determined to obtain the total volume of initial rock cuttings particles; when the difference between the initial total volume of rock cuttings particles and the total volume of rock cuttings particles is greater than or equal to a preset error threshold, the rock cuttings particle volume of the preset 90-degree well inclination angle section is adjusted until the difference between the sum of the initial rock cuttings particle volumes corresponding to each well inclination angle section and the total volume of rock cuttings particles is less than the preset error threshold to obtain the current rock cuttings particle volume.

[0017] In an embodiment of the present application, the current rock cutting particle volume concentration corresponding to the suspended layer of each well inclination angle section is determined according to the suspended layer volume and the current rock cutting particle volume, including: determining the ratio of the current rock cutting particle volume to the suspended layer volume to obtain the rock cutting particle volume concentration.

[0018] In an embodiment of the present application, based on a preset solid-liquid two-phase flow model, according to the current cuttings bed height and the current volume concentration of cuttings particles, determining the predicted cuttings bed height corresponding to each wellbore inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each wellbore inclination section includes: obtaining drilling operating parameters; based on a preset solid-liquid two-phase flow model, according to the drilling operating parameters, the current cuttings bed height and the current volume concentration of cuttings particles, determining the predicted cuttings bed height corresponding to each wellbore inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each wellbore inclination section.

[0019] A second aspect of an embodiment of the present application provides a processor configured to execute the above-mentioned method for predicting cuttings distribution in a well.

[0020] A third aspect of an embodiment of the present application provides a device for predicting the distribution of cuttings in a well, the device comprising:

[0021] A data acquisition module is used to acquire, during the drilling process of the target well, the total volume of the cuttings bed of all well sections of the target well within a preset time period, the total volume of the cuttings particles in the suspension layer of all well sections, the cross-sectional area of ​​the cuttings bed of each well section with a well deviation angle of the target well, and the annular volume of each well section with a well deviation angle;

[0022] A cuttings bed volume determination module is used to obtain the current cuttings bed volume corresponding to each well section with a well inclination angle in all well sections according to the total volume of the cuttings bed based on the predetermined correspondence between the well inclination angle and the cuttings bed volume;

[0023] A cuttings bed height determination module is used to determine the current cuttings bed height of the cuttings bed corresponding to each well section with a well inclination angle according to the cross-sectional area based on the corresponding relationship between the current cuttings bed height and the cross-sectional area;

[0024] A cuttings particle volume determination module is used to obtain the current cuttings particle volume corresponding to the suspension layer of each well section with a well inclination angle according to the total volume of the cuttings particles based on the predetermined correspondence between the well inclination angle and the cuttings particle volume;

[0025] A suspension layer volume determination module is used to determine the difference between the annular volume and the current cuttings bed volume to obtain the suspension layer volume of the suspension layer in each well section with a well inclination angle;

[0026] A cuttings particle volume concentration determination module is used to determine the current cuttings particle volume concentration corresponding to the suspension layer of each well section with a wellbore inclination angle according to the suspension layer volume and the current cuttings particle volume;

[0027] The data prediction module is used to determine the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section based on the preset solid-liquid two-phase flow model and the current cuttings bed height and the current cuttings particle volume concentration.

[0028] A fourth aspect of an embodiment of the present application provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute the above-mentioned method for predicting cuttings distribution in a well.

[0029] The above technical scheme takes into account the two existing forms of cuttings, cuttings bed and suspended layer. Based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, the current cuttings bed volume corresponding to each well inclination angle section in all well sections is obtained; further, the current cuttings bed height of the cuttings bed corresponding to each well inclination angle section is obtained, so that the cuttings bed height of each well section can be accurately calculated. Based on the predetermined correspondence between the well inclination angle and the cuttings particle volume, according to the total volume of the cuttings particles, the current cuttings particle volume corresponding to the suspended layer of each well inclination angle section is obtained, and then the current cuttings particle volume concentration corresponding to the suspended layer of each well inclination angle section is obtained, so that the cuttings particle volume concentration of each well section can be accurately calculated. The present application uses a preset solid-liquid two-phase flow model, the current cuttings particle volume concentration and the current cuttings bed height to predict the real-time cuttings particle volume concentration and the real-time cuttings bed height, and also improves the accuracy of the prediction results of the cuttings distribution in the well, and uses this as a basis to decide whether the drilling operation can be carried out safely, thereby improving the safety of production operations.

[0030] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

[0032] Figure 1 A schematic diagram of a process for predicting the distribution of cuttings in a well in an embodiment of the present application is shown schematically;

[0033] Figure 2 The schematic diagram shows a structural block diagram of a device for predicting cuttings distribution in a well in one embodiment of the present application. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0035] It should be noted that the acquisition, transmission, storage, use, and processing of data in the technical solution of this application are in compliance with the relevant provisions of national laws and regulations. In the embodiments of this application, some existing solutions in the industry such as certain software, components, and models may be mentioned, which should be considered as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of this application, but it does not mean that the applicant has or will necessarily use the solution.

[0036] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0037] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0038] Figure 1 The schematic diagram of the process flow for predicting the distribution of cuttings in a well in one embodiment of the present application is shown schematically. Figure 1 As shown, the embodiment of the present application provides a method for predicting the distribution of cuttings in a well, which is described by taking the method applied to a processor as an example. The method may include the following steps:

[0039] Step S101, during the drilling process of the target well, obtain the total volume of the cuttings bed of all sections of the target well within a preset time period, the total volume of the cuttings particles in the suspended layer of all sections, the cross-sectional area of ​​each well inclination angle section of the target well, and the annulus volume of each well inclination angle section.

[0040] Step S102, based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, the current cuttings bed volume corresponding to each well inclination angle section in all well sections is obtained.

[0041] Step S103, determining the current cuttings bed height corresponding to each well section with a well inclination angle according to the current cuttings bed volume and cross-sectional area.

[0042] Step S104, based on the predetermined correspondence between the well inclination angle and the volume of the rock cuttings particles, according to the total volume of the rock cuttings particles, the current volume of the rock cuttings particles corresponding to the suspension layer of each well section with a well inclination angle is obtained.

[0043] Step S105, determining the difference between the annular space volume and the current cuttings bed volume to obtain the suspended layer volume of the suspended layer in each well section with a well inclination angle.

[0044] Step S106, determining the current volume concentration of rock cuttings particles corresponding to the suspension layer of each well section with a wellbore inclination angle according to the volume of the suspension layer and the current volume of rock cuttings particles.

[0045] Step S107, based on the preset solid-liquid two-phase flow model, according to the current cuttings bed height and the current cuttings particle volume concentration, determine the predicted cuttings bed height corresponding to each well inclination angle section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination angle section.

[0046] It can be understood that there are two types of distribution forms of cuttings in the well, one is in the cuttings bed and the other is in the suspended layer. The cuttings bed is one of the distribution forms of cuttings in the well. At the same time, the cuttings bed is not a solid with only cuttings particles. The gaps between the particles are filled with drilling fluid. The total volume of the cuttings bed refers to the total volume of the cuttings bed in all sections of the well. The method of obtaining it is to obtain the sum of the cuttings in the well by the difference between the theoretical cuttings volume calculated in advance and the cuttings volume measured in advance, and then multiply the sum of the cuttings in the well by the cuttings ratio coefficient of the cuttings bed to obtain the total volume of the cuttings in the cuttings bed, and then obtain the total volume of the cuttings bed by the ratio of the total volume of the cuttings in the cuttings bed to the solid content parameter of the drilling fluid. The current cuttings bed volume refers to the cuttings bed volume currently calculated. The current cuttings bed height refers to the cuttings bed height currently calculated. The suspended layer volume refers to the volume of the suspended layer in each section. The total volume of cuttings particles is the total volume of cuttings particles in the suspension layer of all well sections. The method of obtaining the total volume of cuttings particles is to obtain the total volume of cuttings particles according to the product of the total amount of cuttings in the well and the proportion coefficient of cuttings in the suspension layer. Another method of obtaining the total volume of cuttings particles is to obtain the total volume of cuttings particles by the difference between the total amount of cuttings in the well and the total volume of cuttings in the cuttings bed. The current volume of cuttings particles refers to the volume of cuttings in the suspension layer currently calculated. This cuttings is only in the suspension layer, not in the cuttings bed. The current volume concentration of cuttings particles refers to the volume concentration of cuttings in the suspension layer currently calculated. The cross-sectional area of ​​the cuttings bed refers to the cross-sectional area occupied by the cuttings bed, and the annular volume refers to the void volume between the casing and the wellbore. The annular volume in the well is occupied by the cuttings bed and the suspension layer volume. The cross-sectional area of ​​the cuttings bed is equal to the cross-sectional area of ​​the annular space minus the cross-sectional area of ​​the suspension layer. The predicted height of the cuttings bed refers to the height of the cuttings bed in the future. The predicted volume concentration of cuttings particles refers to the volume concentration of cuttings in the suspension layer in the future. The preset solid-liquid two-phase flow model is a predetermined model used to predict the height of the cuttings bed and the volume concentration of cuttings particles corresponding to the suspension layer, for example, it may be a transient two-layer cuttings transport model.

[0047] Specifically, during the drilling process of the target well, the processor obtains the total volume of the cuttings bed of all sections of the target well within a preset time period, the total volume of cuttings particles in the suspension layer of all sections, the cross-sectional area of ​​each well section of the target well, and the annular volume of each well section of the ... Based on the predetermined correspondence between the well inclination angle and the volume of the rock cuttings particles, the processor can obtain the current volume of the rock cuttings particles corresponding to the suspension layer of each well inclination angle section according to the total volume of the rock cuttings particles. The processor obtains the volume of the suspension layer of each well inclination angle section according to the difference between the annular volume and the current rock cuttings bed volume, and determines the current rock cuttings particle volume concentration corresponding to the suspension layer of each well inclination angle section according to the suspended layer volume and the current rock cuttings particle volume; so that the determined rock cuttings particle concentration of the current suspension layer can be input into the preset solid-liquid two-phase flow model to obtain the real-time rock cuttings particle concentration of the suspension layer. The processor also determines the predicted rock cuttings bed height corresponding to each well inclination angle section of the target well and the predicted rock cuttings particle volume concentration corresponding to the suspension layer of each well inclination angle section based on the preset solid-liquid two-phase flow model and the current rock cuttings bed height and the current rock cuttings particle volume concentration.

[0048] The above technical scheme takes into account the two existing forms of cuttings, cuttings bed and suspended layer. Based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, the current cuttings bed volume corresponding to each well inclination angle section in all well sections is obtained; further, the current cuttings bed height of the cuttings bed corresponding to each well inclination angle section is obtained, so that the cuttings bed height of each well section can be accurately calculated. Based on the predetermined correspondence between the well inclination angle and the cuttings particle volume, according to the total volume of the cuttings particles, the current cuttings particle volume corresponding to the suspended layer of each well inclination angle section is obtained, and then the current cuttings particle volume concentration corresponding to the suspended layer of each well inclination angle section is obtained, so that the cuttings particle volume concentration of each well section can be accurately calculated. The present application uses a preset solid-liquid two-phase flow model, the current cuttings particle volume concentration and the current cuttings bed height to predict the real-time cuttings particle volume concentration and the real-time cuttings bed height, and also improves the accuracy of the prediction results of the cuttings distribution in the well, and uses this as a basis to decide whether the drilling operation can be carried out safely, thereby improving the safety of production operations.

[0049] In one embodiment, obtaining the total volume of the cuttings bed may include: obtaining the mass of the returned cuttings collected at the wellhead of the target well within a preset time period and the drilling speed of the drilling equipment; determining the returned cuttings volume of the returned cuttings based on the mass of the returned cuttings and the preset cuttings density; determining the theoretical cuttings volume of the target well based on the drilling speed and the preset time period; determining the difference between the theoretical cuttings volume and the returned cuttings volume to obtain the total cuttings volume of the cuttings in all well sections; determining the product value of the total cuttings volume and a preset proportional coefficient to obtain the cuttings volume in the cuttings bed of all well sections; determining the ratio of the cuttings volume to a preset solid content parameter to obtain the total volume of the cuttings bed.

[0050] It can be understood that the total volume of cuttings refers to the total volume of the cuttings bed of all well sections in the well, and is also the difference between the theoretical cuttings volume and the returned cuttings volume. The cuttings volume is the volume of cuttings in the cuttings bed of all well sections. The returned cuttings refer to the cuttings brought up by the drilling equipment during the drilling process. The steps for measuring the quality of the returned cuttings are as follows: During the drilling process, the drilling fluid is circulated out of the well and then processed by a vibrating screen to remove the cuttings particles therein. After a simple transformation, a wet cuttings weighing device (drilling fluid is adsorbed on the cuttings at this time), a cuttings washing device (to wash away the drilling fluid), a cuttings rapid drying device, and a dry cuttings weighing device are added after the vibrating screen. After this series of operations, the quality of the returned cuttings in the preset time period is obtained. The preset cuttings density is the cuttings density obtained at the beginning of drilling, and the returned cuttings volume refers to the volume of cuttings brought up by the drilling equipment during drilling. Therefore, the present application can obtain the volume of the returned cuttings by dividing the mass of the returned cuttings by the cuttings density. The preset time period is mainly set according to the actual mechanical drilling speed on site. The time to collect 50kg or 100kg of wet cuttings can be set as a preset time period; or a preset time period determined by a fixed time, such as 0.5h collection. Collect a series of "returned cuttings volume" of continuous "preset time periods" and sum them up to obtain the "returned cuttings volume" in a drilling process. The drill bit cuts the formation to form cuttings particles. During the migration process, part of the cuttings particles are deposited on the lower side of the wellbore to form a cuttings bed, while part of the cuttings are carried to the wellhead by the drilling fluid. The theoretical cuttings volume refers to the volume of cuttings carried to the wellhead by the drilling fluid. Corresponding to the drilling process corresponding to the "returned cuttings volume", there is a mechanical drilling speed corresponding to the time point in the drilling process. The mechanical drilling speed is interpolated with time to form a function of the mechanical drilling speed relative to time. The theoretical cuttings volume can be obtained by integrating the relationship between the mechanical drilling speed and time. The preset solid content parameter refers to the percentage of the cuttings volume in the cuttings bed to the cuttings bed volume. When the "theoretical cuttings volume" is less than the "returned cuttings volume", a serious wellbore collapse occurs in the wellbore. At this time, a large amount of cuttings in the wellbore are not produced by the drill bit cutting the formation, but are formed by the original wellbore wall fragmentation and block falling. This part of the cuttings cannot be estimated theoretically. Therefore, measures should be taken as soon as possible to keep the wellbore stable, and then gradually circulate and clean the cuttings at the bottom of the well. When the "theoretical cuttings volume" is greater than or equal to the "returned cuttings volume", this is the normal drilling condition in most cases. The preset proportional coefficient and drilling parameters are related to the rheology of the drilling fluid. The drilling parameters include displacement, drill pipe speed, and mechanical drilling speed. The rheology of the drilling fluid includes viscosity, dynamic shear force, and static shear force. Therefore, the proportional coefficient is determined by the drilling parameters and the rheology of the drilling fluid.

[0051] Specifically, the processor first determines the amount of cuttings remaining in the wellbore: in order to predict the dynamic distribution of cuttings in the wellbore, the amount of cuttings remaining in the wellbore will be used as the initial value, but it needs to be processed. This part of the cuttings exists in two forms, the suspended cuttings in the circulation layer and the height of the cuttings bed deposited on the lower side of the wellbore. A part of the cuttings remaining in the wellbore forms a cuttings bed, and this proportion is related to the proportional coefficient and the actual well site. After determining the theoretical cuttings volume and the returned cuttings volume, the difference between the theoretical cuttings volume and the returned cuttings volume is obtained to obtain the total cuttings volume of the cuttings of all well sections; then, the cuttings volume in the cuttings bed of all well sections is obtained by multiplying the total cuttings volume and the preset proportional coefficient; because the cuttings bed is not a solid with only cuttings particles, the gaps between the particles are filled with drilling fluid, so the total volume of the cuttings bed at the bottom of the well is the total volume of the cuttings of the cuttings bed obtained above divided by the solid content coefficient.

[0052] In one embodiment, obtaining the total volume of rock cuttings particles includes: determining a difference between the total volume of rock cuttings and the volume of rock cuttings to obtain the total volume of rock cuttings particles.

[0053] Specifically, the total volume of the cuttings of the suspended particles plus the total volume of the cuttings of the cuttings bed is equal to the total volume of the cuttings, that is, the total volume of the cuttings of the suspended particles plus the total volume of the cuttings of the cuttings bed is equal to the difference between the "theoretical cuttings volume" and the "upward cuttings volume". Another total volume of cuttings forming suspended particles can be obtained according to the product of the suspended layer particle ratio coefficient and the total volume of cuttings of all well sections.

[0054] In one embodiment, based on the predetermined correspondence between the inclination angle and the cuttings bed volume, the current cuttings bed volume corresponding to each inclination angle section in all the well sections is obtained according to the total cuttings bed volume, including: based on the predetermined correspondence between the inclination angle and the cuttings bed volume, the initial cuttings bed volume corresponding to each inclination angle section is determined according to the cuttings bed volume of the preset 90-degree inclination angle section; the sum of the initial cuttings bed volumes corresponding to each inclination angle section in all the well sections is determined to obtain the total initial cuttings bed volume, and when the difference between the initial total cuttings bed volume and the total cuttings bed volume is greater than or equal to a preset error threshold, the cuttings bed volume of the preset 90-degree inclination angle section is adjusted until the difference between the sum of the cuttings bed volumes corresponding to each inclination angle section and the total cuttings bed volume is less than the preset error threshold to obtain the current cuttings bed volume.

[0055] It can be understood that there will be well sections with different well inclination angles in the well, and the current cuttings bed volume is the cuttings bed volume corresponding to each well section with well inclination angle in all well sections. The correspondence between the predetermined well inclination angle and the cuttings bed volume is the correspondence between the predetermined well inclination angle and the cuttings bed volume. The preset 90-degree well inclination angle well section cuttings bed volume is the preset 90-degree well inclination angle well section cuttings bed volume (the preset 90-degree well inclination angle well section is a horizontal section). This preset 90-degree well inclination angle well section cuttings bed volume is an undetermined value, but a preset value is set so that the cuttings bed volume corresponding to each well section with well inclination angle is calculated according to the preset 90-degree well inclination angle well section cuttings bed volume. The initial cuttings bed volume is the cuttings bed volume corresponding to each well section with well inclination angle calculated according to the preset 90-degree well inclination angle well section cuttings bed volume. The preset error threshold is a preset error threshold. This application sets this value to 0.001%, and it can also be set to other values ​​due to other accuracy requirements.

[0056] Specifically, the cuttings bed is distributed in the well section with a well inclination angle of 30-90 degrees. The total cuttings bed volume is known, and the cuttings bed distribution of each well section is solved. This requires iterative calculation. This application assumes the cuttings bed volume in the horizontal section (well inclination angle of 90 degrees) because the amount of cuttings deposited in the well section has a quantitative relationship with the well inclination angle. For a well section with a length of Δx, the deposited cuttings bed volume at different well inclination angles has the following quantitative relationship:

[0057] ΔV b,α =ΔV b,90 (1+0.005556α)[1+0.4sin(2α)] / 1.5

[0058] The processor first assumes that the well inclination angle is 90 degrees and the length of the well section is Δx, and the volume of the cuttings deposited is ΔV b,90 , then the cuttings volume of the well section corresponding to other well inclination angles can be obtained as ΔV b,α , sum the cuttings volume of all well sections V b,test , if V b,test If the total volume of the cuttings bed is less than the above calculated volume, then the assumed ΔV b,90 , continue the iterative calculation. b,test If the error with the total volume of the cuttings bed calculated above is less than 0.001%, the iteration is completed. The volume of the cuttings bed can be converted into the cuttings bed height h through the geometric relationship c,α .

[0059] The processor converts the volume of the cuttings bed into the height of the cuttings bed through geometric relationships. First, the cross-sectional area of ​​the cuttings bed must be calculated, and then the height of the cuttings bed corresponding to each well inclination angle is obtained based on the cross-sectional area of ​​the cuttings bed and the volume of the cuttings bed corresponding to each well inclination angle.

[0060] In one embodiment, based on the predetermined correspondence between the well inclination angle and the volume of rock cuttings particles, the current rock cuttings particle volume corresponding to the suspended layer of each well inclination angle section is obtained according to the total volume of rock cuttings particles, including: based on the predetermined correspondence between the well inclination angle and the volume of rock cuttings particles, the initial rock cuttings particle volume corresponding to each well inclination angle section is determined according to the rock cuttings particle volume of the preset 90-degree well inclination angle section; the sum of the initial rock cuttings particle volumes corresponding to each well inclination angle section in all the well sections is determined to obtain the total volume of initial rock cuttings particles; when the difference between the total volume of initial rock cuttings particles and the total volume of rock cuttings particles is greater than or equal to a preset error threshold, the rock cuttings particle volume of the preset 90-degree well inclination angle section is adjusted until the difference between the sum of the initial rock cuttings particle volumes corresponding to each well inclination angle section and the total volume of rock cuttings particles is less than the preset error threshold to obtain the current rock cuttings particle volume.

[0061] It can be understood that the correspondence between the predetermined well inclination angle and the volume of rock cuttings particles is the relationship between the predetermined well inclination angle and the volume of rock cuttings particles. The preset 90-degree well inclination angle well section rock cuttings particle volume is the volume of the rock cuttings of the suspended layer of the well section with a well inclination angle of 90 degrees. This preset 90-degree well inclination angle well section rock cuttings particle volume is an undetermined value, and it is just a preset value to calculate the rock cuttings particle volume corresponding to each well inclination angle well section based on the preset 90-degree well inclination angle well section rock cuttings particle volume. The initial rock cuttings particle volume is the rock cuttings particle volume corresponding to each well inclination angle well section calculated based on the preset 90-degree well inclination angle well section rock cuttings particle volume. The preset error threshold is a preset error threshold, and this application sets the value to 0.001%, and it can also be set to other values ​​due to other accuracy requirements.

[0062] Specifically, the method used to calculate the amount of suspended cuttings particles in the annular circulation layer above the cuttings bed is consistent with the calculation of the cuttings bed volume. For a well section with a length of ɑ, the volume of suspended cuttings particles in the circulation layer at different well inclination angles has the following quantitative relationship:

[0063] ΔV sp,α =ΔV sp,90 (1+0.005556α)[1+0.4sin(2α)] / 1.5

[0064] The processor first assumes that the well inclination angle is 90 degrees and the length of the well section is Δx, and the volume of the suspended cuttings is ΔV sp,90 , then the cuttings volume of the well section corresponding to other well inclination angles can be obtained as ΔV sp,α The sum of the cuttings volume of all well sections is V sp,test , if V sp,test is smaller than the total volume of rock cuttings particles, then the assumed ΔV is increased sp,90 , continue iterative calculation. sp,testWhen the error with the total volume of rock cuttings particles is less than 0.001%, the iteration is completed.

[0065] In one embodiment, the current rock cutting particle volume concentration corresponding to the suspended layer of each well section with a wellbore inclination angle is determined according to the suspended layer volume and the current rock cutting particle volume, including: determining the ratio of the current rock cutting particle volume to the suspended layer volume to obtain the rock cutting particle volume concentration.

[0066] Specifically, the product of the suspension layer volume and the rock debris particle volume concentration is the current rock debris particle volume, and thus the rock debris particle volume concentration can be obtained from the ratio of the current rock debris particle volume to the suspension layer volume.

[0067] In one embodiment, based on a preset solid-liquid two-phase flow model, according to the current cuttings bed height and the current volume concentration of cuttings particles, determining the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section includes: obtaining drilling condition parameters; based on a preset solid-liquid two-phase flow model, according to the drilling condition parameters, the current cuttings bed height and the current volume concentration of cuttings particles, determining the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section.

[0068] It can be understood that the current cuttings bed height refers to the cuttings bed height currently calculated. The current cuttings particle volume concentration refers to the current volume concentration of cuttings in the suspension layer calculated. The predicted cuttings bed height is the future cuttings bed height predicted by a preset solid-liquid two-phase flow model. The predicted cuttings particle volume concentration is the future cuttings particle volume concentration predicted by a preset solid-liquid two-phase flow model. Drilling operating parameters may include drilling fluid displacement, drill pipe size, drilling fluid rheology, inclination data, mechanical penetration rate, drill pipe speed, etc.

[0069] Specifically, the processor obtains the cuttings bed height and cuttings concentration of all sections of the entire wellbore. The cuttings bed height and cuttings concentration are different in sections with different well inclination angles. These results are the initial values ​​of the solid-liquid two-phase flow model. Next, the transient two-layer cuttings transport model will be used for calculation. In this way, the cuttings transport process in the wellbore during drilling conditions can be predicted in real time, and finally the cuttings distribution in the wellbore can be obtained.

[0070] The transient two-layer cuttings transport model can be as follows:

[0071]

[0072] -τ sbw S sb +τ sbsd S sbsd -F+v sb Φ sb

[0073]

[0074] -C f τ fw S sd -C f τ sbsd S sdsb -F cf -(v f -v sb )Φ sdf

[0075]

[0076] -C c τ cw S sd -C c τ sbsd S sbsd +F cf -(v c -v sb )Φ sdc

[0077] C, volume concentration; ρ, density; A, annulus cross-sectional area; v, velocity; p, pressure; subscript f represents fluid; c represents cuttings; sb represents cuttings bed, sd represents flow layer; F cf , multi-particle drag force; F, dry friction; θ, well inclination; τ, shear stress, subscript sbsd represents the interface between the two layers, fw represents the interface between the fluid in the circulation layer and the drill pipe and the well wall, cw represents the interface between the cuttings in the circulation layer and the drill pipe and the well wall, sbw represents the interface between the cuttings bed and the well wall and the drill pipe, Φ sdc ,Φ sdf and Φ sb is the mass exchange coefficient.

[0078] The model results are solved to obtain the distribution of cuttings in the wellbore corresponding to the drilling time and wellbore depth:

[0079] h c,α ~t,D m C α ~t,D m

[0080] t is the drilling time from the start of calculation D m , is the depth of each position of the wellbore, h c,α Real-time cuttings bed height for each well inclination angle, C α Real-time suspended layer cuttings volume concentration for each well inclination angle.

[0081] In a specific embodiment, a method for predicting cuttings distribution in a well is provided. The present application divides the cuttings distribution into two parts for detailed calculation. The two parts are the cuttings in the cuttings bed and the cuttings in the suspended layer. The sum of these two parts is the difference between the theoretical cuttings amount and the returned cuttings amount, that is, the difference between the theoretical cuttings amount that should be produced and the cuttings amount detected by the returned cuttings, that is, the total amount of cuttings existing at the bottom of the well. Then, the cuttings amount in the cuttings bed and the cuttings amount in the suspended layer are determined respectively according to the proportional coefficient, so that the cuttings amount of each can be obtained. When the cuttings amount of both is known, since the cuttings bed contains drilling fluid in addition to cuttings, the total volume of the cuttings bed can be obtained according to the solid content coefficient. Then, since the well sections have different well inclination angles, we need to obtain the cuttings bed volume of the well sections with different well inclination angles. Because in the correspondence between the predetermined well inclination angle and the cuttings bed volume, The variable is the well inclination angle, and the dependent variable is the cuttings bed volume at different well inclination angles, wherein the cuttings bed volume at the well section with a well inclination angle of 90 degrees is a preset value. Therefore, we obtain the cuttings bed volume of each well section based on the correspondence between the predetermined well inclination angle and the cuttings bed volume and the preset cuttings bed volume at the well section with a well inclination angle of 90 degrees. Then, the cuttings bed volume of each well section obtained based on the correspondence between the predetermined well inclination angle and the cuttings bed volume is superimposed to obtain the sum of the cuttings bed volumes of each well section under the condition of the preset cuttings bed volume at the well section with a well inclination angle of 90 degrees. This sum is compared with the total cuttings bed volume obtained previously based on the solid content coefficient. When the error between the two is greater than or equal to 0.001%, the preset cuttings bed volume of the well section with a well inclination angle of 90 degrees is adjusted until the error is less than 0.001%. Then, the cuttings bed volume corresponding to each well inclination angle can be obtained based on the adjusted cuttings bed volume at the well section with a well inclination angle of 90 degrees. The height of the cuttings bed corresponding to each well inclination angle is calculated based on the collective relationship between the volume of the cuttings bed and the cross-sectional area of ​​the cuttings bed. To calculate the concentration of suspended layer cuttings, it is necessary to first calculate the cuttings content of the suspended layer corresponding to different well inclination angles. Because in the correspondence between the predetermined well inclination angle and the cuttings volume in the suspended layer, the independent variable is the well inclination angle, and the dependent variable is the cuttings volume of the suspended layer at different well inclination angles, where the cuttings volume of the suspended layer section at 90-degree well inclination angle is a preset value. Based on the correspondence between the predetermined well inclination angle and the cuttings particle volume and the preset cuttings particle volume of the well section at 90-degree well inclination angle, we can calculate the cuttings volume of the suspended layer corresponding to each well inclination angle, and then calculate the cuttings concentration of the suspended layer corresponding to the predetermined well inclination angle according to the predetermined well inclination angle. The volume of cuttings in the suspended layer corresponding to each well inclination angle obtained by the correspondence between the inclination angle and the volume of cuttings in the suspended layer is superimposed and summed, and then the volume of cuttings in the suspended layer after summation is compared with the total volume of cuttings in the suspended layer previously obtained according to the proportional coefficient. When the error between the two is greater than or equal to 0.001%, the preset cuttings volume of the well section with a well inclination angle of 90 degrees is adjusted until the error is less than 0.001%. The volume of cuttings in the suspended layer corresponding to each well inclination angle can be obtained based on the adjusted cuttings volume of the well section with a well inclination angle of 90 degrees.The volume concentration of rock cuttings in the suspended layer corresponding to each well inclination angle is the volume of rock cuttings in the suspended layer corresponding to each well inclination angle divided by the volume of the suspended layer corresponding to each well inclination angle. The volume of the suspended layer corresponding to each well inclination angle is the difference between the pre-measured annular volume of each well section and the previously calculated volume of the rock cuttings bed of each well section. The volume concentration of rock cuttings in the suspended layer corresponding to each well inclination angle can be obtained by dividing the volume of rock cuttings in the suspended layer corresponding to each well inclination angle by the volume of the suspended layer corresponding to each well inclination angle.

[0082] The specific steps can be as follows:

[0083] (1) Collect the returned cuttings at the wellhead. During the collection process, pay attention to removing the adsorbed drilling fluid and the influence of the weighting materials (such as barite) in the drilling fluid. Then dry and weigh the returned cuttings to obtain the "returned cuttings volume" for the measured drilling time period, and measure the density of the cuttings. The calculation formula is: Where V m,step is the volume of rock cuttings collected during the measurement period, M m,step is the mass of rock cuttings collected in a preset time period, ρ c is the density of the cuttings. m,sum It is the total volume of returned cuttings within a preset time period.

[0084] (2) Calculate the "theoretical amount of rock cuttings" generated at the bottom of the well: Based on the mechanical drilling speed recorded by the logging instrument and the corresponding drilling time period, the "theoretical amount of rock cuttings" generated at the bottom of the well can be calculated. The wellbore expansion rate should also be considered during the calculation, which depends on the information provided by the adjacent well or the experimental well and the type of drill bit. In addition, if the wellbore is unstable, the additional rock cuttings generated by the wellbore collapse and block falling should also be considered. The calculation formula is: where d bit is the drill diameter, V t is the theoretical cuttings volume, and ROP(t) is the mechanical drilling rate.

[0085] (3) The difference between the theoretical amount of rock cuttings and the actual amount of rock cuttings collected is the amount of rock cuttings deposited in the wellbore, which is V re =V t -V m,sum , where V re is the rock cuttings deposited in the wellbore, V t is the theoretical cuttings volume, V m,sum It is the total volume of returned cuttings within a preset time period.

[0086] (4) During the drilling process of the target well, the total volume of the cuttings bed of all well sections of the target well within a preset time period is obtained. A portion of the cuttings remaining in the wellbore forms a cuttings bed. This proportion is related to the drilling parameters and the actual well site. The calculation formula is V re,sb=M sb V re , where V re,sb is the total volume of cuttings in the cuttings bed, M sb is the volume ratio coefficient of cuttings in the cuttings bed, V re It is the rock cuttings deposited in the wellbore.

[0087] (5) The total volume of the rock cuttings particles in the suspension layer of all well sections is calculated using the formula V re,sp =(1-M sb )V re , where V re,sp is the total volume of rock debris particles in the suspension layer, M sb is the volume ratio coefficient of cuttings in the cuttings bed, V re It is the rock cuttings deposited in the wellbore.

[0088] (6) Calculate the total volume of the cuttings bed at the bottom of the well using the formula V re,b =V re,sb / C sb . V re,n is the total volume of the cuttings bed at the bottom of the well, C sb is the solid phase parameter, V re,sb is the total volume of cuttings in the cuttings bed.

[0089] (7) Calculate the cross-sectional area of ​​the cuttings bed at each well inclination angle section of the target well.

[0090] (8) Based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, the current cuttings bed volume corresponding to each well inclination angle section in all well sections is obtained according to the total volume of the cuttings bed.

[0091] The volume of the cuttings bed of each well section is obtained, and then the volume of the cuttings bed of each well section obtained according to the predetermined correspondence between the well inclination angle and the cuttings bed volume is superimposed to obtain the sum of the volumes of the cuttings bed of each well section under the condition of the preset cuttings bed volume of the well section with a well inclination angle of 90 degrees. This sum is compared with the total volume of the cuttings bed obtained previously according to the solid content coefficient. When the error between the two is greater than or equal to 0.001%, the preset cuttings bed volume of the well section with a well inclination angle of 90 degrees is adjusted until the error is less than 0.001%. The volume of the cuttings bed corresponding to each well inclination angle can be obtained based on the adjusted cuttings bed volume of the well section with a well inclination angle of 90 degrees.

[0092] (9) Based on the corresponding relationship between the current cuttings bed height and the cross-sectional area, the current cuttings bed height of the cuttings bed corresponding to each well section with a well inclination angle is determined according to the cross-sectional area.

[0093] (10) Based on the predetermined correspondence between the well inclination angle and the volume of the rock cuttings particles, the current volume of the rock cuttings particles corresponding to the suspension layer of each well section with a well inclination angle is obtained according to the total volume of the rock cuttings particles.

[0094] The volume of rock cuttings in the suspended layer corresponding to each well inclination angle is obtained, and then the volume of rock cuttings in the suspended layer corresponding to each well inclination angle obtained according to the correspondence between the predetermined well inclination angle and the volume of rock cuttings in the suspended layer are superimposed and summed, and then the volume of rock cuttings in the suspended layer after summation is compared with the total volume of rock cuttings in the suspended layer obtained previously according to the proportional coefficient. When the error value between the two is greater than or equal to 0.001%, the preset rock cuttings volume of the well section with a well inclination angle of 90 degrees is adjusted until the error is less than 0.001%. The volume of rock cuttings in the suspended layer corresponding to each well inclination angle can be obtained based on the adjusted rock cuttings volume of the well section with a well inclination angle of 90 degrees.

[0095] (11) Determine the difference between the annular volume and the current cuttings bed volume to obtain the suspended layer volume of the suspended layer in each well section with a well inclination angle; wherein the annular volume is measured in advance.

[0096] (12) According to the volume of the suspended layer and the current volume of the rock cuttings particles, the current volume concentration of the rock cuttings particles corresponding to the suspended layer in each well section with a wellbore inclination angle is determined.

[0097] (13) Based on a preset solid-liquid two-phase flow model, according to the current cuttings bed height and the current cuttings particle volume concentration, the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section are determined.

[0098] In summary, the technical solution provided by the embodiment of the present application has the following advantages: Since cuttings beds are often formed in the middle and large well inclination sections during the drilling process, and the distribution of cuttings beds in the wellbore is unknown, the present application can predict the distribution of cuttings beds in the wellbore during drilling conditions to avoid excessive accumulation of cuttings beds in the wellbore when drilling is stopped and the drilling operation is carried out, which may cause difficulties in drilling and even mechanical drill jams. At the same time, this can be used as a basis to decide whether the drilling operation can be carried out safely. The risk height of the drilling operation can be judged, and then relevant measures can be taken to reduce the height of the cuttings bed based on the predicted distribution of the cuttings bed, so as to achieve the effect of reducing the risk of drill jams.

[0099] A second aspect of an embodiment of the present application provides a processor configured to execute the method for predicting cuttings distribution in a well according to the above-mentioned implementation.

[0100] Figure 2 The schematic diagram of the structure block diagram of the device for predicting the distribution of cuttings in a well in one embodiment of the present application is shown. Figure 2As shown, in a third aspect of an embodiment of the present application, a device 200 for predicting cuttings distribution in a well is provided. The device 200 may include:

[0101] The data acquisition module 201 is used to acquire, during the drilling process of the target well, the total volume of the cuttings bed of all well sections of the target well within a preset time period, the total volume of the cuttings particles in the suspension layer of all well sections, the cross-sectional area of ​​each well section of the target well, and the annular volume of each well section of the well section of the well;

[0102] The cuttings bed volume determination module 202 is used to obtain the current cuttings bed volume corresponding to each well section with a well inclination angle in all well sections according to the total volume of the cuttings bed based on the predetermined correspondence between the well inclination angle and the cuttings bed volume;

[0103] A cuttings bed height determination module 203 is used to determine the current cuttings bed height of the cuttings bed corresponding to each well section with a well inclination angle according to the cross-sectional area based on the corresponding relationship between the current cuttings bed height and the cross-sectional area;

[0104] The cuttings particle volume determination module 204 is used to obtain the current cuttings particle volume corresponding to the suspension layer of each well section with a well inclination angle according to the total volume of the cuttings particles based on the predetermined correspondence between the well inclination angle and the cuttings particle volume;

[0105] The suspended layer volume determination module 205 is used to determine the difference between the annular volume and the current cuttings bed volume to obtain the suspended layer volume of the suspended layer in each well section with a well inclination angle;

[0106] The cuttings particle volume concentration determination module 206 is used to determine the current cuttings particle volume concentration corresponding to the suspension layer of each well section with a wellbore inclination angle according to the suspension layer volume and the current cuttings particle volume;

[0107] The data prediction module 207 is used to determine the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section based on the preset solid-liquid two-phase flow model and the current cuttings bed height and the current cuttings particle volume concentration.

[0108] The above-mentioned device 200 for predicting the distribution of cuttings in a well takes into account the two existing forms of cuttings, namely, the cuttings bed and the suspended layer. Based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, the current cuttings bed volume corresponding to each well inclination angle section in all well sections is obtained; further, the current cuttings bed height of the cuttings bed corresponding to each well inclination angle section is obtained, so that the cuttings bed height of each well section can be accurately calculated, and based on the predetermined correspondence between the well inclination angle and the cuttings particle volume, according to the total volume of the cuttings particles, the cuttings bed height of each well inclination angle section is obtained. The current volume of cuttings particles corresponding to the suspended layer is obtained, and then the current volume concentration of cuttings particles corresponding to the suspended layer of each well section with a wellbore inclination angle is obtained, so that the volume concentration of cuttings particles in each well section can be accurately calculated. The present application uses a preset solid-liquid two-phase flow model, the current volume concentration of cuttings particles and the current height of the cuttings bed to predict the real-time volume concentration of cuttings particles and the real-time height of the cuttings bed, and also improves the accuracy of the prediction results of the cuttings distribution in the well, and uses this as a basis to decide whether it is safe to carry out the drilling operation, thereby improving the safety of production operations.

[0109] In one embodiment, the data acquisition module 201 is also used to: obtain the mass of the returned cuttings collected at the wellhead of the target well within a preset time period and the drilling speed of the drilling equipment; determine the returned cuttings volume of the returned cuttings based on the mass of the returned cuttings and the preset cuttings density; determine the theoretical cuttings volume of the target well based on the drilling speed and the preset time period; determine the difference between the theoretical cuttings volume and the returned cuttings volume to obtain the total cuttings volume of the cuttings of all well sections; determine the product value of the total cuttings volume and the preset proportional coefficient to obtain the cuttings volume in the cuttings bed of all well sections; determine the ratio of the cuttings volume to the preset solid content parameter to obtain the total cuttings bed volume.

[0110] In one embodiment, the data acquisition module 201 is further used to determine the difference between the total volume of rock cuttings and the volume of rock cuttings to obtain the total volume of rock cutting particles.

[0111] In one embodiment, the cuttings bed volume determination module 202 is also used to: based on the predetermined correspondence between the inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, obtain the current cuttings bed volume corresponding to each inclination angle section in all the well sections, including: based on the predetermined correspondence between the inclination angle and the cuttings bed volume, determine the initial cuttings bed volume corresponding to each inclination angle section according to the cuttings bed volume of the preset 90-degree inclination angle section; determine the sum of the initial cuttings bed volumes corresponding to each inclination angle section in all the well sections to obtain the total initial cuttings bed volume; when the difference between the total initial cuttings bed volume and the total cuttings bed volume is greater than or equal to a preset error threshold, adjust the cuttings bed volume of the preset 90-degree inclination angle section until the difference between the sum of the cuttings bed volumes corresponding to each inclination angle section and the total cuttings bed volume is less than the preset error threshold, to obtain the current cuttings bed volume.

[0112] In one embodiment, the cuttings particle volume determination module 204 is also used to: based on the predetermined correspondence between the well inclination angle and the cuttings particle volume, according to the total volume of the cuttings particles, obtain the current cuttings particle volume corresponding to the suspension layer of each well inclination angle section, including: based on the predetermined correspondence between the well inclination angle and the cuttings particle volume, determine the initial cuttings particle volume corresponding to each well inclination angle section according to the cuttings particle volume of the preset 90-degree well inclination angle section; determine the sum of the initial cuttings particle volumes corresponding to each well inclination angle section in all the well sections to obtain the total initial cuttings particle volume; when the difference between the initial total cuttings particle volume and the total cuttings particle volume is greater than or equal to the preset error threshold, adjust the cuttings particle volume of the preset 90-degree well inclination angle section until the difference between the sum of the initial cuttings particle volumes corresponding to each well inclination angle section and the total cuttings particle volume is less than the preset error threshold, to obtain the current cuttings particle volume.

[0113] In one embodiment, the cuttings particle volume concentration determination module 206 is also used to determine the current cuttings particle volume concentration corresponding to the suspended layer of each well section with a wellbore inclination angle according to the suspended layer volume and the current cuttings particle volume, including: determining the ratio of the current cuttings particle volume to the suspended layer volume to obtain the cuttings particle volume concentration.

[0114] In one embodiment, the data prediction module 207 is also used to: based on a preset solid-liquid two-phase flow model, according to the current cuttings bed height and the current volume concentration of cuttings particles, determine the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section, including: obtaining drilling operating parameters; based on a preset solid-liquid two-phase flow model, according to the drilling operating parameters, the current cuttings bed height and the current volume concentration of cuttings particles, determine the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section.

[0115] A fourth aspect of an embodiment of the present application provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute the method for predicting the distribution of cuttings in a well according to the above-mentioned embodiment.

[0116] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0117] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A method for predicting cuttings distribution in a well, characterized in that: The method comprises: During the drilling process of the target well, the total volume of the cuttings bed of all sections of the target well within a preset time period, the total volume of the cuttings particles in the suspension layer of all sections, the cross-sectional area of ​​the cuttings bed of each section with a well deviation angle of the target well, and the annular volume of each section with a well deviation angle are obtained; Based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, according to the total volume of the cuttings bed, obtaining the current cuttings bed volume corresponding to each well inclination angle well section in all the well sections; Based on the corresponding relationship between the current cuttings bed height and the cross-sectional area, determining the current cuttings bed height of the cuttings bed corresponding to each well section with the well inclination angle according to the cross-sectional area; Based on the predetermined correspondence between the well inclination angle and the volume of rock cuttings particles, according to the total volume of the rock cuttings particles, the current volume of the rock cuttings particles corresponding to the suspension layer of each well section with the well inclination angle is obtained; Determine the difference between the annular space volume and the current cuttings bed volume to obtain the suspended layer volume of the suspended layer in each well section with the well inclination angle; Determine the current volume concentration of rock cuttings particles corresponding to the suspension layer of each well section with a wellbore inclination angle according to the volume of the suspension layer and the current volume of rock cuttings particles; Based on the preset solid-liquid two-phase flow model, according to the current cuttings bed height and the current cuttings particle volume concentration, the predicted cuttings bed height corresponding to each well inclination angle section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination angle section are determined.

2. The method according to claim 1, characterized in that The acquisition of the total volume of the cuttings bed includes: Obtaining the quality of the returned rock cuttings collected at the wellhead of the target well within the preset time period and the drilling speed of the drilling equipment; Determining the returned rock cuttings volume of the returned rock cuttings according to the returned rock cuttings mass and a preset rock cuttings density; Determining a theoretical cuttings volume of the target well according to the drilling speed and a preset time period; Determine the difference between the theoretical cuttings volume and the returned cuttings volume to obtain the total cuttings volume of all well sections; Determine the product value of the total volume of cuttings and a preset proportionality coefficient to obtain the volume of cuttings in the cuttings bed of all well sections; The ratio of the rock cuttings volume to a preset solid content parameter is determined to obtain the total volume of the rock cuttings bed.

3. The method according to claim 2, characterized in that The acquisition of the total volume of rock cuttings particles includes: The difference between the total volume of the rock cuttings and the volume of the rock cuttings is determined to obtain the total volume of the rock cutting particles.

4. The method according to claim 1, characterized in that: The method of obtaining the current cuttings bed volume corresponding to each well section with a well inclination angle in all well sections based on the predetermined correspondence between the well inclination angle and the cuttings bed volume and the total cuttings bed volume comprises: Based on the predetermined correspondence between the well inclination angle and the cuttings bed volume, the initial cuttings bed volume corresponding to each well inclination angle section is determined according to the cuttings bed volume of the well section with a preset well inclination angle of 90 degrees; Determine the sum of the initial cuttings bed volumes corresponding to each well section with a well inclination angle in all the well sections to obtain the total volume of the initial cuttings bed; When the difference between the initial total volume of the cuttings bed and the total volume of the cuttings bed is greater than or equal to a preset error threshold, the cuttings bed volume of the preset 90-degree inclination angle section is adjusted until the difference between the sum of the cuttings bed volumes corresponding to each of the inclination angle sections and the total volume of the cuttings bed is less than the preset error threshold, so as to obtain the current cuttings bed volume.

5. The method according to claim 1, characterized in that The method of obtaining the current volume of rock cuttings particles corresponding to the suspension layer of each well section with a well inclination angle based on the predetermined correspondence between the well inclination angle and the volume of rock cuttings particles according to the total volume of the rock cuttings particles includes: Based on the predetermined correspondence between the well inclination angle and the volume of the rock cutting particles, the initial rock cutting particle volume corresponding to each well inclination angle section is determined according to the rock cutting particle volume of the well inclination angle section preset at 90 degrees; Determine the sum of the initial rock cutting particle volumes corresponding to each well inclination angle well section in all the well sections to obtain the total volume of the initial rock cutting particles; When the difference between the initial total volume of rock cuttings particles and the total volume of rock cuttings particles is greater than or equal to a preset error threshold, the volume of rock cuttings particles in the preset 90-degree well inclination angle well section is adjusted until the difference between the sum of the initial rock cuttings particle volumes corresponding to each well inclination angle well section and the total volume of rock cuttings particles is less than the preset error threshold, so as to obtain the current rock cuttings particle volume.

6. The method according to claim 1, characterized in that The step of determining the current rock cutting particle volume concentration corresponding to the suspended layer of each well section with a well inclination angle according to the suspended layer volume and the current rock cutting particle volume includes: The ratio of the current rock cutting particle volume to the suspension layer volume is determined to obtain the rock cutting particle volume concentration.

7. The method according to claim 1, characterized in that The step of determining the predicted cuttings bed height corresponding to each well inclination angle section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination angle section based on the preset solid-liquid two-phase flow model and the current cuttings bed height and the current cuttings particle volume concentration comprises: Obtain drilling condition parameters; Based on a preset solid-liquid two-phase flow model, according to the drilling operating parameters, the current cuttings bed height and the current cuttings particle volume concentration, the predicted cuttings bed height corresponding to each well inclination section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination section are determined.

8. A processor, characterized in that: The method is configured to execute the method for predicting cuttings distribution in a well according to any one of claims 1 to 7.

9. A device for predicting the distribution of cuttings in a well, characterized in that: The device comprises: A data acquisition module, used for acquiring, during the drilling process of the target well, the total volume of the cuttings bed of all well sections of the target well within a preset time period, the total volume of the cuttings particles in the suspension layer of all well sections, the cross-sectional area of ​​the cuttings bed of each well section with a well inclination angle of the target well, and the annular volume of each well section with a well inclination angle; A cuttings bed volume determination module, for obtaining the current cuttings bed volume corresponding to each well section with a well inclination angle in all the well sections according to the total volume of the cuttings bed based on the predetermined correspondence between the well inclination angle and the cuttings bed volume; A cuttings bed height determination module, configured to determine the current cuttings bed height of the cuttings bed corresponding to each well section with a well inclination angle according to the cross-sectional area based on the corresponding relationship between the current cuttings bed height and the cross-sectional area; A cuttings particle volume determination module, for obtaining the current cuttings particle volume corresponding to the suspension layer of each well section with the well inclination angle according to the total volume of the cuttings particles based on the predetermined correspondence between the well inclination angle and the cuttings particle volume; A suspension layer volume determination module, used for determining the difference between the annular space volume and the current cuttings bed volume, so as to obtain the suspension layer volume of the suspension layer of each well section with a well inclination angle; A cuttings particle volume concentration determination module, used to determine the current cuttings particle volume concentration corresponding to the suspension layer of each well section with a wellbore inclination angle according to the suspension layer volume and the current cuttings particle volume; The data prediction module is used to determine the predicted cuttings bed height corresponding to each well inclination angle section of the target well and the predicted cuttings particle volume concentration corresponding to the suspended layer of each well inclination angle section based on a preset solid-liquid two-phase flow model and according to the current cuttings bed height and the current cuttings particle volume concentration.

10. A machine-readable storage medium, characterized in that: The machine-readable storage medium stores instructions for causing a machine to execute the method for predicting cuttings distribution in a well according to any one of claims 1 to 8.

Images