Composite leak-stopping preflush fluid and preparation method thereof
By preparing a composite plugging pre-fluid, the problem of severe well leakage during drilling was solved, effectively isolating drilling fluid and cement slurry, reducing the risk of plugging failure, ensuring that cement slurry solidifies at the target formation, and improving drilling efficiency and safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SINOPEC OILFIELD SERVICE CORPORATION
- Filing Date
- 2024-12-06
- Publication Date
- 2026-06-09
Smart Images
Figure BDA0005175579730000071 
Figure BDA0005175579730000081 
Figure BDA0005175579730000082
Abstract
Description
Technical Field
[0001] This invention relates to the field of drilling plugging agent technology, and in particular to a composite plugging pre-fluid and its preparation method. Technical Background
[0002] Loss of drilling fluid (WSF) is a phenomenon where drilling mud, cement slurry, or other working fluids leak into the formation during drilling. Severe WSF is the most serious and difficult-to-solve type of loss. It typically occurs when drilling into caverns or large natural fractures, resulting in a continuous flow of fluid with no return. Sometimes, it can also occur when drilling long sections of formation with low pressure resistance. Severe WSF not only wastes drilling time and results in significant loss of drilling mud, but it can also lead to a series of complex situations such as stuck pipe, blowouts, and well collapse, ultimately causing wellbore abandonment and substantial economic losses.
[0003] Cement grout sealing is currently one of the main technical methods for addressing severe leakage. Generally, formation fissures and karst caves contain water (or mud), which inevitably thins the cement upon contact. This leads to two direct consequences: ① Thinning makes the cement grout easier to flow away and less likely to accumulate near the entrance of the leaking layer; ② Thinned cement grout is difficult to solidify or has significantly reduced setting strength, resulting in sealing failure. Currently, gel materials are used as a barrier between the cement and formation fluids to solve this problem. However, this construction process is costly, time-consuming, and risky.
[0004] During the cement slurry plugging process, a large amount of drilling fluid was used for plugging in the early stage, resulting in poor wellbore cleaning. Therefore, before using the plugging cement slurry, a suitable pre-fluid system should be developed to play the role of isolation and buffering, cleaning the wellbore, and retaining cement slurry during the process of displacing drilling fluid. Summary of the Invention
[0005] To solve the aforementioned clogging problem, this invention provides a composite pre-plugging fluid with good fluidity, settling stability, anti-fouling ability, and clogging effect, as well as its preparation method.
[0006] The present invention achieves the above objectives through the following technical solutions:
[0007] A composite leak-sealing pretreatment solution comprises the following components: 1 part by weight of water, 1-3% of release agent, 0.5-2% of suspension stabilizer, 1-6% of retarder, 0.5-2% of defoamer, 70-170% of weighting material, 1.5-5% of composite leak-sealing material, 1-5% of silicate fiber, and 1-1.5% of inorganic fiber; wherein the percentages of release agent, suspension stabilizer, retarder, defoamer, weighting material, composite leak-sealing material, silicate fiber, and inorganic fiber correspond to the respective mass percentages of release agent, suspension stabilizer, retarder, defoamer, weighting material, composite leak-sealing material, silicate fiber, and inorganic fiber relative to water.
[0008] It comprises the following components: 1 part by weight of water, 1-3% of release agent, 0.5-2% of suspension stabilizer, 2-5% of retarder, 0.5-1.5% of defoamer, 90-150% of weighting material, 1.5-4% of composite sealing material, 2-4% of silicate fiber, and 1-1.5% of inorganic fiber.
[0009] The separating agent is a cementing separator purchased from Sichuan Hongsheng Petroleum Engineering Technology Service Co., Ltd., and its specification is high-temperature solid, with the code GL-2; the suspension stabilizer is an oil well cement suspension stabilizer purchased from Tianjin Baoen Petroleum Engineering Technology Co., Ltd., and its specification is high-temperature type, with the code TAS-153; the retarder is a high-temperature oil well cement retarder purchased from Sichuan Hongsheng Petroleum Engineering Technology Service Co., Ltd., and its specification is high-temperature type, with the code BS200R; the defoamer is an oil well cement defoamer purchased from Beijing Pusiwei Petroleum Technology Co., Ltd. The defoaming agent for this oil well cement is a liquid organosilicon, with the code SUP12L; the weighting material is barite powder purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd., and the barite powder is of the premium grade; the composite plugging material is a composite plugging agent purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd., and the composite plugging agent is of the type II grade; the silicate fiber is a plugging agent silicate fiber purchased from Huixian Tianfeng Oilfield Additives Co., Ltd., and the plugging agent silicate fiber is of the type II grade; the inorganic fiber is chopped glass fiber reinforced concrete crack-resistant fiber, and the chopped glass fiber reinforced concrete crack-resistant fiber is of the 3mm-15mm grade.
[0010] A method for preparing the composite plugging pre-fluid includes the following steps:
[0011] Step 1: Add the separating agent to the water while stirring to dissolve the separating agent;
[0012] Step 2: After completing Step 1, add the suspension stabilizer while stirring to dissolve the suspension stabilizer;
[0013] Step 3: After completing Step 2, add the retarder while stirring to dissolve it.
[0014] Step 4: After completing Step 3, add defoamer while stirring to dissolve the defoamer and obtain a large sample of water;
[0015] Step 5: Add the composite sealing material, silicate fiber, and inorganic fiber to the weighting material, mix them evenly, and obtain a large sample of ash.
[0016] Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, stir and mix to obtain the composite plugging pre-treatment solution.
[0017] In step 1 of section 5, the water temperature is 23-25℃, the stirring speed is 600-1000 r / min, and the stirring time is at least 5 min.
[0018] In step 2, the stirring speed is 600-1000 r / min, and the stirring time is at least 5 min.
[0019] In step 3, the stirring speed is 600-1000 r / min, and the stirring time is at least 2 min.
[0020] In step 4, the stirring speed is 600-1000 r / min, and the stirring time is at least 2 min.
[0021] In step 6, the stirring speed is 4000-5000 r / min.
[0022] Compared with the prior art, the present invention has the following beneficial technical effects:
[0023] (1) Anti-pollution properties: Its main function is to isolate drilling fluid and cement slurry to prevent them from contacting and contaminating each other; (2) It has a certain plugging effect, especially in well environments with severe leakage. It is necessary to add plugging materials to the pre-filled fluid so that it can withstand a certain pressure after entering the formation, ensuring that the cement slurry can solidify quietly in the target layer; (3) The rheological properties of the composite plugging pre-filled fluid are suitable for turbulent displacement. It has low viscosity and low turbulent critical return velocity; (4) When the composite plugging pre-filled fluid comes into contact with mud and cement slurry, it has little impact on the strength development of cement stone. When the mixture is in a certain proportion, the cement slurry can still provide strength; (5) It also has the function of cleaning the well, providing a good solidification environment for cement. Detailed Implementation
[0024] The preferred embodiments of the present invention are described below. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.
[0025] In Examples 1 to 6 below, the percentages of the metered release agent, suspension stabilizer, retarder, defoamer, weighting material, composite sealing material, silicate fiber, and inorganic fiber correspond to the mass percentages of the release agent, suspension stabilizer, retarder, defoamer, weighting material, composite sealing material, silicate fiber, and inorganic fiber relative to water, respectively. For example, if the amount of water is 1000g, 3% release agent means that the amount of release agent is 3% of the amount of water, that is, the amount of release agent is 1000g multiplied by 3% equals 30g; other components are calculated in the same way and will not be repeated.
[0026] Example 1
[0027] A composite pre-sealant for sealing in this embodiment comprises the following components: 1000g water, 3% release agent, 2% suspension stabilizer, 1% retarder, 0.5% defoamer, 70% weighting material, 5% composite sealant material, 5% silicate fiber, and 1.5% inorganic fiber.
[0028] The preparation method of the composite plugging pre-fill fluid in this embodiment includes the following steps:
[0029] Step 1: Take 1000g of water at 23℃, add 3% of the release agent to the water while stirring at 600r / min, and stir for 5min to dissolve the release agent.
[0030] Step 2: After completing Step 1, add 2% suspension stabilizer while stirring at a speed of 600 r / min, and stir for 5 min to dissolve the suspension stabilizer.
[0031] Step 3: After step 2 is completed, add 1% retarder while stirring at a speed of 600 r / min and stir for 2 minutes to dissolve the retarder.
[0032] Step 4: After completing Step 3, add 0.5% defoamer while stirring at a speed of 600 r / min, and stir for 2 minutes to dissolve the defoamer and obtain a large sample of water.
[0033] Step 5: Weigh 70% of the weighting material, add 5% of the composite sealing material, 5% of the silicate fiber, and 1.5% of the inorganic fiber to the weighting material, mix evenly, and obtain a large sample of ash.
[0034] Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, and stir and mix at a stirring speed of 4000 r / min to obtain the composite plugging pretreatment solution.
[0035] Example 2
[0036] A composite pre-sealant for sealing leaks according to this embodiment comprises the following components: 1000g water, 3% release agent, 2% suspension stabilizer, 2% retarder, 0.5% defoamer, 90% weighting material, 4% composite sealant material, 4% silicate fiber, and 1.5% inorganic fiber.
[0037] The preparation method of the composite plugging pre-fill fluid in this embodiment includes the following steps:
[0038] Step 1: Take 1000g of water at 24℃, add 3% of the release agent to the water while stirring at 700r / min, and stir for 10min to dissolve the release agent.
[0039] Step 2: After completing Step 1, add 2% suspension stabilizer while stirring at a speed of 700 r / min, and stir for 10 min to dissolve the suspension stabilizer.
[0040] Step 3: After completing Step 2, add 2% retarder while stirring at a speed of 700 r / min, and stir for 5 minutes to dissolve the retarder.
[0041] Step 4: After completing Step 3, add 0.5% defoamer while stirring at 700 r / min, and stir for 5 min to dissolve the defoamer and obtain a large sample of water.
[0042] Step 5: Weigh 90% of the weighting material, add 4% of the composite sealing material, 4% of the organic fiber, and 1.5% of the inorganic fiber to the weighting material, mix evenly, and obtain a large sample of ash.
[0043] Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, and stir and mix at a stirring speed of 4200 r / min to obtain the composite plugging pretreatment solution.
[0044] Example 3
[0045] A composite pre-sealant for sealing in this embodiment comprises the following components: 1000g water, 2% release agent, 1% suspension stabilizer, 3% retarder, 1% defoamer, 110% weighting material, 4% composite sealant material, 4% silicate fiber, and 1% inorganic fiber.
[0046] The preparation method of the composite plugging pre-fill fluid in this embodiment includes the following steps:
[0047] Step 1: Measure 1000g of water at 25℃, add 2% release agent to the water while stirring at 800r / min, and stir for 15min to dissolve the release agent.
[0048] Step 2: After completing Step 1, add 1% suspension stabilizer while stirring at a speed of 800 r / min, and stir for 15 min to dissolve the suspension stabilizer.
[0049] Step 3: After completing Step 2, add 3% retarder while stirring at a speed of 800 r / min, and stir for 10 min to dissolve the retarder.
[0050] Step 4: After completing Step 3, add 1% defoamer while stirring at a speed of 800 r / min, and stir for 10 min to dissolve the defoamer and obtain a large sample of water.
[0051] Step 5: Weigh 110% of the weighting material, add 4% of the composite sealing material, 4% of the silicate fiber, and 1% of the inorganic fiber to the weighting material, mix evenly, and obtain a large sample of ash.
[0052] Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, and stir and mix at a stirring speed of 4500 r / min to obtain the composite plugging pretreatment solution.
[0053] Example 4
[0054] A composite pre-sealant for sealing in this embodiment comprises the following components: 1000g water, 2% release agent, 1% suspension stabilizer, 4% retarder, 1% defoamer, 130% weighting material, 3% composite sealant material, 3% silicate fiber, and 1% inorganic fiber.
[0055] The preparation method of the composite plugging pre-fill fluid in this embodiment includes the following steps:
[0056] Step 1: Measure 1000g of water at 23℃, add 2% release agent to the water while stirring at 900r / min, and stir for 25min to dissolve the release agent.
[0057] Step 2: After completing Step 1, add 1% suspension stabilizer while stirring at a speed of 900 r / min, and stir for 25 min to dissolve the suspension stabilizer.
[0058] Step 3: After completing Step 2, add 4% retarder while stirring at a speed of 900 r / min, and stir for 20 min to dissolve the retarder.
[0059] Step 4: After completing Step 3, add 1% defoamer while stirring at a speed of 900 r / min, and stir for 20 min to dissolve the defoamer and obtain a large sample of water.
[0060] Step 5: Weigh 130% of the weighting material, add 3% of the composite sealing material, 3% of the silicate fiber, and 1% of the inorganic fiber to the weighting material, mix evenly, and obtain a large sample of ash.
[0061] Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, and stir and mix at a stirring speed of 4800 r / min to obtain the composite plugging pretreatment solution.
[0062] Example 5
[0063] A composite pre-sealant for sealing leaks according to this embodiment comprises the following components: 1000g water, 1% release agent, 0.5% suspension stabilizer, 5% retarder, 1.5% defoamer, 150% weighting material, 1.5% composite sealant material, 2% silicate fiber, and 1% inorganic fiber.
[0064] The preparation method of the composite plugging pre-fill fluid in this embodiment includes the following steps:
[0065] Step 1: Measure 1000g of water at 23℃, add 1% of the release agent to the water while stirring at 1000r / min, and stir for 35min to dissolve the release agent.
[0066] Step 2: After completing Step 1, add 0.5% suspension stabilizer while stirring at a speed of 1000 r / min, and stir for 35 min to dissolve the suspension stabilizer.
[0067] Step 3: After completing Step 2, add 5% retarder while stirring at a speed of 1000 r / min, and stir for 30 min to dissolve the retarder.
[0068] Step 4: After completing Step 3, add 1.5% defoamer while stirring at a speed of 1000 r / min, and stir for 30 min to dissolve the defoamer and obtain a large sample of water.
[0069] Step 5: Weigh 150% of the weighting material, add 1.5% of the composite sealing material, 2% of the silicate fiber, and 1% of the inorganic fiber to the weighting material, mix evenly, and obtain a large sample of ash.
[0070] Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, and stir and mix at a stirring speed of 5000 r / min to obtain the composite plugging pretreatment solution.
[0071] Example 6
[0072] A composite pre-sealant for sealing in this embodiment comprises the following components: 1000g water, 1% release agent, 0.5% suspension stabilizer, 6% retarder, 2% defoamer, 170% weighting material, 1.5% composite sealant material, 1% silicate fiber, and 1% inorganic fiber.
[0073] The preparation method of the composite plugging pre-fill fluid in this embodiment includes the following steps:
[0074] Step 1: Measure 1000g of water at 23℃, add 1% of the release agent to the water while stirring at 600r / min, and stir for 5min to dissolve the release agent.
[0075] Step 2: After completing Step 1, add 0.5% suspension stabilizer while stirring at a speed of 600 r / min, and stir for 10 min to dissolve the suspension stabilizer.
[0076] Step 3: After completing Step 2, add 6% retarder while stirring at a speed of 600 r / min, and stir for 10 min to dissolve the retarder.
[0077] Step 4: After completing Step 3, add 2% defoamer while stirring at a speed of 600 r / min, and stir for 10 min to dissolve the defoamer and obtain a large sample of water.
[0078] Step 5: Weigh 170% of the weighting material, add 1.5% of the composite sealing material, 1% of the silicate fiber, and 1% of the inorganic fiber to the weighting material, mix evenly, and obtain a large sample of ash.
[0079] Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, and stir and mix at a stirring speed of 4000 r / min to obtain the composite plugging pretreatment solution.
[0080] In the above embodiments, the unit of mass parts is kg. It is understood that mass parts can also be other mass units, such as t, g, mg, etc.
[0081] In the above embodiments and the formulation of the base slurry described below, the release agent is a cementing release agent purchased from Sichuan Hongsheng Petroleum Engineering Technology Service Co., Ltd., which is a high-temperature (120℃) solid cementing release agent with the code GL-2; the suspension stabilizer is an oil well cement suspension stabilizer purchased from Tianjin Baoen Petroleum Engineering Technology Co., Ltd., which is a high-temperature (≤120℃) oil well cement suspension stabilizer with the code TAS-153; the retarder is a high-temperature oil well cement retarder purchased from Sichuan Hongsheng Petroleum Engineering Technology Service Co., Ltd., which is a high-temperature (≤120℃) oil well cement retarder with the code BS200R; and the defoamer is purchased from Beijing Pusi. The oil well cement defoamer from Weiss Petroleum Technology Co., Ltd. is a liquid organosilicon-based defoamer, designated SUP12L. The weighting material is barite powder purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd., classified as premium grade. The composite plugging material is a composite plugging agent purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd., classified as Type II. The silicate fiber is a plugging agent silicate fiber purchased from Huixian Tianfeng Oilfield Additives Co., Ltd., classified as Type II. The inorganic fiber is chopped glass fiber reinforced concrete crack-resistant fiber, with a specification of 3mm-15mm.
[0082] The performance of the composite plugging pre-fluid in the above embodiments is evaluated, as detailed below.
[0083] The base slurry formulation is as follows: 1000g water, 1% release agent, 0.5% suspension stabilizer, 5% retarder, 1.5% defoamer, and 170% weighting material. The percentages of release agent, suspension stabilizer, retarder, defoamer, and weighting material correspond to the mass percentages of release agent, suspension stabilizer, retarder, defoamer, and weighting material relative to water, respectively.
[0084] The preparation method of the base slurry is as follows: Step 1, measure 1000g of water at a temperature of 23℃, add 1% release agent to the water while stirring at a speed of 600r / min, stir for 5min to dissolve the release agent;
[0085] Step 2: After completing Step 1, add 0.5% suspension stabilizer while stirring at a speed of 600 r / min, and stir for 10 min to dissolve the suspension stabilizer.
[0086] Step 3: After completing Step 2, add 5% retarder while stirring at a speed of 600 r / min, and stir for 10 min to dissolve the retarder.
[0087] Step 4: After completing Step 3, add 1.5% defoamer while stirring at a speed of 600 r / min, and stir for 10 min to dissolve the defoamer and obtain a large sample of water.
[0088] Step 5: Weigh 170% of the weighting material, add the water sample obtained in Step 4, and mix at a stirring speed of 4000 r / min to obtain the base slurry.
[0089] The fluidity of the base slurry and the composite plugging pre-filling fluid of the above embodiments was tested before and after curing. The test method was carried out in accordance with the test method of cement paste fluidity in the national standard GB_T8077~2012 "Test Method for Homogeneity of Concrete Admixtures". The test results are shown in Table 1. At the same time, the performance evaluation of the density difference was also carried out. The test method was carried out in accordance with the enterprise standard QSH CG0205—2023 "Technical Requirements for Cement Suspension Stabilizers for Oil Wells" of China Petroleum & Chemical Corporation. The test results are shown in Table 1.
[0090] Table 1 Basic properties of composite plugging pre-fill fluid and base slurry
[0091]
[0092] As shown in Table 1, the flowability of the composite plugging pre-filled fluid in Examples 2, 3, 4 and 5 meets the requirements, and the settling stability is good, which meets the construction requirements under different conditions.
[0093] To verify the anti-fouling properties of the composite pre-sealant used in Examples 2 to 5, cement slurry (density 1.90 g / cm³) was used. 3Anti-gas channeling cement slurry), drilling fluid (density 1.75 g / cm³) 3 Potassium-based polysulfonate water-based drilling fluid) and the composite plugging pre-fill fluid of Examples 2 to 5 were mixed according to volume percentage, and a compatibility test was conducted (the compatibility test mixing ratio was determined by volume ratio according to the industry standard SY / T 206544-2017 "Performance Requirements of Cement Slurry for Oil Wells", and the test method for the fluidity of cement paste in the national standard GB_T8077~2012 "Test Method for Homogeneity of Concrete Admixtures"). The test data obtained are shown in Tables 2 to 5.
[0094] Table 2. Anti-fouling performance test data of the composite plugging pre-filled fluid in Example 2.
[0095]
[0096] Table 3. Test data on the anti-fouling performance of the composite plugging pre-fill fluid in Example 3.
[0097]
[0098] Table 4. Anti-fouling performance test data of the composite plugging pre-fill fluid in Example 4.
[0099]
[0100] Table 5. Anti-fouling performance test data of the composite plugging pre-fluid in Example 5
[0101]
[0102] As shown in Tables 2 to 5, the composite pre-sealant of Examples 2 to 5 has good anti-pollution ability and can provide a safe construction time for the sealant operation.
[0103] To ensure construction safety, a comparative experiment on the static gel strength development of slurries with different proportions was conducted (the static gel strength development test method refers to Chapter 8 of standard GB / T 2019139-2012 "Test Methods for Cement in Oil Wells"). Static gel strength development tests were performed on slurries with different volume ratios of cement slurry, composite plugging pre-fluid, and drilling fluid. The test results are shown in Table 6.
[0104] Table 6 Comparison of Static Gelatinization Strength Development of Mixtures with Different Volume Ratios
[0105] Cement grout; Composite plugging pre-fill fluid; Drilling fluid Intensity build-up time (h) Cement stone strength (MPa) 10:0:0 6 29 10:0.5:0.5 10 25 10:1:1 11 13.8 8:1:1 15 11 6:1:1 24 3.5
[0106] Table 6 shows that when the volume ratio of cement slurry, composite plugging pre-fluid, and drilling fluid is 6:1:1, the mixture can develop strength, but the strength is relatively weak. This result indicates that the contact mixing of the composite plugging pre-fluid with drilling fluid and cement slurry has little impact on the strength development of the cement paste; the cement slurry can still develop strength when the mixture is in a certain proportion.
[0107] Evaluation of the sealing effect of composite pre-filled fluid: The performance of the sealing formula must meet the environmental requirements of the lost layer, have good matching with the size of the formation lost channel, and meet the temperature requirements of the formation in order to achieve a good sealing effect.
[0108] The self-regulating high-temperature and high-pressure dynamic plugging instrument for fractures is a novel plugging test instrument developed specifically for sealing fractured leaks. This instrument can simulate the temperature, pressure, and fluid flow patterns of the leaking formation during drilling, maximizing the simulation of wellbore conditions in leaking formations during drilling. Simulated fractures ranging from 0.1 to 10 mm are steplessly adjusted by an automatic control system to meet experimental requirements for simulating different fracture widths. Experiments are conducted to evaluate the structure, proportions, temperature resistance, and pressure resistance of plugging materials, and to study the plugging effects of different plugging agents on fractured leaking formations. This provides a complete and effective scientific basis for preventing leaks and properly handling leak accidents in drilling operations. The instrument used is the CDL-A-Ⅱ self-regulating high-temperature and high-pressure plugging instrument for fractures, jointly developed by Sinopec Petroleum Engineering Technology Research Institute Co., Ltd. and Hubei Chuanglian Petroleum Technology Co., Ltd.
[0109] 1) Sealing pressure: 25MPa, pressure control accuracy: 0.1%FS;
[0110] 2) Back pressure: 25MPa;
[0111] 3) Adjustable crack: crack width 0.1~10mm, control accuracy 0.1mm;
[0112] 4) Operating temperature range: room temperature to 200℃; temperature control accuracy: ±1℃.
[0113] 5) Vessel body: 1000mL capacity, made of 316L stainless steel;
[0114] 6) Leakage volume: 1500mL (one 1500mL container is provided);
[0115] 7) Rotor speed: 0~200r / min.
[0116] Table 7 Experimental data on the sealing effect of composite sealing pre-fluid.
[0117]
[0118]
[0119] As can be seen from the highest pressure bearing capacity data in Table 7, Examples 2, 3, 4, and 5 all have good sealing capabilities for cracks with widths of 3mm, 4mm, and 5mm, providing conditions for the subsequent interception and stabilization of cement slurry.
[0120] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the technical solutions of the present invention. Any technical solution that can be implemented based on the above embodiments without creative effort should be considered to fall within the scope of protection of the patent of the present invention.
Claims
1. A composite pre-sealant for plugging leaks, characterized in that, It comprises the following components: 1 part by mass of water, 1-3% of release agent, 0.5-2% of suspension stabilizer, 1-6% of retarder, 0.5-2% of defoamer, 70-170% of weighting material, 1.5-5% of composite sealing material, 1-5% of silicate fiber, and 1-1.5% of inorganic fiber. The percentages of release agent, suspension stabilizer, retarder, defoamer, weighting material, composite sealing material, silicate fiber, and inorganic fiber correspond to the mass percentages of release agent, suspension stabilizer, retarder, defoamer, weighting material, composite sealing material, silicate fiber, and inorganic fiber relative to water, respectively.
2. The composite pre-sealant for plugging leaks according to claim 1, characterized in that, It includes the following components: 1 part by weight of water, 1-3% of release agent, 0.5-2% of suspension stabilizer, 2-5% of retarder, 0.5-1.5% of defoamer, 90-150% of weighting material, 1.5-4% of composite sealing material, 2-4% of silicate fiber, and 1-1.5% of inorganic fiber.
3. The composite pre-sealant for plugging leaks according to claim 1, characterized in that, The separating agent is a cementing separator purchased from Sichuan Hongsheng Petroleum Engineering Technology Service Co., Ltd., and its specification is high-temperature solid, with the code GL-2; the suspension stabilizer is an oil well cement suspension stabilizer purchased from Tianjin Baoen Petroleum Engineering Technology Co., Ltd., and its specification is high-temperature type, with the code TAS-153; the retarder is a high-temperature oil well cement retarder purchased from Sichuan Hongsheng Petroleum Engineering Technology Service Co., Ltd., and its specification is high-temperature type, with the code BS200R; the defoamer is an oil well cement defoamer purchased from Beijing Pusiwei Petroleum Technology Co., Ltd. The defoaming agent for this oil well cement is a liquid organosilicon, with the code SUP12L; the weighting material is barite powder purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd., and the barite powder is of the premium grade; the composite plugging material is a composite plugging agent purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd., and the composite plugging agent is of the type II grade; the silicate fiber is a plugging agent silicate fiber purchased from Huixian Tianfeng Oilfield Additives Co., Ltd., and the plugging agent silicate fiber is of the type II grade; the inorganic fiber is chopped glass fiber reinforced concrete crack-resistant fiber, and the chopped glass fiber reinforced concrete crack-resistant fiber is of the 3mm-15mm grade.
4. A method for preparing the composite pre-sealing fluid according to claim 1, 2, or 3, characterized in that, Includes the following steps: Step 1: Add the separating agent to the water while stirring to dissolve the separating agent; Step 2: After completing Step 1, add the suspension stabilizer while stirring to dissolve the suspension stabilizer; Step 3: After completing Step 2, add the retarder while stirring to dissolve it. Step 4: After completing Step 3, add defoamer while stirring to dissolve the defoamer and obtain a large sample of water; Step 5: Add the composite sealing material, silicate fiber, and inorganic fiber to the weighting material, mix them evenly, and obtain a large sample of ash. Step 6: Add the large sample ash obtained in Step 5 to the large sample water obtained in Step 4, stir and mix to obtain the composite plugging pre-treatment solution.
5. The preparation method of the composite plugging pre-filling fluid according to claim 4, characterized in that, In step 1, the water temperature is 23~25℃, the stirring speed is 600~1000r / min, and the stirring time is at least 5min.
6. The method for preparing the composite pre-plugging fluid according to claim 4, characterized in that, In step 2, the stirring speed is 600~1000 r / min, and the stirring time is at least 5 min.
7. The preparation method of the composite plugging pre-fluid according to claim 4, characterized in that, In step 3, the stirring speed is 600~1000 r / min, and the stirring time is at least 2 min.
8. The method for preparing the composite pre-sealing fluid according to claim 4, characterized in that, In step 4, the stirring speed is 600~1000 r / min, and the stirring time is at least 2 min.
9. The preparation method of the composite plugging pre-filling fluid according to claim 4, characterized in that, In step 6, the stirring speed is 4000~5000 r / min.