Method, device and equipment for monitoring drilling operations based on friction coefficient

Abstract

The embodiments of this specification disclose a method, device and equipment for monitoring drilling operations based on friction coefficient. The influence of time effect is considered in the inversion process of friction coefficient, and the weight coefficient related to the well depth is introduced. The weighted average error of the calculated value of the hook load or the turntable torque is used as the objective function, which can realize the dynamic inversion of the friction coefficient during drilling. According to the inversion result of the friction coefficient, the changes in the wellbore cleaning condition, formation properties, wellbore tortuosity, etc. are judged, and the hook load and turntable torque are predicted, realizing the real-time monitoring of the wellbore conditions and operating conditions during drilling. The calculation accuracy of the friction coefficient is improved, and then the accuracy of monitoring the drilling operation conditions and wellbore conditions is improved, and the safety of drilling operations is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas extraction, and in particular to a method, device and equipment for monitoring drilling operations based on friction coefficient. Background Art

[0002] The accurate calculation of the friction torque of downhole tubing is of great significance in drilling optimization design and safety control. The evaluation of drilling rig adaptability, wellbore trajectory optimization design, overall force and optimization design of drill string, feasibility analysis of completion string running, downhole accident prediction and prevention, and recommendation and adjustment of drilling and completion measures are all related to the friction torque of downhole tubing. In the calculation process of the friction torque of downhole tubing, the friction coefficient is very critical and is generally determined by the inversion method. Therefore, based on the friction coefficient, parameters such as friction torque in the drilling process can be monitored to ensure the safety of drilling operations.

[0003] Traditional friction coefficient inversion methods usually use one friction coefficient to describe the entire wellbore condition, or divide the wellbore into a casing section and an open hole section and use two friction coefficients to describe the entire wellbore condition. However, the friction coefficient depends on many influencing factors, such as formation properties, drilling fluid properties, wellbore tortuosity, wellbore cleaning conditions, etc., and is a comprehensive reflection of wellbore conditions. In addition, wellbore conditions are constantly changing during actual drilling, and it is inaccurate to use a fixed value to calculate the friction coefficient. If the friction coefficient is not calculated accurately, it will affect the accuracy of parameters such as friction torque, and further affect the safety of drilling operations.

[0004] Therefore, how to provide a solution to accurately calculate the friction coefficient during the drilling operation and then conduct safety monitoring of the drilling operation is a technical problem that urgently needs to be solved in this field. Summary of the invention

[0005] The purpose of the embodiments of this specification is to provide a method, device and equipment for monitoring drilling operations based on friction coefficient, thereby improving the accuracy of friction coefficient calculation and the safety of drilling operations.

[0006] On the one hand, an embodiment of this specification provides a method for monitoring drilling operations based on a friction coefficient, the method comprising:

[0007] Calculate the hook load and rotary table torque at different well depths based on the friction coefficient;

[0008] Calculate the weight value of the friction coefficient of each data point according to the distance between each data point and the bottom of the wellbore;

[0009] Calculate the weighted average of the calculation errors of the hook load or the rotary table torque at different well depths based on the weight values ​​of the friction coefficient corresponding to each data point, and use the weighted average as the objective function;

[0010] Solving the objective function to obtain a target friction coefficient when the objective function takes a minimum value;

[0011] The wellbore conditions and operating conditions during the drilling operation are monitored based on the target friction coefficient.

[0012] Further, the friction coefficient weight value of each data point is calculated according to the distance of each data point from the bottom of the wellbore, including using the following formula to calculate the friction coefficient weight value:

[0013]

[0014] Among them, ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, d i represents the distance from the i-th data point to the bottom of the wellbore, d i It is the serial number of each data point sorted from the bottom of the well upward, where each data point is sorted from small to large according to the well depth, p represents the power index, p≥0.

[0015] Furthermore, the power index is at least one of 0, 1, and 2.

[0016] Furthermore, the friction coefficient includes the friction coefficient of the casing section and the friction coefficient of the open hole section.

[0017] Furthermore, the weighted average of the calculation errors of the hook load or the rotary table torque at different well depths is calculated based on the friction coefficient weight values ​​corresponding to each data point, including:

[0018] For the data points of the tubing sliding operation, the weighted average value of the hook load at the corresponding well depth is calculated based on the weight value of the friction coefficient corresponding to each data point;

[0019] For the data points of the pipe string rotation operation, the weighted average value of the rotary table torque corresponding to the well depth is calculated based on the friction coefficient weight value corresponding to each data point;

[0020] The sum of the weighted average value of the hook load and the weighted average value of the turntable torque is taken as the weighted average value.

[0021] Furthermore, the objective function is calculated using the following formula:

[0022]

[0023] Wherein, Err represents the objective function, c1 and c2 represent the coefficient values ​​of two different working conditions, namely, string sliding and string rotation. When the string slides, c1=1, c2=0, and when the string rotates, c1=0, c2=1. ρi represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, hk i represents the hook load measured at the well depth corresponding to the i-th data point, tor i represents the rotary table torque measured at the well depth corresponding to the i-th data point, hk cali represents the hook load calculated at the well depth corresponding to the ith data point, tor cali It represents the rotary table torque calculated at the well depth corresponding to the ith data point.

[0024] Furthermore, the monitoring of the borehole conditions and the operating conditions during the drilling operation based on the target friction coefficient includes:

[0025] As the drilling depth increases, the target friction coefficient corresponding to different well depths is obtained in turn;

[0026] Monitor the wellbore conditions at different well depths based on the changing trend of the target friction coefficient at different well depths;

[0027] The hook load and turntable torque at different well depths are predicted based on the target friction coefficient at different well depths. Whether the drilling operation is overloaded is determined based on the calculated hook load and turntable torque, and the operating conditions during the drilling process are monitored.

[0028] On the other hand, the present specification provides a device for monitoring drilling operations based on friction coefficient, the device comprising:

[0029] Parameter calculation module, used to calculate the hook load and rotary table torque at different well depths based on the friction coefficient;

[0030] The weight configuration module is used to calculate the weight value of the friction coefficient of each data point according to the distance of each data point from the bottom of the wellbore;

[0031] An objective function calculation module is used to calculate the weighted average value of the calculation error of the hook load or the rotary table torque at different well depths based on the weight value of the friction coefficient corresponding to each data point, and use the weighted average value as the objective function;

[0032] A friction coefficient solving module, used for solving the objective function to obtain a target friction coefficient when the objective function takes a minimum value;

[0033] The monitoring module is used to monitor the wellbore conditions and operating conditions during the drilling operation based on the target friction coefficient.

[0034] Furthermore, the weight configuration module is specifically used to calculate the friction coefficient weight value using the following formula:

[0035]

[0036] Among them, ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, d i represents the distance from the i-th data point to the bottom of the wellbore, d i It is the serial number of each data point sorted from the bottom of the well upward, where each data point is sorted from small to large according to the well depth, p represents the power index, p≥0.

[0037] On the other hand, an embodiment of the present specification provides a device for monitoring drilling operations based on friction coefficient, the device includes at least one processor and a memory for storing processor executable instructions, and when the instructions are executed by the processor, the method for monitoring drilling operations based on friction coefficient is implemented.

[0038] The method, device and equipment for monitoring drilling operations based on friction coefficient provided in this specification considers the influence of time effect in the inversion process of friction coefficient, introduces weight coefficient related to well depth, and takes the weighted average error of the calculated value of hook load or turntable torque as the objective function, which can realize dynamic inversion of friction coefficient during drilling, and judge the changes of wellbore cleaning, formation properties, wellbore tortuosity, etc. according to the inversion result of friction coefficient, and predict the hook load and turntable torque, so as to realize real-time monitoring of wellbore conditions and operating conditions during drilling. The calculation accuracy of friction coefficient is improved, and then the monitoring accuracy of drilling operating conditions and wellbore conditions is improved, and the safety of drilling operations is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0040] Figure 1 It is a flow chart of an embodiment of a method for monitoring drilling operations based on friction coefficient provided in an embodiment of this specification;

[0041] Figure 2 is a schematic diagram of the distribution of friction coefficient weight values ​​corresponding to individual data points when the power exponent takes different values ​​in one embodiment of this specification;

[0042] Figure 3(a)-Figure 3(c) is a schematic diagram showing the variation of the friction coefficient obtained by inversion during the drilling of the wellbore of Well X in the embodiment of this specification with the well depth;

[0043] Figure 4 is a schematic diagram of a process flow of dynamic inversion of friction coefficient in one embodiment of the present specification;

[0044] Figure 5 is a schematic diagram of the monitoring result of the turntable torque in one embodiment of this specification;

[0045] Figure 6 is a schematic diagram of the structure of a device for monitoring drilling operations based on friction coefficient in one embodiment of the present specification;

[0046] Figure 7 This is a hardware structure block diagram of a server for monitoring drilling operations based on friction coefficient in one embodiment of this specification. DETAILED DESCRIPTION

[0047] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this specification.

[0048] During the actual drilling process, the borehole conditions are constantly changing, resulting in the friction coefficient being a variable. The embodiment of this specification establishes a dynamic inversion method for the friction coefficient during the drilling process. Based on the friction coefficient obtained by inversion, the changes in the borehole conditions and the changes in the drilling operation conditions can be monitored in real time.

[0049] Figure 1 It is a flow chart of a method embodiment for monitoring drilling operations based on friction coefficient provided in an embodiment of this specification. Although this specification provides method operation steps or device structures as shown in the following embodiments or drawings, more or fewer operation steps or module units may be included in the method or device based on routine or no creative labor. In the steps or structures where there is no necessary causal relationship logically, the execution order of these steps or the module structure of the device is not limited to the execution order or module structure shown in the embodiments or drawings of this specification. When the method or module structure is applied in an actual device, server or terminal product, it can be executed sequentially or in parallel according to the method or module structure shown in the embodiment or drawings (for example, a parallel processor or multi-threaded processing environment, or even a distributed processing, server cluster implementation environment).

[0050] A specific implementation example is Figure 1As shown, in one embodiment of the method for monitoring drilling operations based on friction coefficient provided in this specification, the method can be applied to devices such as servers, computers, smart phones, and tablet computers, and the method may include the following steps:

[0051] Step 102: Calculate the hook load and rotary table torque at different well depths based on the friction coefficient.

[0052] In the specific implementation process, the friction coefficient can be understood as a coefficient related to the roughness of the wall of the well or pipeline and the air density. The hook load refers to the axial force borne by the hook. It is one of the important basic data for drilling rig selection and equipment matching, and it is also one of the important bases for drilling construction safety assessment. Therefore, it is very important to effectively predict the hook load during drilling. From the process of drilling, completion and handling of complex accidents, the load borne by the hook includes the deadweight of the drilling rig lifting system and the tubing, the buoyancy of the drilling fluid, the bending force of the curved well section, the friction of the well wall, and the impact force when encountering resistance and jamming. The turntable torque is one of the important parameters obtained by the drilling rig rotation system. The calculation process of the hook load and the turntable torque The friction coefficient is an important parameter. There are many ways to calculate the hook load and the turntable torque, which can be selected according to actual needs. The embodiments of this specification do not make specific limitations.

[0053] In some embodiments of this specification, the downhole tubular string friction torque calculation model may include a soft rod model and a rigid rod model. The soft rod model regards the tubular string as a "soft rope" that cannot withstand bending moment. The calculation formula is as follows:

[0054]

[0055] Where D t is the outer diameter of the pipe column joint, in meters; F e is the axial force, the unit is N; M t is the torque, the unit is N·m; w bp is the buoyancy weight of the pipe per unit length, in N·m; w c is the contact force per unit length of the pipe, in N·m; μ d is the axial component of the friction coefficient μ, which is positive when lowering and negative when lifting; μ t is the circumferential component of the friction coefficient μ; α is the well inclination angle, the unit is °.

[0056] The rigid rod model further considers the influence of string stiffness and wellbore bending on the basis of the soft rod model. Its calculation formula is:

[0057]

[0058] Where E is the elastic modulus, the unit is N / m 2; I is the moment of inertia, the unit is m 4 ; k is the wellbore curvature, unit is m -1 ; r o is the outer diameter of the pipe column, in m; t z is the component of the unit tangent vector of the pipe string microelement in the vertical direction; θ is the angle between the contact direction line between the pipe string and the well wall and the main normal direction. The meanings of other parameters are the same as those in formula (1) and will not be repeated here.

[0059] Rewrite formula (1) or formula (2) into differential format, and then perform iterative calculation to obtain the axial force F at the ground: e is the hook load, the torque M at the ground t Of course, according to the actual situation, other methods can also be used to calculate the hook load and the turntable torque, which are not specifically limited in the embodiments of this specification.

[0060] In addition, in some embodiments of this specification, the friction coefficient includes the friction coefficient of the casing section and the friction coefficient of the open hole section. That is to say, two friction coefficients can be used in the embodiments of this specification. The friction coefficient depends on many influencing factors, such as formation properties, drilling fluid properties, wellbore tortuosity, wellbore cleaning conditions, etc., and is a comprehensive reflection of wellbore conditions. For conventional directional wells, a single friction coefficient can meet the engineering accuracy requirements, but for large displacement wells or long horizontal wells, using two friction coefficients is more in line with the operating conditions and has higher accuracy. The μ in the above formulas (1) and (2) is d , μ t There can be two, the axial component and the circumferential component of the friction coefficient of the casing section and the axial component and the circumferential component of the friction coefficient of the open hole section.

[0061] Step 104: Calculate the friction coefficient weight value of each data point according to the distance between each data point and the bottom of the wellbore.

[0062] In the specific implementation process, the friction coefficient depends on many factors such as formation properties, drilling fluid properties, wellbore tortuosity, wellbore cleaning conditions, etc., and is a comprehensive reflection of wellbore conditions. Wellbore conditions are constantly changing during actual drilling. In the embodiments of this specification, the friction coefficient is used as a variable, and a friction coefficient weight value is introduced to add weight to the friction coefficient. As the well depth changes, the weight of the friction coefficient is also constantly changing. In the embodiments of this specification, the friction coefficient weight value corresponding to each data point can be calculated based on the distance from each data point to the bottom of the wellbore. Generally, the closer the data point is to the bottom of the wellbore, the larger the corresponding friction coefficient weight value is. The larger the friction coefficient weight value is, the greater the impact on the subsequent objective function is. Among them, the data point refers to the measurement point for measuring the hook load and the turntable torque.

[0063] In some embodiments of this specification, the friction coefficient weight value of each data point is calculated according to the distance of each data point from the bottom of the wellbore, including using the following formula to calculate the friction coefficient weight value:

[0064]

[0065] Among them, ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, d i represents the distance from the i-th data point to the bottom of the wellbore, d i It is the serial number of each data point sorted from the bottom of the well upward, where each data point is sorted from small to large according to the well depth, p represents the power index, p≥0.

[0066] In the specific implementation process, i Indicates the distance of each measuring point from the bottom of the wellbore, mainly used to represent the timeliness of different measuring points. If the measured values ​​of n hook loads and rotary table torques are sorted from small to large by well depth (the values ​​of hook loads and rotary table torques will be continuously recorded as the well depth increases during the actual drilling process. Generally speaking, hook loads and rotary table torques are sorted from small to large by well depth), that is, each data point is sorted from small to large by well depth, then d i =n+1-i. For example, if n=10, that is, there are 10 data points, and the 10 data points are sorted in order from the depth of the well, that is, they are sorted from 1 to 10 starting from the wellbore. When i=1, d1=n+1-i=10+1-1=10, that is, the distance from the first data point to the bottom of the wellbore is 10, and the sequence number of the first data point sorted from the bottom of the wellbore upward is also 10. Therefore, d i is the sequence number of each data point sorted from the bottom of the well upward, then, d i =1 is actually the 10th data point, indicating the measuring point with the largest well depth.

[0067] It can be seen from the above formula (3) that, in general, d i The larger the value, that is, the farther the distance from the bottom of the wellbore, the smaller the weight value of the friction coefficient. Of course, the size of the friction coefficient weight value is also related to the power exponent p, which can indicate that the friction coefficient weight value increases with d i The speed of decrease with the increase of d can generally be determined according to actual needs. When p = 0, it means that the weights of each measuring point are the same, that is, the traditional friction coefficient inversion method; when p> 0, it means that the weights of each measuring point are the same as d i It is inversely proportional to p, that is, the closer the measuring point is to the current well depth, the greater its weight is. It should be noted that when the power exponent is too large, the inversion value of the friction coefficient depends more on the current measuring point, and the error of the inversion result of the friction coefficient is relatively large.

[0068] In some embodiments of the present specification, the power index p can be at least one of 0, 1, and 2. After many experiments, when p is 0, 1, and 2, it can respectively represent the working conditions of different drilling conditions, and can accurately invert and calculate the friction coefficient, which is suitable for drilling operations under different conditions. Figure 2 : is a schematic diagram of the distribution of friction coefficient weight values ​​corresponding to data points when the power index takes different values ​​in one embodiment of this specification, Figure 2 The horizontal axis represents the distance d between the data point and the bottom of the wellbore. i The smaller the value, the deeper the well is, that is, the closer it is to the bottom of the wellbore. Figure 2 As shown in the figure, when p is 0, the friction coefficient weight value is a fixed value, and when p is 1 or 2, the friction coefficient weight value gradually decreases with the decrease of the well depth, and the decrease rate of the friction coefficient weight value when p is 2 is greater than that when p is 1. The power exponents of 0, 1, and 2 can represent the wellbore conditions in different time ranges respectively, and the appropriate value can be selected according to the actual situation to more accurately calculate the friction coefficient, and then accurately monitor the drilling operation.

[0069] Step 106: Calculate the weighted average of the calculation errors of the hook load or the rotary table torque at different well depths based on the weight values ​​of the friction coefficient corresponding to each data point, and use the weighted average as the objective function.

[0070] In the specific implementation process, in the embodiments of this specification, the measured values ​​of the hook load or turntable torque corresponding to each data point can be measured first, and then the hook load or turntable torque calculated based on the friction coefficient of each data point can be weighted averaged with the corresponding measured value combined with the corresponding friction coefficient weight value to obtain the weighted average of the calculation errors of the hook load or turntable torque at different well depths, that is, the objective function.

[0071] For example, taking the weighted average value of the calculation error of the hook load at different well depths as an example, assuming that there are 10 data points, the measured values ​​of the hook load at each data point are F1, F2, ..., F10, the calculated values ​​of the hook load at each data point are f1, f2, ..., f10, and the weight values ​​of the friction coefficient weight values ​​corresponding to each data point are ρ1, ρ2, ..., ρ 10 The weighted average value of the calculation error of the hook load at different well depths is: (ρ1×|F1-f1|+ρ2×|F2-f2|+…+ρ 10 ×|F10-f10|) / 10.

[0072] It can be seen that in the embodiment of this specification, the closer the measuring point is to the current well depth, the greater the weight in the objective function, and the farther away, the smaller the weight is, so as to more accurately predict the current wellbore condition.

[0073] Of course, other methods can be used to calculate the objective function according to actual needs. In some embodiments of this specification, the weighted average of the calculation errors of the hook loads at different well depths or the weighted average of the calculation errors of the turntable torques at different well depths can be selected as the objective function. The specific method can be selected based on actual conditions.

[0074] In some embodiments of this specification, the weighted average value of the calculation error of the hook load or the rotary table torque at different well depths is calculated based on the friction coefficient weight value corresponding to each data point, including:

[0075] For the data points of the tubing sliding operation, the weighted average value of the hook load at the corresponding well depth is calculated based on the weight value of the friction coefficient corresponding to each data point;

[0076] For the data points of the pipe string rotation operation, the weighted average value of the rotary table torque corresponding to the well depth is calculated based on the friction coefficient weight value corresponding to each data point;

[0077] The sum of the weighted average value of the hook load and the weighted average value of the turntable torque is taken as the weighted average value.

[0078] In the specific implementation process, generally, when the pipe string slides, the friction coefficient only affects the calculated value of the hook load. Therefore, for the data points of pipe string sliding, the weighted average value of the hook load corresponding to the well depth can be calculated. When the pipe string rotates, the friction coefficient mainly affects the calculated value of the turntable torque, and the influence on the hook load can be ignored. Therefore, for the data points of pipe string rotation, the weighted average value of the turntable torque corresponding to the well depth can be calculated. Then, the two weighted average values ​​are superimposed to obtain the final weighted average value, which is the objective function.

[0079] Based on different working conditions, the hook load or turntable torque is selected for calculation, so that the calculation results are more in line with the actual operating conditions, thereby improving the accuracy of friction coefficient inversion, and further improving the accuracy of drilling operation monitoring and the safety of drilling operations.

[0080] In some embodiments of this specification, the objective function is calculated using the following formula:

[0081]

[0082] Wherein, Err represents the objective function, c1 and c2 represent the coefficient values ​​of two different working conditions, namely, string sliding and string rotation. When the string slides, c1=1, c2=0, and when the string rotates, c1=0, c2=1. ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, hk irepresents the hook load measured at the well depth corresponding to the i-th data point, tor i represents the rotary table torque measured at the well depth corresponding to the i-th data point, hk cali represents the hook load calculated at the well depth corresponding to the ith data point, tor cali It represents the rotary table torque calculated at the well depth corresponding to the ith data point.

[0083] In the specific implementation process, the weighted average value of the calculation error of the hook load or the turntable torque at different well depths can be calculated using the above formula (4). Referring to formula (4), it can be seen that the calculation of the objective function is related to the weight value of the friction coefficient of the data points at each well depth, and the closer the measuring point is to the current well depth, the greater the weight in the objective function, and the farther away, the smaller the weight.

[0084] Step 108: Solve the objective function to obtain the target friction coefficient when the objective function takes the minimum value.

[0085] In the specific implementation process, after obtaining the objective function, the objective function can be optimized and solved. Specifically, the calculated value of the hook load or turntable torque in the objective function can be substituted into the above objective function, such as: the hook load or turntable torque is calculated by using formula (1) or formula (2) in the above embodiment, and substituted into the objective function of the above formula (4), and the friction coefficient when the objective function takes the minimum value is the target friction coefficient. The ultimate optimization goal is to find the appropriate casing section friction coefficient μ1 and open hole section friction coefficient μ2, so that the calculation error of the hook load or turntable torque calculated by the pipe string friction torque model (formula (1) or formula (2)) takes the minimum value under the corresponding weight coefficient, that is, the objective function reaches the minimum Err.

[0086] In specific calculations, the corresponding friction coefficient can be obtained by setting the power exponent p to different values. Figure 3(a)-Figure 3(c) It is a schematic diagram of the variation of the friction coefficient obtained by inversion with the well depth during the drilling of the well X in the embodiment of this specification. As shown in FIG3(a), when p=0, the friction coefficient μ1 of the casing section and the friction coefficient μ2 of the open hole section obtained by inversion are relatively stable and do not change greatly with the well depth. As shown in FIG3(b), when p=1, the friction coefficient μ1 of the casing section and the friction coefficient μ2 of the open hole section obtained by inversion will change with the well depth, especially μ2. As shown in FIG3(c), when p=2, the friction coefficient of the casing section and the friction coefficient of the open hole section obtained by inversion change significantly with the well depth.

[0087] Figure 4 FIG. 1 is a schematic diagram of a process flow of dynamic inversion of friction coefficient in an embodiment of the present specification. Figure 4As shown, the measured hook load, rotary table torque, hook load and friction coefficient calculated using the friction coefficient, drilling parameters, trajectory parameters, well depth structure, etc. can be input into the friction coefficient dynamic inversion model, i.e., the objective function in the above embodiment, and the calculation formula of the friction coefficient weight value, that is, the casing section friction coefficient μ1 and the open hole section friction coefficient μ2 can be obtained. Figure 4 As shown in the figure, the power exponent can be set to different values ​​during the inversion process to obtain different friction coefficients. As the well depth increases, that is, the drilling operation continues, the bottom of the wellbore is constantly changing, so the weight value of the friction coefficient corresponding to each data point is also constantly changing. During the drilling process, the data can be updated with the drilling operation to recalculate the friction coefficient at different well depths.

[0088] Step 110: Monitor the wellbore conditions and operating conditions during the drilling operation based on the target friction coefficient.

[0089] In a specific implementation process, after the target friction coefficient in the drilling process is inverted using the method of the embodiment of this specification, the wellbore conditions and operating conditions can be monitored based on the distribution of the friction coefficient. The larger the value of the power index, the more dependent the inversion of the friction coefficient is on the current measuring point, and the more representative the inversion result of the friction coefficient is of the current wellbore conditions. In the embodiment of this specification, the power index takes 0, 1, and 2, respectively, and the inversion results of the friction coefficient represent the average wellbore conditions, the medium-term wellbore conditions, and the short-term wellbore conditions, respectively, to monitor the wellbore conditions within different time ranges and provide a basis for real-time decision-making of control measures. As shown in Figure 3(a), when p=0, the inverted friction coefficient μ1 of the casing section and the friction coefficient μ2 of the open hole section are very stable, indicating that the average wellbore conditions of Well X do not change much during the drilling of the wellbore, such as Figure 3(b)-Figure 3(c) As shown in the figure, when p = 1 or when p = 2, the friction coefficient μ1 of the casing section obtained by inversion is relatively stable, while the friction coefficient μ2 of the open hole section fluctuates violently. This shows that during the drilling process, the wellbore conditions of the casing section do not change much, but with the increase of well depth, there must be differences in the wellbore cleaning conditions, formation properties, and wellbore tortuosity of the open hole section. In addition, the turntable torque, hook load, etc. can also be predicted based on the friction coefficient obtained by inversion, such as: using the friction coefficient obtained by inversion to calculate the turntable torque and hook load, and judging whether the current drilling operation is overloaded or in a safe operating environment based on the calculated turntable torque and hook load.

[0090] Based on this, in one embodiment of this specification, monitoring the wellbore conditions and operating conditions during the drilling operation based on the target friction coefficient includes:

[0091] As the drilling depth increases, the target friction coefficient corresponding to different well depths is obtained in turn;

[0092] Monitor the wellbore conditions at different well depths based on the changing trend of the target friction coefficient at different well depths;

[0093] The hook load and turntable torque at different well depths are predicted based on the target friction coefficient at different well depths. Whether the drilling operation is overloaded is determined based on the calculated hook load and turntable torque, and the operating conditions during the drilling process are monitored.

[0094] In the specific implementation process, the dynamic inversion method of the friction coefficient provided in the embodiment of this specification can be used to calculate the continuous deepening of the drilling depth during the drilling process and obtain the target friction coefficient at different well depths. Based on the change trend of the calculated friction coefficient, the hook load and turntable torque at different well depths and the corresponding wellbore conditions are predicted. Based on the wellbore conditions and the predicted hook load and turntable torque, it is determined whether the drilling operation is overloaded, and the operating conditions during the drilling process are monitored. The larger the power exponent in the friction coefficient weight value, when the prediction section length is small, the closer the change trend of the calculated value of the hook load and turntable torque is to the change trend of the recorded value of the hook load and turntable torque near the prediction point. Therefore, based on the dynamic inversion result of the friction coefficient, the hook load and turntable torque can be accurately predicted, thereby improving the accuracy of drilling operation safety monitoring and improving the safety of drilling operations.

[0095] Specifically, the wellbore conditions can be monitored based on the changing trend of the friction coefficient with the well depth. After the weight coefficient is introduced, the larger the power exponent value is, the more the inversion value of the friction coefficient can represent the current wellbore conditions, thereby realizing accurate monitoring of the current wellbore conditions. Figure 5 Schematic diagram of the monitoring result of the turntable torque in one embodiment of this specification. Figure 5 As shown in the figure, when the prediction segment length is small, the larger the power index is, the closer the prediction result of the turntable torque is to the measured value. Similarly, the prediction result of the hook load is also related to the power index. In the traditional friction coefficient inversion method, the influence of all measurement points in the historical data is considered to be the same. Then, the hook load or turntable torque calculated based on the friction coefficient inversion value has a high overall calculation accuracy compared with the measured value, but the calculation accuracy in the local area is difficult to guarantee. Therefore, the prediction accuracy of the hook load or turntable torque cannot be guaranteed.

[0096] After the weight coefficient, i.e., the weight value of the friction coefficient, is introduced, the larger the power exponent is, the more the friction coefficient inversion value can represent the current wellbore condition. After the friction coefficient is introduced into the friction torque model, the change law of the predicted value of the rotary table torque is closer to the change law of the measured value of the rotary table torque near the well depth where the prediction is started. In this way, the prediction accuracy of the hook load or rotary table torque is relatively high when the prediction section length is small.

[0097] The method for monitoring drilling operations based on friction coefficient provided in this specification takes into account the influence of time effect in the inversion process of friction coefficient, introduces weight coefficient related to well depth, and takes the weighted average error of the calculated value of hook load or turntable torque as the objective function, which can realize dynamic inversion of friction coefficient during drilling. According to the inversion result of friction coefficient, the changes of wellbore cleaning condition, formation properties, wellbore tortuosity, etc. are judged, and the hook load and turntable torque are predicted, so as to realize real-time monitoring of wellbore conditions and operating conditions during drilling. The calculation accuracy of friction coefficient is improved, and then the monitoring accuracy of drilling operating conditions and wellbore conditions is improved, and the safety of drilling operations is improved.

[0098] In this specification, each embodiment of the above method is described in a progressive manner, and the same or similar parts between the embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments. For relevant parts, refer to the partial description of the method embodiment.

[0099] Based on the above-mentioned method for monitoring drilling operations based on friction coefficient, one or more embodiments of this specification also provide a device for monitoring drilling operations based on friction coefficient. The device may include a system (including a distributed system), software (application), module, component, server, client, etc. that uses the method of the embodiment of this specification and is combined with the necessary implementation hardware. Based on the same innovative concept, the device in one or more embodiments provided in the embodiment of this specification is as shown in the following embodiments. Since the implementation scheme and method of the device to solve the problem are similar, the implementation of the specific device in the embodiment of this specification can refer to the implementation of the aforementioned method, and the repetitions will not be repeated. As used below, the term "unit" or "module" can implement a combination of software and / or hardware for predetermined functions. Although the systems and devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceived.

[0100] Figure 6 FIG. 1 is a schematic diagram of a device for monitoring drilling operations based on friction coefficient in one embodiment of the present specification. Figure 6 As shown, the device for monitoring drilling operations based on friction coefficient provided in some embodiments of this specification may specifically include:

[0101] A parameter calculation module 61, for calculating the hook load and the rotary table torque at different well depths based on the friction coefficient;

[0102] The weight configuration module 62 is used to calculate the weight value of the friction coefficient of each data point according to the distance of each data point from the bottom of the wellbore;

[0103] The objective function calculation module 63 is used to calculate the weighted average value of the calculation error of the hook load or the rotary table torque at different well depths based on the weight value of the friction coefficient corresponding to each data point, and use the weighted average value as the objective function;

[0104] The friction coefficient solving module 64 is used to solve the objective function to obtain the target friction coefficient when the objective function takes the minimum value;

[0105] The monitoring module 65 is used to monitor the wellbore conditions and operation conditions during the drilling operation based on the target friction coefficient.

[0106] The device for monitoring drilling operations based on the friction coefficient provided in the embodiments of this specification takes into account the influence of the time effect in the inversion process of the friction coefficient, introduces a weight coefficient related to the well depth, and uses the weighted average error of the calculated value of the hook load or the turntable torque as the objective function, which can realize the dynamic inversion of the friction coefficient during the drilling process, and judge the changes in the wellbore cleaning condition, formation properties, wellbore tortuosity, etc. according to the inversion result of the friction coefficient, and predict the hook load and turntable torque, so as to realize the real-time monitoring of the wellbore conditions and operating conditions during the drilling process. The calculation accuracy of the friction coefficient is improved, and then the accuracy of monitoring the drilling operating conditions and wellbore conditions is improved, and the safety of the drilling operation is improved.

[0107] In some embodiments of this specification, the weight configuration module is specifically used to calculate the weight value of the friction coefficient using the following formula:

[0108]

[0109] Among them, ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, d i represents the distance from the i-th data point to the bottom of the wellbore, d i It is the serial number of each data point sorted from the bottom of the well upward, where each data point is sorted from small to large according to the well depth, p represents the power index, p≥0.

[0110] The embodiment of this specification takes into account the influence of time effect in the inversion process of friction coefficient, introduces a weight coefficient related to the well depth, and the larger the power exponent in the weight coefficient, the closer the change trend of the calculated value of the hook load and the turntable torque is to the change trend of the recorded value of the hook load and the turntable torque near the prediction point when the prediction section length is small. Therefore, based on the dynamic inversion results of the friction coefficient, the hook load and the turntable torque can be accurately predicted, thereby improving the accuracy of the safety monitoring of the drilling operation and improving the safety of the drilling operation.

[0111] It should be noted that the above-mentioned device may also include other implementation modes according to the description of the corresponding method embodiment. The specific implementation modes may refer to the description of the corresponding method embodiment, and will not be described one by one here.

[0112] The embodiments of this specification also provide a device for monitoring drilling operations based on friction coefficient, the device comprising at least one processor and a memory for storing instructions executable by the processor, and when the instructions are executed by the processor, the method for monitoring drilling operations based on friction coefficient in the above embodiments is implemented, such as:

[0113] Calculate the hook load and rotary table torque at different well depths based on the friction coefficient;

[0114] Calculate the weight value of the friction coefficient of each data point according to the distance between each data point and the bottom of the wellbore;

[0115] Calculate the weighted average of the calculation errors of the hook load or the rotary table torque at different well depths based on the weight values ​​of the friction coefficient corresponding to each data point, and use the weighted average as the objective function;

[0116] Solving the objective function to obtain a target friction coefficient when the objective function takes a minimum value;

[0117] The wellbore conditions and operating conditions during the drilling operation are monitored based on the target friction coefficient.

[0118] It should be noted that the above-mentioned device may also include other implementation modes according to the description of the method embodiment. The specific implementation modes may refer to the description of the relevant method embodiment, which will not be described one by one here.

[0119] The methods or devices of the above embodiments provided in this specification can implement business logic through computer programs and record them on storage media, and the storage media can be read and executed by computers to achieve the effects of the solutions described in the embodiments of this specification.

[0120] The method embodiments provided in the embodiments of this specification can be executed in a mobile terminal, a computer terminal, a server or a similar computing device. Taking running on a server as an example, Figure 7 This is a hardware structure block diagram of a server for monitoring drilling operations based on friction coefficient in one embodiment of this specification. The computer terminal may be a server for monitoring drilling operations based on friction coefficient or a processing device for monitoring drilling operations based on friction coefficient in the above embodiment. Figure 7The server 10 shown may include one or more (only one is shown in the figure) processors 100 (the processor 100 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA), a non-volatile memory 200 for storing data, and a transmission module 300 for communication functions. Those skilled in the art will understand that Figure 7 The structure shown is only for illustration and does not limit the structure of the above electronic device. Figure 7 More or fewer components shown in the figure may also include other processing hardware, such as a database or multi-level cache, GPU, or other hardware with Figure 7 Different configurations are shown.

[0121] The non-volatile memory 200 can be used to store software programs and modules of application software, such as the program instructions / modules corresponding to the taxi data processing method in the embodiment of this specification. The processor 100 executes various functional applications and resource data updates by running the software programs and modules stored in the non-volatile memory 200. The non-volatile memory 200 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the non-volatile memory 200 may further include a memory remotely arranged relative to the processor 100, and these remote memories may be connected to the computer terminal via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a bureau and a network, a mobile communication network, and combinations thereof.

[0122] The transmission module 300 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of a computer terminal. In one example, the transmission module 300 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission module 300 can be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0123] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0124] The above-mentioned method or device for monitoring drilling operations based on friction coefficient provided in the embodiments of this specification can be implemented by a processor in a computer executing corresponding program instructions, such as using the C++ language of the Windows operating system to implement it on a PC, a Linux system, or other systems such as Android and iOS system programming languages ​​to implement it on a smart terminal, as well as based on the processing logic of a quantum computer.

[0125] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the hardware + program embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0126] Although one or more embodiments of the present specification provide method operation steps such as embodiments or flow charts, more or less operation steps may be included based on conventional or non-creative means. The order of steps listed in the embodiment is only one way of executing the order of many steps, and does not represent the only execution order. When the device or terminal product in practice is executed, it can be executed in sequence or in parallel according to the method shown in the embodiment or the accompanying drawings (for example, a parallel processor or a multi-threaded processing environment, or even a distributed resource data update environment). The term "include", "include" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, product or equipment including a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such process, method, product or equipment. In the absence of more restrictions, it is not excluded that there are other identical or equivalent elements in the process, method, product or equipment including the elements. The first, second, etc. words are used to represent the name, and do not represent any specific order.

[0127] For the convenience of description, the above devices are described in various modules according to their functions. Of course, when implementing one or more of the present specification, the functions of each module can be implemented in the same or more software and / or hardware, or the module implementing the same function can be implemented by a combination of multiple sub-modules or sub-units, etc. The device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0128] Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. In the description of this specification, the description of the reference term "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of this specification. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0129] The above are only examples of one or more embodiments of this specification and are not intended to limit one or more embodiments of this specification. For those skilled in the art, one or more embodiments of this specification may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this specification should be included in the scope of the claims.

Claims

1. A method for monitoring drilling operations based on friction coefficient, characterized in that: The method comprises: Calculate the hook load and rotary table torque at different well depths based on the friction coefficient; Calculate the weight value of the friction coefficient of each data point according to the distance between each data point and the bottom of the wellbore; Calculate the weighted average of the calculation errors of the hook load or the rotary table torque at different well depths based on the weight values ​​of the friction coefficient corresponding to each data point, and use the weighted average as the objective function; Solving the objective function to obtain a target friction coefficient when the objective function takes a minimum value; Monitoring the borehole conditions and operating conditions during the drilling operation based on the target friction coefficient; Calculating the friction coefficient weight value of each data point according to the distance of each data point from the bottom of the wellbore includes using the following formula to calculate the friction coefficient weight value: Among them, ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, d i represents the distance from the i-th data point to the bottom of the wellbore, d i is the serial number of each data point sorted from the bottom of the well upward, where each data point is sorted from small to large according to the well depth, p represents the power index, p≥0; The objective function is calculated using the following formula: Wherein, Err represents the objective function, c1 and c2 represent the coefficient values ​​of two different working conditions, namely, string sliding and string rotation. When the string slides, c1=1, c2=0, and when the string rotates, c1=0, c2=1. ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, hk i represents the hook load measured at the well depth corresponding to the i-th data point, tor i represents the rotary table torque measured at the well depth corresponding to the i-th data point, hk cali represents the hook load calculated at the well depth corresponding to the ith data point, tor cali It represents the rotary table torque calculated at the well depth corresponding to the ith data point.

2. The method according to claim 1, characterized in that The power index is at least one of 0, 1, and 2.

3. The method according to claim 1, characterized in that The friction coefficient includes the friction coefficient of the casing section and the friction coefficient of the open hole section.

4. The method according to claim 1, characterized in that The weighted average value of the calculation error of the hook load or the rotary table torque at different well depths is calculated based on the friction coefficient weight value corresponding to each data point, including: For the data points of the tubing sliding operation, the weighted average value of the hook load at the corresponding well depth is calculated based on the weight value of the friction coefficient corresponding to each data point; For the data points of the pipe string rotation operation, the weighted average value of the rotary table torque corresponding to the well depth is calculated based on the friction coefficient weight value corresponding to each data point; The sum of the weighted average value of the hook load and the weighted average value of the turntable torque is taken as the weighted average value.

5. The method according to claim 1, characterized in that The monitoring of the borehole conditions and the operating conditions during the drilling operation based on the target friction coefficient includes: As the drilling depth increases, the target friction coefficient corresponding to different well depths is obtained in turn; Monitor the wellbore conditions at different well depths based on the changing trend of the target friction coefficient at different well depths; The hook load and turntable torque at different well depths are predicted based on the target friction coefficient at different well depths. Whether the drilling operation is overloaded is determined based on the calculated hook load and turntable torque, and the operating conditions during the drilling process are monitored.

6. A device for monitoring drilling operations based on friction coefficient, characterized in that: The device comprises: Parameter calculation module, used to calculate the hook load and rotary table torque at different well depths based on the friction coefficient; The weight configuration module is used to calculate the weight value of the friction coefficient of each data point according to the distance of each data point from the bottom of the wellbore; An objective function calculation module is used to calculate the weighted average value of the calculation error of the hook load or the rotary table torque at different well depths based on the weight value of the friction coefficient corresponding to each data point, and use the weighted average value as the objective function; A friction coefficient solving module, used for solving the objective function to obtain a target friction coefficient when the objective function takes a minimum value; A monitoring module, used for monitoring the wellbore conditions and operating conditions during the drilling operation based on the target friction coefficient; The weight configuration module is specifically used to calculate the friction coefficient weight value using the following formula: Among them, ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, d i represents the distance from the i-th data point to the bottom of the wellbore, d i is the serial number of each data point sorted from the bottom of the well upward, where each data point is sorted from small to large according to the well depth, p represents the power index, p≥0; The objective function is calculated using the following formula: Wherein, Err represents the objective function, c1 and c2 represent the coefficient values ​​of two different working conditions, namely, string sliding and string rotation. When the string slides, c1=1, c2=0, and when the string rotates, c1=0, c2=1. ρ i represents the friction coefficient weight value of the i-th data point, n represents the total number of data points, hk i represents the hook load measured at the well depth corresponding to the i-th data point, tor i represents the rotary table torque measured at the well depth corresponding to the i-th data point, hk cali represents the hook load calculated at the well depth corresponding to the ith data point, tor cali It represents the rotary table torque calculated at the well depth corresponding to the ith data point.

7. A device for monitoring drilling operations based on friction coefficient, characterized in that: The device comprises at least one processor and a memory for storing processor executable instructions, and when the instructions are executed by the processor, the steps of any one of the methods of claims 1 to 5 are implemented.

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