CN111927322A - Method for preventing pressure supporting by using rigid particles in directional drilling - Google Patents
Method for preventing pressure supporting by using rigid particles in directional drilling Download PDFInfo
- Publication number
- CN111927322A CN111927322A CN202010972377.9A CN202010972377A CN111927322A CN 111927322 A CN111927322 A CN 111927322A CN 202010972377 A CN202010972377 A CN 202010972377A CN 111927322 A CN111927322 A CN 111927322A
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- pressure
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- vermiculite
- directional drilling
- drilling
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- 238000005553 drilling Methods 0.000 title claims abstract description 86
- 238000000034 method Methods 0.000 title claims abstract description 43
- 239000002245 particle Substances 0.000 title claims abstract description 38
- 230000008093 supporting effect Effects 0.000 title description 13
- 241000758789 Juglans Species 0.000 claims abstract description 29
- 235000009496 Juglans regia Nutrition 0.000 claims abstract description 29
- 229910052902 vermiculite Inorganic materials 0.000 claims abstract description 29
- 235000019354 vermiculite Nutrition 0.000 claims abstract description 29
- 239000010455 vermiculite Substances 0.000 claims abstract description 29
- 235000020234 walnut Nutrition 0.000 claims abstract description 29
- 239000012530 fluid Substances 0.000 claims abstract description 28
- 238000004140 cleaning Methods 0.000 claims abstract description 6
- 238000011010 flushing procedure Methods 0.000 claims abstract description 5
- 230000008569 process Effects 0.000 abstract description 14
- 230000000694 effects Effects 0.000 abstract description 9
- 230000006872 improvement Effects 0.000 abstract description 3
- 239000003795 chemical substances by application Substances 0.000 abstract description 2
- 230000008859 change Effects 0.000 description 5
- 230000009467 reduction Effects 0.000 description 4
- 230000002265 prevention Effects 0.000 description 3
- 230000007812 deficiency Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000011435 rock Substances 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000003209 petroleum derivative Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
- E21B7/04—Directional drilling
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
- E21B21/06—Arrangements for treating drilling fluids outside the borehole
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
- E21B21/08—Controlling or monitoring pressure or flow of drilling fluid, e.g. automatic filling of boreholes, automatic control of bottom pressure
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Mechanical Engineering (AREA)
- Earth Drilling (AREA)
Abstract
The invention provides a method for preventing pressure from being supported by rigid particles in directional drilling, which comprises the following steps: adding walnut shells and/or vermiculite with the granularity of less than 5mm into the drilling fluid according to the mass-volume ratio of 0.15-0.35%, controlling the adding speed to be not more than 25kg/10min, continuously observing the pressure of a pump flushing pump, and stopping operation and cleaning drill pipe filter paper if the pressure of the pump slowly rises; and (3) passing the returned drilling fluid through a vibrating screen to filter walnut shells and/or vermiculite which are not adhered to the well wall. The invention can utilize the matching relationship between the walnut shells and/or the vermiculite and the drilling fluid to realize the improvement of the friction mode between the drilling tool and the well wall in the directional drilling process (for example, the long horizontal section directional drilling), thereby achieving the effect of preventing the pressure holding; and the pressure-resisting agent is convenient to prepare on site, easy to operate, low in cost and good in pressure-resisting effect.
Description
Technical Field
The invention relates to the technical field of anti-pressure-holding technology of directional drilling in the process of exploration and development of petroleum and natural gas, in particular to a method for preventing pressure-holding by using rigid particles in directional drilling.
Background
The pressure relief refers to a phenomenon that the drilling pressure cannot be effectively transferred to a drill bit in the drilling process of a directional well, so that the drill bit cannot advance. The pressure relief is shown on the comprehensive logging instrument and the weight indicator that the position of the drill bit is unchanged, no drilling footage is carried out, the pump pressure is not increased, the pump is not blocked, and if the bit pressure is continuously increased, the pump is likely to be suddenly blocked. The pressure supporting phenomenon generally exists in horizontal wells, extended reach wells and highly deviated wells.
In order to solve the problem of pressure relief, various pressure relief (or friction and resistance reduction) prevention tools have been developed at home and abroad, including a pressure relief prevention tool based on a vibration principle, a friction reduction technology based on a sound wave pulse principle, a friction reducer based on a hydraulic cylinder working principle, a drilling tool based on particle pulse jet and the like. These anti-backup (or friction and drag reduction) tools (or methods) have been found to be effective in solving the backup problem that exists in directional wells. However, these tools are not well adapted to the downhole environment due to their own structure or pressure loss, so that it is difficult to achieve better anti-back-pressure effect.
At present, the common solution measures for improving the pressure supporting phenomenon are as follows:
1. and the well track is strictly controlled, and the drilling tool structure is optimized. In the directional well drilling, the well deviation section needs to be strictly controlled to well track, in addition, the structure of a drilling tool needs to be optimized, for example, the using number of drill collars is reduced, and meanwhile, a weighted drilling rod is adopted, so that the rigidity of the drilling tool is effectively reduced, the contact area of the drilling tool and a mud cake is reduced to reduce friction resistance, and in the drilling of a horizontal well and the like, the method of reversely installing the drilling tool can be adopted to reduce the support pressure after the well deviation reaches 45 degrees; the hole enlargement rate is ensured by adopting a back-reaming repeated operation mode at the parts with serious dog legs, so that the probability of key slot occurrence is reduced, and the key slot is prevented from being stuck with a drill.
2. The well bore is purified, and the performance of the drilling fluid is improved. During drilling, the rock debris is deposited on the well wall to make the drill stem obtain larger friction resistance, so that the well hole purification and the drilling fluid can effectively reduce the pressure supporting, during the drilling operation, the short tripping operation can be carried out once after the drilling is carried out for a certain displacement, the deposited rock debris can return to the ground along with the drilling fluid, meanwhile, the returned drilling fluid passes through a solid control device such as a centrifuge and a vibrating screen, the contents of harmful solid phase, poor soil and the like in the drilling fluid are reduced, and the purpose of reducing the pressure supporting is effectively achieved by effectively avoiding the deficiency and thickness of mud cakes. In addition, the performance of the drilling fluid, such as lubricating performance and sand carrying capacity, can be improved, and the effect of reducing the pressure is good.
3. And installing an anti-backing pressure tool. The reason for the occurrence of the pressure in the directional well is comprehensively analyzed, mainly friction resistance causes the pressure supporting phenomenon, and particularly the pressure supporting phenomenon is more obvious in sliding drilling, so that a pressure supporting prevention tool is arranged in a drill string, the friction resistance can be effectively overcome through vibration or mechanical resistance reduction, the drill string is continuously extended to ensure the normal transmission of the drill pressure, and the pressure supporting is effectively reduced.
Disclosure of Invention
The present invention aims to address at least one of the above-mentioned deficiencies of the prior art. For example, it is an object of the present invention to provide a method for preventing back pressure by adding rigid particles to a directional drilling fluid.
In order to achieve the above object, the present invention provides a method for preventing back pressure using rigid particles in directional drilling, the method comprising: adding walnut shells and/or vermiculite with the granularity of less than 5mm into the drilling fluid according to the mass-volume ratio of 0.15-0.35%, controlling the adding speed to be not more than 25kg/10min, continuously observing the pressure of a pump flushing pump, and stopping operation and cleaning drill pipe filter paper if the pressure of the pump slowly rises; and (3) passing the returned drilling fluid through a vibrating screen to filter walnut shells and/or vermiculite which are not adhered to the well wall.
In an exemplary embodiment of the invention, the walnut shells and/or vermiculite may have a particle size of 2.5mm to 4.5 mm.
In an exemplary embodiment of the invention, the method may further control the addition rate of the walnut shells and/or vermiculite at the beginning of the addition stage to be 25kg per 20min to 30 min. In addition, whether the pump flushing and the pump pressure are normal or not can be observed in the initial adding stage, and if the pump pressure is normal, the adding speed of the walnut shells and/or the vermiculite is increased.
In an exemplary embodiment of the present invention, the mass-to-volume ratio may be 0.2% to 0.3%.
Compared with the prior art, the invention has the beneficial effects that: the friction mode between a drilling tool and a well wall in the directional drilling process (such as long horizontal section directional drilling) can be improved by utilizing the matching relationship between the walnut shells and/or the vermiculite and the drilling fluid, so that the effect of preventing the pressure holding is further achieved; and the pressure-resisting agent is convenient to prepare on site, easy to operate, low in cost and good in pressure-resisting effect.
Drawings
FIG. 1 shows a schematic flow diagram of an exemplary embodiment of a method of using rigid particles to prevent back pressure in directional drilling of the present invention.
Detailed Description
Hereinafter, the method of using rigid particles for resisting back pressure in directional drilling according to the present invention will be described in detail with reference to exemplary embodiments.
In summary, the method of the invention is directed to the directional drilling (for example, long horizontal section directional drilling) process, mainly depends on adding walnut shells and/or vermiculite as rigid particles into the drilling fluid, and controls the appropriate adding amount and the appropriate adding speed while continuously observing the change condition of the pump pressure in the adding process, thereby realizing the improvement of the friction mode between the drilling tool and the well wall and achieving the purpose of preventing the pressure holding.
In one exemplary embodiment of the present invention, as shown in fig. 1, the method of using rigid particles for anti-back pressure in directional drilling may be implemented by the following steps:
(1) walnut shells and/or vermiculite with the granularity of less than 5mm are added into the drilling fluid according to the mass-volume ratio of 0.15-0.35%, and the adding speed is controlled not to exceed 25kg/10 min; and meanwhile, continuously observing the pump pressure of the pump, stopping the operation and cleaning the drill pipe filter paper if the pump pressure slowly rises (for example, the rising speed of the pump pressure exceeds 0.5MPa/min), and otherwise, continuously adding the walnut shells and/or the vermiculite. Here, the particle size of the walnut shells and/or the vermiculite may preferably be 2.5mm to 4.5 mm. The mass volume ratio of the walnut shells and/or the vermiculite in the drilling fluid is preferably 0.2-0.3%.
(2) And (3) passing the returned drilling fluid through a vibrating screen to filter walnut shells and/or vermiculite which are not adhered to the well wall.
Through field tests, the method of the exemplary embodiment can greatly improve the pressure supporting problem in the process of directional drilling of a long horizontal section (for example, the length of the horizontal section can be 1000-3000 m), the used well depth can reach 6000 meters at the maximum, and the used temperature can reach 150 ℃ at the maximum.
In another exemplary embodiment of the invention, the method not only adds the walnut shells and/or the vermiculite with the particle size of less than 5mm into the drilling fluid according to the mass-volume ratio of 0.15-0.35%, and controls the adding speed not to exceed 25kg/10min, but also controls the adding speed of the walnut shells and/or the vermiculite in the initial adding stage (for example, the first 60min of the adding process) to be 25kg per 20 min-30 min; and meanwhile, continuously observing whether the pump impact and the pump pressure are normal, if the pump pressure is normal, increasing the adding speed of the walnut shells and/or the vermiculite but not exceeding 25kg/10min, if the pump pressure slowly rises, stopping the operation and cleaning the drill pipe filter paper, and otherwise, continuously adding the walnut shells and/or the vermiculite. The expression "whether the pump stroke and the pump pressure are normal" means that the pump pressure value is constant when the pump stroke number of the slurry pump is constant during field drilling operation, and this means that the pump stroke and the pump pressure are normal. If the pump stroke number is constant, the pump pressure value is increased or decreased by not more than 0.5MPa/min, namely the pump pressure is considered to be normal.
In general, the method of the invention can change the conventional drilling fluid lubrication thought, properly add rigid particles into the drilling fluid, change the contact state of the drilling tool and the well wall in the construction operation process, and effectively utilize the characteristics of the walnut shells and/or the vermiculite to change the surface-surface contact of the drilling tool and the well wall into surface-point contact with the strength, the friction resistance and the like suitable for directional drilling (including horizontal drilling), so as to achieve the purposes of reducing the friction resistance and improving the pressure of the drilling tool.
In yet another exemplary embodiment of the present invention, a method of using rigid particles for anti-backup pressure in directional drilling is achieved by:
1. the walnut shells and/or the vermiculite are used as rigid particles, the rigid particles are uniformly screened by a filter screen, the aperture of the filter screen is 5mm, irregular particles with larger particle sizes are screened out, and the situation that the filter paper of a drill rod and a directional instrument are blocked after the particles are added is avoided. Keeping rigid particles with the diameter less than 5mm for standby.
2. In the field directional drilling process, rigid particles are uniformly added into the drilling fluid through a special material weighting pump for the drilling fluid, a stirrer of a circulating tank is completely opened during the adding, the adding speed is controlled to be uniformly added at the speed of adding one bag (25kg) every 20-30 minutes, the adding speed can be properly accelerated after the observation of normal field pump flushing, pump pressure and the like, but the speed cannot exceed 10 minutes, and one bag (25kg) is added.
3. The drilling fluid has better effect when the integral concentration (mass volume ratio) of the rigid particles in the drilling fluid is 0.2-0.3%.
4. And continuously observing whether the pump pressure of the pump punch pump is abnormal or not in the process of adding the rigid particles, and stopping the operation and timely cleaning the filter paper of the drill rod if the pump pressure slowly rises.
5. The returned drilling fluid needs to pass through a field vibrating screen, and rigid particles which are not adhered to the well wall are removed.
Through a plurality of field tests, the method can greatly improve the pressure supporting problem in the orientation process of the long horizontal section, the using well depth reaches 6000 meters, and the using temperature can reach as high as 150 ℃.
The rigid particles used in this exemplary embodiment are as follows:
(1) the walnut shells with coarse grains are used separately. The particle size is preferably in the range of 3mm to 5 mm.
(2) Coarse-grained vermiculite was used alone. The particle size is preferably in the range of 3mm to 5 mm.
(3) Mixing the walnut shells with vermiculite. The proportion can be adjusted at will, and the particle size range is controlled to be optimal between 3mm and 5 mm.
The method of the exemplary embodiment applies 8 wells in a directional well test in which the open hole length of the basin area of the Xinjiang platform exceeds 3000 meters, the average drilling speed is improved by 121.54%, and the travel drilling speed is improved by 112.53%; the accumulated saved drilling period is 66.48 days, and the average saved drilling period is 8.31 days; and the good anti-pressure-supporting effect is embodied.
In conclusion, aiming at the directional drilling process (such as long horizontal section directional drilling), the method disclosed by the invention can realize the improvement of the friction mode between a drilling tool and the well wall by adding walnut shells and/or vermiculite into the drilling fluid as rigid particles and controlling the appropriate adding amount and the appropriate adding speed and time and continuously observing the change condition of the pump pressure in the adding process, thereby achieving the effect of preventing the pressure holding; the method has the advantages of convenient field preparation, easy operation, low cost and good anti-pressure supporting effect.
Although the present invention has been described above in connection with the exemplary embodiments and the accompanying drawings, it will be apparent to those of ordinary skill in the art that various modifications may be made to the above-described embodiments without departing from the spirit and scope of the claims.
Claims (6)
1. A method of using rigid particles to resist back pressure in directional drilling, the method comprising the steps of:
adding walnut shells and/or vermiculite with the granularity of less than 5mm into the drilling fluid according to the mass-volume ratio of 0.15-0.35%, controlling the adding speed to be not more than 25kg/10min, continuously observing the pressure of a pump flushing pump, and stopping operation and cleaning drill pipe filter paper if the pressure of the pump slowly rises;
and (3) passing the returned drilling fluid through a vibrating screen to filter walnut shells and/or vermiculite which are not adhered to the well wall.
2. The method for using rigid particles to prevent back pressure in directional drilling according to claim 1, wherein the walnut shells and/or vermiculite have a particle size of 2.5mm to 4.5 mm.
3. The method for preventing the pressure of the fixed particles during the directional drilling according to the claim 1, wherein the adding speed of the walnut shells and/or the vermiculite at the beginning of the adding stage is controlled to be 25kg per 20 min-30 min.
4. The method for preventing the pressure of the rigid particles during the directional drilling according to claim 3, wherein the adding starting stage is also observed whether the pump impact and the pump pressure are normal, and if the pump pressure is normal, the adding speed of the walnut shells and/or the vermiculite is increased.
5. The method for preventing back pressure by using the rigid particles in directional drilling according to claim 1, wherein the mass-to-volume ratio is 0.2-0.3%.
6. The method for preventing the back pressure of the rigid particles in the directional drilling according to claim 1, wherein the directional drilling is a directional drilling stage with the horizontal section length exceeding 1000 m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010972377.9A CN111927322A (en) | 2020-09-16 | 2020-09-16 | Method for preventing pressure supporting by using rigid particles in directional drilling |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010972377.9A CN111927322A (en) | 2020-09-16 | 2020-09-16 | Method for preventing pressure supporting by using rigid particles in directional drilling |
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| CN111927322A true CN111927322A (en) | 2020-11-13 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7343985B1 (en) * | 2007-02-26 | 2008-03-18 | Harold Gregg | Bit balling treatment |
| CN101935519A (en) * | 2010-08-09 | 2011-01-05 | 中联煤层气国家工程研究中心有限责任公司 | Drilling fluid and preparation method thereof |
| CN103555300A (en) * | 2013-11-15 | 2014-02-05 | 西安石油大学 | Method for preparing environment-friendly viscosity and filtrate reducer for drilling fluid through walnut peels and application of viscosity and filtrate reducer |
| CN104610943A (en) * | 2015-01-22 | 2015-05-13 | 海隆石油技术服务有限公司 | Water-based nano drilling fluid and preparation method thereof |
-
2020
- 2020-09-16 CN CN202010972377.9A patent/CN111927322A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7343985B1 (en) * | 2007-02-26 | 2008-03-18 | Harold Gregg | Bit balling treatment |
| CN101935519A (en) * | 2010-08-09 | 2011-01-05 | 中联煤层气国家工程研究中心有限责任公司 | Drilling fluid and preparation method thereof |
| CN103555300A (en) * | 2013-11-15 | 2014-02-05 | 西安石油大学 | Method for preparing environment-friendly viscosity and filtrate reducer for drilling fluid through walnut peels and application of viscosity and filtrate reducer |
| CN104610943A (en) * | 2015-01-22 | 2015-05-13 | 海隆石油技术服务有限公司 | Water-based nano drilling fluid and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 张军等: "承压堵漏技术在定向大斜度深井中的应用", 《天然气工业》 * |
| 舒义勇等: "哈拉哈塘区块标准井防阻卡钻井液技术", 《石油钻采工艺》 * |
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Application publication date: 20201113 |
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