Sticky card early warning method and device in casing running process of oil and gas well

Abstract

The invention discloses a sticking early warning method and device in the process of running a casing in an oil-gas well, and the method comprises the following steps: judging whether a pipe column is lifted or released according to the lifting and lowering state of the pipe column, the hanging load variation and the hook height variation after the pipe column is released; after the tubular column is lifted or inactivated, the starting hanging load of the tubular column is obtained according to the hanging load variation, and the current static friction resistance is calculated; and according to the calculated historical static friction resistance, the corresponding pipe column static time and the pipe column length, the static friction resistance, the starting hanging load and the maximum allowable static time of the next operation are predicted, and early warning is made. According to the method, the static friction resistance change condition in the casing running process is monitored, and the static friction resistance value is predicted in real time, so that sticking early warning in the casing running process is realized, the occurrence of casing sticking accidents can be effectively prevented, the drilling operation safety is guaranteed, and the operation efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the field of information technology of oil drilling and completion engineering, and in particular relates to a method and device for early warning of sticking in a casing process in an oil and gas well. Background Art

[0002] Casing operation is an important drilling engineering technology in the oil industry, which can effectively control rock collapse, wellbore instability and other problems during the drilling process. During the casing running process, the current method for predicting casing stuck is usually to rely on the calculation of the hook load route map based on the mechanics of the pipe string, and confirm the size and trend of the friction coefficient according to the real-time hook load distribution during the running process, so as to timely predict the casing stuck. In practical applications, the above method usually requires timely manual response, resulting in high labor cost requirements and high missed reporting rate. In addition, this method is mainly used to predict the dynamic friction coefficient and is not suitable for casing stuck warning. Summary of the invention

[0003] The problem to be solved by the present invention is to provide a method and device for early warning of sticking during casing lowering in an oil and gas well. The method is suitable for realizing early warning of sticking during casing lowering.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for early warning of sticking in casing in oil and gas wells, comprising the following steps:

[0005] S1: After the pipe string is unstuck, determine whether the pipe string is lifted or released based on the lifting and lowering status of the pipe string, as well as the change in the hanging weight and the change in the height of the hook;

[0006] S2: After the pipe string is lifted or released, the starting hanging weight of the pipe string is obtained according to the hanging weight change, and the current static friction resistance is calculated;

[0007] S3: Based on the calculated historical static friction resistance and the corresponding pipe string static time and pipe string length, the static friction resistance, starting hanging weight, and maximum allowable static time of the next operation are predicted and an early warning is issued.

[0008] Further, the S1 comprises the following steps:

[0009] S11: read the real-time data after the pipe string is released from the jam and set the activity threshold A;

[0010] S12: Record the hook hanging weight and hook position at the current time point;

[0011] S13: Calculate the difference ΔW of the hook hanging weight and the difference ΔH of the hook position between the current time point and the previous time point respectively;

[0012] S14: Determine the activity status of the pipe string.

[0013] Further, in S14, calculate ΔW / ΔH; when the pipe string is in the upward lifting state and ΔW / ΔH < A, record the active state of the pipe string as "lifting and activating"; when the pipe string is in the downward lowering state and ΔW / ΔH < A, record the active state of the pipe string as "lowering and activating"; otherwise, give an alarm.

[0014] Further, S2 includes the following steps

[0015] S21: When the active state of the pipe string is "lifting and activating", record the maximum upward hook load before lifting as the upward starting hook load; when the pipe string is in the "lowering and activating" state, record the minimum downward hook load before lowering as the downward starting hook load.

[0016] S22: Record the free hook load of the lowered pipe string.

[0017] S23: When the active state of the pipe string is "lifting and activating", subtract the free downward hook load from the upward starting hook load as the static friction resistance, denoted as ΔF; when the pipe string is in the "lowering and activating" state, subtract the downward starting hook load from the free downward hook load as the static friction resistance, denoted as ΔF.

[0018] Further, S3 includes the following steps

[0019] S31: Calculate the empirical parameter c according to the empirical formula ΔF = cTL.

[0020] S32: According to the empirical formula ΔF = cTL, the empirical parameter c, the maximum allowable upward hook load W max , the minimum allowable downward hook load W min , calculate the maximum allowable static time.

[0021] S33: When the pipe string is stationary, monitor the static time T, and according to the empirical formula, predict the static friction resistance, upward starting torque and downward starting torque in real time.

[0022] S34: When the pipe string is stationary, monitor the static time T and give a risk warning.

[0023] Further, in S32, the calculation formula for the maximum allowable static time is

[0024]

[0025] where W 管柱 is the theoretical free hook load of the pipe string.

[0026] Further, in S33, the static friction resistance predicted in real time is ΔF = cTL, the upward starting torque = ΔF + W 管柱 , the downward starting torque = W 管柱 -ΔF.

[0027] Further, in S34, when T > Tmax1 When T>T max2 When the card is stuck, an alert will be issued, indicating that there is a risk of not being able to release the card.

[0028] Furthermore, the present invention also provides a device for early warning of sticking during casing drilling in oil and gas wells, which is applicable to the above-mentioned early warning method for sticking during casing drilling in oil and gas wells, and includes a pipe string activity judgment module, a static friction calculation module, and a static friction prediction module:

[0029] The pipe string activity judgment module is used to judge whether the pipe string is lifted or released according to the lifting and lowering state of the pipe string, the change in the hanging weight and the change in the height of the big hook;

[0030] The static friction resistance calculation module is used to obtain the starting hanging weight of the pipe string according to the hanging weight change after the pipe string is lifted or released, and calculate the current static friction resistance;

[0031] The static friction resistance prediction module is used to predict the static friction resistance, starting hanging weight, maximum allowable static time of the next operation and issue an early warning based on the calculated historical static friction resistance and the corresponding pipe string static time and pipe string length.

[0032] The advantages and positive effects of the present invention are:

[0033] The present invention realizes early warning of sticking during the casing lowering process by monitoring the static friction resistance change during the casing lowering process and predicting the static friction resistance value in real time, which can effectively prevent the occurrence of casing sticking accidents, ensure the safety of drilling operations, and improve operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is an overall flow chart of an embodiment of the present invention.

[0035] Figure 2 It is a schematic diagram of the overall structure of an embodiment of the present invention.

[0036] Figure 3 Schematic diagram of a pipe string activity judgment module according to an embodiment of the present invention.

[0037] Figure 4 Schematic diagram of a static friction calculation module according to an embodiment of the present invention.

[0038] Figure 5 Schematic diagram of a static friction prediction module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0041] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] The embodiments of the present invention are further described below in conjunction with the accompanying drawings:

[0043] like Figure 1 As shown, a method for early warning of sticking in casing in oil and gas wells comprises the following steps:

[0044] S1: After the pipe string is unstuck, determine whether the pipe string is lifted or released based on the lifting and lowering status of the pipe string, as well as the change in the hanging weight and the change in the height of the hook. Specifically, S1 includes the following steps:

[0045] S11: Read the real-time data after the pipe string is unstuck and set the activity threshold A.

[0046] S12: Record the hook hanging weight and hook position at the current time point.

[0047] S13: Calculate the value of the hook weight at the current time point minus the hook weight at the previous time point and record it as ΔW, calculate the current hook position minus the hook position at the previous time point and record it as ΔH, and calculate ΔW / ΔH.

[0048] S14: When the pipe string is in the upward lifting state and ΔW / ΔH < A, record the activity state of the pipe string as "lifting and activating"; when the pipe string is in the downward lowering state and ΔW / ΔH < A, record the activity state of the pipe string as "lowering and activating"; otherwise, give an early warning.

[0049] S2: After the pipe string is lifted and activated or lowered and activated, obtain the starting hook load of the pipe string according to the change in hook load, and calculate the current static friction resistance. Specifically, S2 includes the following steps:

[0050] S21: When the activity state of the pipe string is "lifting and activating", record the maximum upward hook load before lifting and activating as the upward starting hook load; when the pipe string is in the "lowering and activating" state, record the minimum downward hook load before lowering and activating as the downward starting hook load.

[0051] S22: Record the free hook load of the lowered pipe string.

[0052] S23: When the activity state of the pipe string is "lifting and activating", subtract the free hook load of lowering from the upward starting hook load as the static friction resistance, denoted as ΔF; when the pipe string is in the "lowering and activating" state, subtract the downward starting hook load from the free hook load of lowering as the static friction resistance, denoted as ΔF.

[0053] S3: According to the calculated historical static friction resistance, the corresponding pipe string stationary time, and the pipe string length, predict the static friction resistance, starting hook load, maximum allowable stationary time for the next operation and give an early warning. Specifically, S3 includes the following steps:

[0054] S31: Calculate the empirical parameter c according to the empirical formula ΔF = cTL.

[0055] S32: According to the empirical formula ΔF = cTL, the empirical parameter c, the maximum allowable upward hook load W max , the minimum allowable downward hook load W min , calculate the maximum allowable stationary time.

[0056]

[0057] where W 管柱 is the theoretical free hook load of the pipe string.

[0058] S33: When the pipe string is stationary, monitor the stationary time T. According to the empirical formula, predict the static friction resistance ΔF = cTL in real time, the upward starting torque = ΔF + W 管柱 , the downward starting torque = W 管柱 -ΔF.

[0059] S34: When the pipe string is stationary, monitor the stationary time T. When T > T max1 , give a sticking warning, indicating the risk of inability to lift and activate; when T > T max2 , give a sticking warning, indicating the risk of inability to lower and activate.

[0060] like Figure 2-5 As shown, the present invention also provides a sticking warning device during casing drilling in oil and gas wells, which is applicable to the above-mentioned sticking warning method during casing drilling in oil and gas wells, and includes a pipe string activity judgment module, a static friction calculation module, and a static friction prediction module.

[0061] The pipe string activity judgment module is used to judge whether the pipe string is lifted or lowered according to the lifting and lowering status of the pipe string, as well as the change in the hanging weight and the change in the height of the big hook.

[0062] The static friction calculation module is used to obtain the starting hanging weight of the pipe string according to the change of the hanging weight after the pipe string is lifted or released, and calculate the current static friction resistance.

[0063] The static friction resistance prediction module is used to predict the static friction resistance, starting hanging weight, maximum allowable static time of the next operation and issue an early warning based on the calculated historical static friction resistance and the corresponding pipe string static time and pipe string length.

[0064] The advantages and positive effects of the present invention are:

[0065] The present invention realizes early warning of sticking during the casing lowering process by monitoring the static friction resistance change during the casing lowering process and predicting the static friction resistance value in real time, which can effectively prevent the occurrence of casing sticking accidents, ensure the safety of drilling operations, and improve operation efficiency.

[0066] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for early warning of sticking during casing drilling in oil and gas wells, characterized by: It includes the following steps, S1: After the pipe string is released from the set-down position, based on the up-and-down state of the pipe string, as well as the change in hook load and the change in hook height, determine whether the pipe string is lifted or lowered actively; S2: After the pipe string is lifted or lowered actively, based on the change in hook load, obtain the starting hook load of the pipe string and calculate the current static friction resistance; S3: Based on the calculated historical static friction resistance, the corresponding pipe string static time, and the pipe string length, predict the static friction resistance, starting hook load, maximum allowable static time for the next operation and give an early warning.

2. The method for early warning of sticking during casing drilling in oil and gas wells according to claim 1, characterized in that: The said S1 includes the following steps, S11: Read the real-time data after the pipe string is released from the set-down position and set the activity threshold A; S12: Record the hook load and hook position at the current time point; S13: Calculate the difference in hook load ΔW and the difference in hook position ΔH between the current time point and the previous time point respectively; S14: Judge the activity state of the pipe string.

3. The method for early warning of sticking during casing drilling in oil and gas wells according to claim 2 is characterized in that: In the said S14, calculate ΔW / ΔH; when the pipe string is in the lifting state and ΔW / ΔH < A, record the activity state of the pipe string as lifted actively; when the pipe string is in the lowering state and ΔW / ΔH < A, record the activity state of the pipe string as lowered actively; otherwise, give an early warning.

4. A method for early warning of sticking during casing drilling in oil and gas wells according to any one of claims 1 to 3, characterized in that: The said S2 includes the following steps, S21: When the activity state of the pipe string is lifted actively, record the maximum lifting hook load before lifting actively as the starting lifting hook load; when the pipe string is in the lowered actively state, record the minimum lowering hook load before lowering actively as the starting lowering hook load; S22: Record the free hook load of the lowered pipe string; S23: When the activity state of the pipe string is lifted actively, subtract the free hook load of the lowered pipe string from the starting lifting hook load as the static friction resistance, denoted as ΔF; when the pipe string is in the lowered actively state, subtract the starting lowering hook load from the free hook load of the lowered pipe string as the static friction resistance, denoted as ΔF.

5. The method for early warning of sticking during casing drilling in oil and gas wells according to claim 4 is characterized in that: The said S3 includes the following steps, S31: Calculate the empirical parameter c according to the empirical formula ΔF = cTL; S32: According to the empirical formula ΔF = cTL, the empirical parameter c, the maximum allowable lifting weight W max , minimum allowable lowering weight W min , calculate the maximum allowable stationary time; S33: When the pipe string is stationary, monitor the static time T, and according to the empirical formula, predict the static friction resistance, starting lifting torque, and starting lowering torque in real time; S34: When the pipe string is stationary, monitor the static time T and give a risk warning.

6. The method for early warning of sticking during casing drilling in oil and gas wells according to claim 5 is characterized in that: In the said S32, the calculation formula for the maximum allowable static time is, Among them, W 管柱 is the theoretical free hanging weight of the pipe string.

7. The method for early warning of sticking during casing drilling in oil and gas wells according to claim 6, characterized in that: In the above S33, the static friction resistance ΔF=cTL is predicted in real time, and the lifting starting torque=ΔF+W 管柱 , starting torque = W 管柱 -ΔF.

8. The method for early warning of sticking during casing drilling in oil and gas wells according to claim 6 or 7, characterized in that: In S34, when T>T max1 When T>T max2 When the card is stuck, an alert will be issued, indicating that there is a risk of not being able to release the card.

9. A device for early warning of casing sticking during the process of drilling casing in oil and gas wells, applicable to the method for early warning of casing sticking during the process of drilling casing in oil and gas wells as claimed in any one of claims 1 to 8, characterized in that: It includes a pipe string activity condition judgment module, a static friction resistance calculation module, and a static friction resistance prediction module: The said pipe string activity condition judgment module is used to determine whether the pipe string is lifted or lowered actively according to the up-and-down state of the pipe string, as well as the change in hook load and the change in hook height; The said static friction resistance calculation module is used to obtain the starting hook load of the pipe string and calculate the current static friction resistance based on the change in hook load after the pipe string is lifted or lowered actively; The said static friction resistance prediction module is used to predict the static friction resistance, starting hook load, maximum allowable static time for the next operation and give an early warning based on the calculated historical static friction resistance, the corresponding pipe string static time, and the pipe string length.

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