Method and system for testing strength of shell plugging material and pressure applying device

Abstract

The invention discloses a shell plugging material strength testing method and system and a pressure applying device.An obtained shell sample is subjected to a series of processing according to the actual downhole temperature and pressure difference, firstly, the obtained shell sample is heated, after heating is finished, the shell sample is subjected to a series of operation of pressure applying, pressure stabilizing and pressure releasing, and the shell plugging material strength is obtained; then the processed shell samples are further screened, the breakage rate of the shell materials is calculated according to the weight change of the shell samples before and after screening, the strength performance of the samples is represented, the strength index of the shell samples is obtained, and therefore high-strength leaking stoppage materials can be preferably selected in advance in later drilling construction; and the phenomenon that well leakage occurs again due to insufficient strength of the leaking stoppage material is avoided, normal and stable drilling operation is guaranteed, and reliable technical support and guarantee are provided for improving the leaking stoppage success rate.

Description

Technical Field

[0001] The invention belongs to the technical field of drilling plugging construction, and relates to a strength testing method, system and pressure applying device of a fruit shell plugging material. Background Art

[0002] During plugging construction, plugging materials can be pulled together to form a bridge structure, thereby sealing leaking strata and cracks. In drilling plugging construction technology, some plugging materials are not strong enough, which will cause well leakage to occur again and affect normal drilling operations. Therefore, it is necessary to obtain the plugging strength of the material in advance and carry out construction in a targeted manner to facilitate the smooth implementation of the subsequent plugging work and avoid well leakage during the construction process.

[0003] However, the current testing industry still has a gap in determining the strength performance of fruit shell plugging materials. It is impossible to obtain the strength of fruit shell plugging materials and form control indicators to guide subsequent drilling construction. Summary of the invention

[0004] The purpose of the present invention is to solve the problems in the prior art and to provide a method, system and pressure device for testing the strength of fruit shell plugging materials. According to the principle that the particle size of fruit shell plugging materials decreases due to brittle fracture under pressure, a set of fruit shell plugging material strength evaluation method and device is developed. By simulating the plugging construction process and using real conditions such as downhole temperature and pressure difference, the particle size is screened by a particle size sieve to confirm the crushing rate of the sample, so as to characterize the strength performance of the sample, so as to select high-strength plugging materials and avoid the recurrence of well leakage due to insufficient strength of the plugging materials, thereby affecting the drilling operation.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for testing the strength of fruit shell plugging materials comprises the following steps:

[0007] S1: obtaining a fruit shell sample and heating the obtained fruit shell sample;

[0008] S2: applying pressure to the heated fruit shell sample until the pressure reaches a preset pressure difference and then stabilizing the pressure;

[0009] S3: after the pressure stabilization is completed, the fruit shell sample is depressurized, and then the depressurized fruit shell sample is screened, and the screened fruit shell sample is obtained;

[0010] S4: Based on the weight difference of the fruit shell samples before and after screening, the crushing rate of the fruit shell materials is calculated to characterize the strength of the samples.

[0011] A further improvement of the present invention is:

[0012] The step S1 comprises the following steps:

[0013] Weigh the obtained fruit shell samples, recorded as m 1 ;

[0014] The fruit shell sample is placed in a sample cup, and the sample cup is placed in a heating device, and heated to a preset temperature.

[0015] In the step S1, the preset temperature is the downhole temperature of the pre-plugged target well.

[0016] The preset pressure difference in step S2 is the downhole pressure difference of the pre-plugged target well.

[0017] In step S2, the voltage stabilization time is 10 minutes.

[0018] In the step S2, the fruit shell sample is depressurized by a hydraulic press.

[0019] In step S5, the strength of the fruit shell material is calculated by formula (1):

[0020]

[0021] In the formula, m 1 Indicates the mass of the fruit shell sample before pressure is applied; m 2 Indicates the mass of the sample after screening and pressurization.

[0022] A device for applying pressure to fruit shell plugging materials, used in the method for testing the strength of fruit shell plugging materials described in the present invention, comprises a base (5), a sample cup (4) is arranged in the base (5), a heating sleeve (3) is sleeved on the outer side of the sample cup (4), a hydraulic cylinder assembly is arranged at the upper end of the base, and the lower end of the hydraulic cylinder assembly corresponds to the port of the sample cup (4).

[0023] The hydraulic cylinder assembly comprises a hydraulic cylinder (1), wherein the hydraulic cylinder (1) passes through the upper end of the base (5), and the lower end of the hydraulic cylinder (1) corresponds to the port of the sample cup (4);

[0024] The hydraulic cylinder is connected to an oil pump (7), and a pressure gauge (6) is provided on the hydraulic cylinder.

[0025] A fruit shell plugging material strength testing system, comprising a sample heating module, a sample pressure module, a sample screening module and a sample strength calculation module;

[0026] A sample heating module, used for obtaining fruit shell samples and heating the obtained fruit shell samples;

[0027] The sample pressure module is used to apply pressure to the heated fruit shell sample until the pressure reaches a preset pressure difference and then stabilize the pressure;

[0028] The sample screening module is used to decompress the fruit shell samples after the pressure stabilization is completed, and then screen the decompressed fruit shell samples to obtain the screened fruit shell samples;

[0029] The sample strength calculation module is used to calculate the strength of the fruit shell material based on the screened fruit shell samples.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The invention discloses a method for testing the strength of fruit shell plugging materials. According to the actual downhole temperature and pressure difference, a series of processing is performed on the obtained fruit shell samples. First, the obtained fruit shell samples are heated. After the heating, a series of operations such as pressurizing, stabilizing pressure and unloading pressure are performed on the obtained fruit shell samples. Then, the processed fruit shell samples are screened. According to the weight difference of the fruit shell samples before and after the screening, the strength of the fruit shell materials is calculated to characterize the sample strength performance and obtain the strength index of the fruit shell samples, so that high-strength plugging materials can be selected in advance in the later drilling construction to avoid the recurrence of well leakage due to insufficient strength of the plugging materials, thereby ensuring the normal and stable progress of the drilling operation and providing reliable technical support and guarantee for improving the plugging success rate.

[0032] Furthermore, in the testing method disclosed in the present invention, when the fruit shell samples are heated in the early stage, the preset temperature is the same as the downhole temperature of the well to be constructed, and the parameters of the target well are used as indicators, thereby improving the accuracy of the strength indicators finally obtained.

[0033] Furthermore, in the testing method disclosed in the present invention, the pressure conditions of the fruit shell samples are the same as the downhole pressure difference conditions of the target well to be constructed, and the experimental parameters are precisely applied to the specific construction object, overcoming the differences in downhole parameters of different wells, ensuring the accuracy of the final calculation results, and avoiding affecting the normal operation of the well during operation.

[0034] The present invention also discloses a pressure-applying device for fruit shell plugging materials, which can be applied in the testing method disclosed in the present invention, and comprises a sample cup, wherein the sample cup is used for storing fruit shell samples and performing heat treatment on the fruit shell samples. A hydraulic cylinder assembly is arranged at the upper end of the base, and the hydraulic cylinder assembly corresponds to the port of the sample cup, so as to pressurize the fruit shell samples in the cup. The pressure-applying device disclosed in the present invention can complete a series of heating and pressurizing processes, thus saving the time of the previous processes and facilitating the operation of the experiment.

[0035] Furthermore, in the pressure-applying device disclosed in the present invention, a pressure gauge is provided on the hydraulic cylinder, which can observe the pressure applied to the sample in real time, thereby facilitating the adjustment of the pressure applied. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 It is a structural diagram of the pressure applying device of the present invention;

[0038] Figure 2 It is a partial enlarged structural diagram of the present invention;

[0039] Among them: 1-hydraulic cylinder; 2-telescopic rod; 3-heating jacket; 4-sample cup; 5-base; 6-pressure gauge; 7-oil pump; 8-piston. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. 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.

[0042] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0043] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply 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 a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0044] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0045] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 connection 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.

[0046] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0047] See also Figure 1 The present invention discloses a strength testing method for fruit shell plugging materials. According to the principle that the particle size of fruit shell plugging materials decreases due to brittle fracture under pressure, the plugging construction process is simulated, and real conditions such as downhole temperature and pressure difference are used. The particle size is screened by a particle size sieve to confirm the crushing rate of the sample, so as to characterize the strength performance of the sample, so as to select high-strength plugging materials and avoid the recurrence of well leakage due to insufficient strength of the plugging materials, thereby affecting the drilling operation.

[0048] The method for testing the strength of a fruit shell plugging material disclosed in an embodiment of the present invention comprises the following steps:

[0049] Step 1: obtaining a fruit shell sample, and heating the obtained fruit shell sample;

[0050] Specifically include:

[0051] Weigh the obtained fruit shell samples several times, record as m 1 , place the fruit shell sample in the sample quilt and put the piston;

[0052] Furthermore, the sample cup is placed in a heating jacket and heated to the downhole temperature, and the target drilling parameters are used as indicators, which improves the accuracy of the strength indicators finally obtained.

[0053] Step 2: Apply pressure to the heated fruit shell sample until the pressure reaches a preset pressure difference and then stabilize the pressure;

[0054] Specifically include:

[0055] By applying pressure to the sample cup through a hydraulic press, the same pressure difference effect as that in the well is achieved, and the experimental parameters are accurately determined to the specific construction object, overcoming the differences in downhole parameters of different drilling wells, ensuring the accuracy of the final calculation results, and avoiding affecting the normal operation of the drilling during operation.

[0056] Furthermore, the voltage was stabilized for 10 minutes.

[0057] Step 3: after the pressure stabilization is completed, the fruit shell sample is depressurized, and then the depressurized fruit shell sample is screened, and the screened fruit shell sample is obtained;

[0058] Specifically include:

[0059] After the pressure is released, the pressurized plugging agent is sieved with a sieve with a higher mesh number and weighed. The weight is recorded as m 2 ;

[0060] Step 4: Calculate the strength of the husk material based on the weight difference between the husk sample before and after sieving.

[0061] Specifically include:

[0062] Obtain the weight difference of the fruit shell samples before and after pressure relief screening, and calculate the ratio of the weight difference to the fruit shell samples before pressure relief screening:

[0063] Calculated by formula (1):

[0064]

[0065] Where:

[0066] m 1 It indicates the mass of the fruit shell sample before pressure is applied, in grams (g);

[0067] m 2 It indicates the mass of the sample after screening and pressurization, in grams (g);

[0068] F represents the crushing rate of the fruit shell plugging material, in percentage (%).

[0069] The test method disclosed in the embodiment of the present invention calculates the strength of the husk material according to the weight difference of the husk sample before and after screening, so as to characterize the sample strength performance and obtain the strength index of the husk sample, so as to select high-strength plugging materials in advance in the later drilling construction, avoid the recurrence of well leakage due to insufficient strength of the plugging materials, ensure the normal and stable progress of the drilling operation, and further characterize its strength performance by determining the crushing rate of the husk plugging material, thereby providing reliable technical support and guarantee for improving the success rate of plugging.

[0070] Based on the testing method of the embodiment of the present invention, the present invention further discloses a pressure-applying device for fruit shell plugging materials, comprising a base 5, wherein a sample cup 4 is arranged in the base 5, a heating sleeve 3 is sleeved on the outer side of the sample cup 4, a hydraulic cylinder assembly is arranged at the upper end of the base, and the lower end of the hydraulic cylinder assembly corresponds to the port of the sample cup 4. The pressure-applying device disclosed in the present invention can complete a series of heating and pressure-applying processes, saves the time of the preliminary processes, and facilitates the operation of the experiment.

[0071] Furthermore, in the embodiment of the present invention, the hydraulic cylinder assembly includes a hydraulic cylinder 1, which passes through the upper end of the base 5, and a telescopic rod 2 is provided at the lower end of the hydraulic cylinder 1. The telescopic rod 2 corresponds to the port of the sample cup 4. The hydraulic cylinder 1 drives the telescopic rod 2 to move up and down to apply pressure and relieve pressure on the fruit shell sample in the sample cup 4.

[0072] Furthermore, in the embodiment of the present invention, the hydraulic cylinder 1 is connected to the oil pump 7 .

[0073] Furthermore, in the embodiment of the present invention, a pressure gauge 6 is provided on the hydraulic cylinder 1, which can observe the pressure applied to the sample in real time, thereby facilitating the adjustment of the pressure applied.

[0074] Further, in the embodiment of the present invention, the dimensions of the sample cup are 75 mm in depth, 53.8 mm in inner diameter, and 82 mm in outer diameter;

[0075] Furthermore, in the embodiment of the present invention, the size of the piston is 19 mm thick and 53.7 mm in diameter; the diameter of the rubber ring is 54 mm

[0076] Furthermore, in the embodiment of the present invention, the dimensions of the heating jacket are 126 mm in depth and 83 mm in inner diameter.

[0077] The embodiment of the present invention also discloses a fruit shell plugging material strength testing system, comprising a sample heating module, a sample pressure module, a sample screening module and a sample strength calculation module;

[0078] A sample heating module, used for obtaining fruit shell samples and heating the obtained fruit shell samples;

[0079] The sample pressure module is used to apply pressure to the heated fruit shell sample until the pressure reaches a preset pressure difference and then stabilize the pressure;

[0080] The sample screening module is used to decompress the fruit shell samples after the pressure stabilization is completed, and then screen the decompressed fruit shell samples to obtain the screened fruit shell samples;

[0081] The sample strength calculation module is used to calculate the strength of the fruit shell material based on the screened fruit shell samples.

[0082] Furthermore, the embodiment of the present invention discloses a specific experiment:

[0083] Weigh about 100g of fruit shell sample (m1) and put it into the standard sieve. Put the standard sieve containing the fruit shell sample on the standard test sieve machine and fix it. Oscillate it at a constant speed of 1400r / min for 3min.

[0084] Weigh a certain mass of the sieved sample (m1) into the pressure device, use a manual oil pump to add different pressures, and maintain the pressure for 10 minutes;

[0085] After unloading the pressure, screen the pressurized plugging agent and weigh it (m2), and calculate the crushing rate F = (m1-m2)÷m1×100.

[0086] The strength performance of the sample is evaluated by characterizing the corresponding relationship between pressure and crushing rate.

[0087] The strength test of different fruit shell plugging materials is as follows. For specific experimental data, see Table 1:

[0088] Table 1 Breakage rate analysis results

[0089]

[0090]

[0091]

[0092]

[0093] The present invention discloses a strength testing method, system and pressure-applying device for fruit shell plugging materials based on the principle that the particle size of brittle fracture of fruit shell plugging materials becomes smaller under pressure. The method simulates the plugging construction process, uses real conditions such as downhole temperature and pressure difference, and confirms the crushing rate of the sample by screening the particle size with a particle size sieve to characterize the strength performance of the sample, so as to select high-strength plugging materials and avoid the recurrence of well leakage due to insufficient strength of the plugging materials, thereby affecting the drilling operation.

[0094] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for testing the strength of fruit shell plugging materials, characterized in that: The following steps are involved: S1: obtaining a fruit shell sample and heating the obtained fruit shell sample; S2: applying pressure to the heated fruit shell sample until the pressure reaches a preset pressure difference and then stabilizing the pressure; S3: after the pressure stabilization is completed, the fruit shell sample is depressurized, and then the depressurized fruit shell sample is screened, and the screened fruit shell sample is obtained; S4: Based on the weight difference of the fruit shell samples before and after screening, the crushing rate of the fruit shell materials is calculated to characterize the strength of the samples.

2. A method for testing the strength of fruit shell plugging materials according to claim 1, characterized in that: The step S1 comprises the following steps: Weigh the obtained fruit shell samples and record them as m1; The fruit shell sample is placed in a sample cup, and the sample cup is placed in a heating device, and heated to a preset temperature.

3. A method for testing the strength of fruit shell plugging materials according to claim 2, characterized in that: In the step S1, the preset temperature is the downhole temperature of the pre-plugged target well.

4. A method for testing the strength of fruit shell plugging materials according to claim 1, characterized in that: The preset pressure difference in step S2 is the downhole pressure difference of the pre-plugged target well.

5. A method for testing the strength of fruit shell plugging materials according to claim 4, characterized in that: In step S2, the voltage stabilization time is 10 minutes.

6. A method for testing the strength of fruit shell plugging materials according to claim 5, characterized in that: In the step S2, the fruit shell sample is depressurized by a hydraulic press.

7. A method for testing the strength of fruit shell plugging materials according to claim 5, characterized in that: In step S5, the strength of the fruit shell material is calculated by formula (1): Wherein, m1 represents the mass of the fruit shell sample before pressure is applied; m2 represents the mass of the sample after screening and pressure application.

8. A device for applying pressure to fruit shell plugging materials, characterized in that: The method for testing the strength of fruit shell plugging materials as claimed in claim 1 comprises a base (5), a sample cup (4) is arranged in the base (5), a heating sleeve (3) is arranged on the outer side of the sample cup (4), a hydraulic cylinder assembly is arranged at the upper end of the base, and the lower end of the hydraulic cylinder assembly corresponds to the port of the sample cup (4).

9. A fruit shell plugging material pressure applying device according to claim 8, characterized in that: The hydraulic cylinder assembly comprises a hydraulic cylinder (1), wherein the hydraulic cylinder (1) passes through the upper end of the base (5), and the lower end of the hydraulic cylinder (1) corresponds to the port of the sample cup (4); The hydraulic cylinder is connected to an oil pump (7), and a pressure gauge (6) is provided on the hydraulic cylinder.

10. A fruit shell plugging material strength testing system according to claim 1, characterized in that: It includes a sample heating module, a sample pressure module, a sample screening module and a sample strength calculation module; A sample heating module, used for obtaining fruit shell samples and heating the obtained fruit shell samples; The sample pressure module is used to apply pressure to the heated fruit shell sample until the pressure reaches a preset pressure difference and then stabilize the pressure; The sample screening module is used to decompress the fruit shell samples after the pressure stabilization is completed, and then screen the decompressed fruit shell samples to obtain the screened fruit shell samples; The sample strength calculation module is used to calculate the strength of the fruit shell material based on the screened fruit shell samples.

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