CN203097765U - Auxiliary cutting-carrying tool for coal-bed methane exploiting air inflation underbalanced drilling multilateral well - Google Patents
Auxiliary cutting-carrying tool for coal-bed methane exploiting air inflation underbalanced drilling multilateral well Download PDFInfo
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- CN203097765U CN203097765U CN 201220749256 CN201220749256U CN203097765U CN 203097765 U CN203097765 U CN 203097765U CN 201220749256 CN201220749256 CN 201220749256 CN 201220749256 U CN201220749256 U CN 201220749256U CN 203097765 U CN203097765 U CN 203097765U
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Abstract
The utility model discloses an auxiliary cutting-carrying tool for a coal-bed methane exploiting air inflation underbalanced drilling multilateral well, and belongs to the technical filed of petroleum, natural gas, and geological well drilling. The cutting-carrying tool comprises a body which is formed integrally. The cutting-carrying tool body comprises a shoulder haft, a transition diversion slope, a middle neck, an inlet diversion slope, a spiral transporting structure, an outlet diversion slope, and a connector, wherein the spiral transporting structure is arranged on the middle neck portion. Through the spiral transporting structure, spiral disorderly-state strong-rotational-flow can be generated to flow, and in a coal-bed methane exploiting well section annulus, liquid substrate circulating medium rotational-flow energy is enhanced, and cutting-carrying capacity of the coal-bed methane exploiting well section annulus is improved. An arc spiral prism can be used for enabling rock debris blocks in upward movement and inside the annulus to be crashed into small rock debris particles, erosive abrasion to the surface of a drilling rod from the large-size rock debris particles is reduced, and the service life of the drilling rod is prolonged. Through an arc spiral groove, the transporting performance of rock debris in the annulus can be improved, and damage to coal reservoirs is lowered.
Description
Technical field
The utility model relates to oil, natural gas and geological drilling field, and particularly a kind of coal-bed gas exploitation inflation underbalance that is used for is bored the auxiliary rock instrument of taking of Multilateral Wells.
Background technology
Coal bed gas claims " gas " again, and its main component is a methane, and calorific value and natural gas are suitable, can mix defeated using with natural gas, and very clean after the burning, produces any waste gas hardly, is first-class industry, chemical industry, generating and resident living fuel.
The inflation under-balanced drilling technology is to reduce the coal seam reservoirs injury in the present coal bed gas drilling well, and one of measure that the protection coal seam reservoirs is the most frequently used can improve low permeability reservoir coal bed gas recovery ratio effectively by combining with the multi-branched horizontal well drilling technology.
In realizing process of the present utility model, the inventor finds that there is following problem at least in prior art:
One, coal seam reservoirs injury is one of decisive factor that influence the cbm development success rate, and the desorb, diffusion, migration and the later stage that directly have influence on coal bed gas arrange and adopt.During water-base drilling fluid technology drilling coal bed gas, adopt the raising drilling fluid density to creep into usually, but easily cause the coal seam to pollute and injury to guarantee safety.
Two, bore in the Multilateral Wells operation in the inflation underbalance, because of the effect of landwaste self gravitation, make uneven being suspended in the drilling fluid of annular space section landwaste of drilling rod body correspondence, and sedimentation trend is arranged, cause the interior large rock-carrying ability of annular space relatively poor, have a strong impact on coal bed gas drilling well timeliness and drilling cost.
Three, present stage, the design and use special tool is the new approaches that realize improving coal bed gas drilling well timeliness and drilling cost on the injury basis that keeps coal seam reservoirs wellbore stability, reduction coal seam reservoirs.At present, relate to many new-type instruments and instrument in the external coal bed gas inflation underbalance branch hole drilling process, for example be used for the electromagnetic measurement device that two wells are communicated with, undersized geosteering tool and efficient drag reduction pipe nipple etc., yet, for suspension of cuttings in drilling fluid, cause the relatively poor problem of large rock-carrying ability in the annular space, present stage does not have good solution, especially bore in the Multilateral Wells operation in the inflation underbalance, the rock instrument of taking of effectively removing landwaste in the annular space also is in blank at present, does not have product to come out.
Summary of the invention
In order to solve prior art problems, the utility model embodiment provides a kind of coal-bed gas exploitation inflation underbalance that is used for to bore the auxiliary rock instrument of taking of Multilateral Wells.By strengthening liquid base circulatory mediator eddy flow kinetic energy, effectively improve the large rock-carrying ability of coal-bed gas exploitation Multilateral Wells section annular space, improve coal bed gas drilling well timeliness, reduce drilling cost.Described technical scheme is as follows:
A kind of coal-bed gas exploitation inflation underbalance that is used for is bored the auxiliary rock instrument of taking of Multilateral Wells, describedly take the body that the rock instrument comprises global formation, describedly take that the rock tool body comprises that shoulder axle, domatic, the middle neck of transition water conservancy diversion, entrance guiding are domatic, spiral migration structure, export the domatic and joint of water conservancy diversion; Neck position during described spiral migration structure is arranged on.
Particularly, the described rock tool body of taking is a hollow cylinder, external diameter is a reducing, form two ends shoulder axle and middle neck, described two ends shoulder axle is a benchmark and symmetrically, an end is inlet shoulder axle with the vertical center line of neck in described, and the other end is outlet shoulder axle, the center of described inlet shoulder axle and described outlet shoulder axle and the center of described middle neck are on same horizontal center line, and the outer end of described inlet shoulder axle is provided with described joint; To be provided with described transition water conservancy diversion domatic for the neck transition position during described inlet shoulder axle and outlet shoulder were axially described, with described in the neck external diameter seamlessly transit.
Further, the outside dimension 2-6mm of the outside dimension of axle greater than neck in described takeed at described two ends.
Particularly, the axial length of described spiral migration structure occupies 1/2 to 2/3 of described middle neck axial length, and described middle neck residue axial length is symmetrical distribution in described spiral migration structure both sides.
Particularly, described spiral migration structure comprises circular arc type spiral prism, circular arc type helicla flute at least; Described circular arc type spiral is prismatic and described circular arc type helicla flute is circumferentially upward wide and be equidistant type distributes, and the prismatic angle of slope γ of circular arc type spiral is 40～60 °; Described circular arc type spiral prism is three to seven, be evenly distributed on the described spiral migration structure by circumference, it is domatic that the initiating terminal of described circular arc type spiral prism is provided with described entrance guiding, and it is domatic that clearing end is provided with described outlet water conservancy diversion, and all the external diameter with described middle neck seamlessly transits; Described circular arc type spiral fluted bottom land is the external diameter of described middle neck.
Further, the outside dimension of described circular arc type spiral prism is greater than the outside dimension 3～10mm of two ends shoulder axle.
Further, the domatic and described outlet water conservancy diversion of domatic, the described entrance guiding of described transition water conservancy diversion is domatic is inclined-plane or arc surface.
The beneficial effect that the technical scheme that the utility model embodiment provides is brought is:
1, the utility model embodiment flows by producing the strong eddy flow of the disorderly attitude of helical form at the circular arc type spiral prism of circumferentially equidistantly arranging of taking the spiral migration structure that is provided with on the rock tool body and circular arc type helicla flute, in coal-bed gas exploitation Multilateral Wells section annular space, strengthen liquid base circulatory mediator eddy flow kinetic energy, improved the large rock-carrying ability of coal-bed gas exploitation Multilateral Wells section annular space.
2, with the rotation of drilling rod, the landwaste group that returns in the annular space can be broken into tiny cutting grain by circular arc type spiral prism, reduce of the erosive wear of bulky grain landwaste to the drilling rod surface, thereby the application life of having improved drilling rod; By the supreme annular space high velocity of landwaste of annular space low speed migration under the circular arc type helicla flute portability Multilateral Wells section, improved landwaste migration performance in the annular space, landwaste in the annular space of effectively migrating reduces the coal seam reservoirs injury, has significantly improved low permeability reservoir coal bed gas recovery ratio.
Description of drawings
In order to be illustrated more clearly in the technical scheme among the utility model embodiment, the accompanying drawing of required use is done to introduce simply in will describing embodiment below, apparently, accompanying drawing in describing below only is embodiment more of the present utility model, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is that the coal-bed gas exploitation inflation underbalance that is used for that the utility model embodiment provides is bored the auxiliary rock tool construction schematic diagram of taking of Multilateral Wells;
Fig. 2 be the utility model embodiment provide take the rock tool work time coal-bed gas exploitation Multilateral Wells section annular space in the axial schematic diagram of landwaste migration mechanism;
Fig. 3 is the mechanism cross sectional representation that the circular arc type scroll groove of the rock instrument of taking that provides of the utility model embodiment carries down the supreme annular space of annular space landwaste.
Each symbolic representation implication is as follows among the figure:
1 shoulder axle, 1.1 inlet shoulder axles, 1.2 outlet shoulder axles,
2 transition water conservancy diversion are domatic, neck in 3, and 4 entrance guidings are domatic,
5 spirals migration structure, 5.1 circular arc type spiral prisms, 5.2 circular arc type helicla flutes,
6 outlet water conservancy diversion are domatic, 7 joints;
The last borehole wall of A, the borehole wall under the B, C cutting grain low speed flow region, the disorderly attitude flow region of D cutting grain high-speed screw, annular space low regime under the E, the last annular space high velocity of F, J well;
The Ca axial load, M moment of torsion, γ angle of slope.
Arrow is that cutting grain flows to (promptly by cutting grain enter the mouth the direction of cutting grain outlet).
The specific embodiment
For making the purpose of this utility model, technical scheme and advantage clearer, the utility model embodiment is described in further detail below in conjunction with accompanying drawing.
Referring to Fig. 1, shown in Figure 2, the utility model embodiment provides a kind of coal-bed gas exploitation inflation underbalance that is used for to bore the auxiliary rock instrument of taking of Multilateral Wells, employing is provided with spiral migration structure on tool body, strengthened liquid base circulatory mediator eddy flow kinetic energy, effectively remove landwaste in the annular space, improve low permeability reservoir coal bed gas recovery ratio.The described rock tool body of taking mainly comprises: parts such as shoulder axle 1, transition water conservancy diversion are domatic 2, middle neck 3, entrance guiding are domatic 4, spiral migration structure 5, outlet water conservancy diversion are domatic 6, joint 7, and material is an alloy steel, the whole manufacturing is shaped to one.
Particularly, as preferably, the described rock tool body of taking is a hollow cylinder, its external diameter is a reducing, form big shoulder axle 1 and the little middle neck 3 of middle part diameter of two ends diameter, the shoulder axle 1 at described two ends is a benchmark and symmetrically with the vertical center line of neck 3 in described, one end is inlet shoulder axle 1.1, the other end is outlet shoulder axle 1.2, and the center of inlet shoulder axle 1.1 and outlet shoulder axle 1.2 and the center of middle neck 3 are on same horizontal center line, the outer end of described inlet shoulder axle 1.1 is provided with joint 7, in order to connect drilling rod; It is domatic 2 that described inlet shoulder axle 1.1 and outlet shoulder axle 1.2 are provided with the transition water conservancy diversion to middle neck 3 transition positions, seamlessly transits with the external diameter of middle neck 3; The centre of neck 3 is provided with spiral migration structure 5 in described.
Further, the outside dimension of described two ends shoulder axle 1 is greater than the outside dimension of middle neck 3, approximately greater than 2-6mm; The axial length of described spiral migration structure 5 occupies 1/2 to 2/3 of middle neck 3 axial lengths, and middle neck 3 residue axial lengths 1/2 to 1/3 are symmetrical distribution in spiral migration structure 5 both sides.
Particularly, as preferably, described spiral migration structure 5 comprises circular arc type spiral prism 5.1, circular arc type helicla flute 5.2 at least; Described circular arc type spiral prismatic 5.1 is circumferentially gone up wide and is equidistant type with circular arc type helicla flute 5.2 and distributes, and the prismatic 5.1 angle of slope γ of circular arc type spiral are 40～60 °; Described circular arc type spiral prism 5.1 is three to seven, be evenly distributed on the spiral migration structure 5 by circumference, it is domatic 4 that the initiating terminal of described circular arc type spiral prism 5.1 is provided with entrance guiding, and it is domatic 6 that clearing end is provided with the outlet water conservancy diversion, and all the external diameter with middle neck 3 seamlessly transits; The bottom land of described circular arc type helicla flute 5.2 is the external diameter of described middle neck 3; The external diameter of described circular arc type spiral prism 5.1 is than the about 3～10mm of outside dimension of two ends shoulder axle 1; Described spiral migration structure 5 can produce the strong eddy flow of the disorderly attitude of helical form and flow, and has improved large rock-carrying ability, effectively protects reservoir, reduces coal seam reservoirs and caves in.
Further, the surface profile that described transition water conservancy diversion is domatic 2, entrance guiding domatic 4 and outlet water conservancy diversion domatic 6 all adopt inclined-plane or arc surface, end surface thickness is zero, no boss, help will entering the mouth in turn shoulder axle 1.1, middle neck 3, circular arc type spiral prism 5.1, middle neck 3, outlet shoulder axle 1.2 joints seamlessly transits, and returns landwaste in the reduction through the auxiliary kinetic energy loss of taking before and after the rock instrument.
Referring to Fig. 2, shown in Figure 3, the operating principle of the utility model embodiment: bore in the Multilateral Wells operation in the inflation underbalance, every 2～3 drilling rods an auxiliary rock instrument of taking is installed in the net horizontal section, between borehole wall A on the well J and following borehole wall B, in the coal-bed gas exploitation Multilateral Wells section annular space, cutting grain enters the disorderly attitude flow region of cutting grain high-speed screw D through cutting grain low speed flow region C in the direction of arrows, at this moment, circular arc type spiral prismatic 5.1 that described spiral migration structure 5 is circumferentially equidistantly arranged and circular arc type helicla flute 5.2 can produce the strong eddy flow of the disorderly attitude of helical form and flow, this is auxiliary takes 3～5 times of annular space section eddy flow kinetic energy that the pairing annular space section of rock instrument eddy flow kinetic energy is about drilling rod body correspondence, strengthen liquid base circulatory mediator eddy flow kinetic energy, improved the large rock-carrying ability of coal-bed gas exploitation Multilateral Wells section annular space.
Under the rotation of drilling rod drives, take the rock instrument and carrying axial load Ca and moment of torsion M, described spiral migration structure 5 will be descended the landwaste in the annular space low regime E to carry by the migration of circular arc type helicla flute 5.2 low speed on the one hand and return supreme annular space high velocity F, by circular arc type spiral prism 5.1 landwaste group is broken into tiny cutting grain simultaneously, reduce of the erosive wear of bulky grain landwaste, improve the application life of drilling rod the drilling rod surface; Carry the landwaste that annular space low regime E migrates under the Multilateral Wells section by circular arc type helicla flute 5.2 on the other hand and migrate at a high speed, improved landwaste migration performance in the annular space through last annular space high velocity F.
And, when the coal bed gas operation makes a trip, have the entrance guiding that seamlessly transits inclined-plane or arc surface domatic 4 and outlet water conservancy diversion domatic 6 has good guiding function, that has improved drilling tool passes through performance and operating efficiency.
In addition, the advantage that the utility model embodiment also has is: auxiliaryly take the rock instrument owing to install one every 2～3 drilling rods in net horizontal section, significantly improve rate of penetration, shorten drilling period, improve the economy of China's cbm development.And the described rock tool body size of taking designs according to the corresponding drilling rod size of American Petroleum Institute (API) (API) fully, during use joint 7 is directly connected on the drilling rod by screw thread, and easy to operate, applicability is strong, and is safe to use.
The above only is preferred embodiment of the present utility model, and is in order to restriction the utility model, not all within spirit of the present utility model and principle, any modification of being done, is equal to replacement, improvement etc., all should be included within the protection domain of the present utility model.
Claims (7)
1. one kind is used for the auxiliary rock instrument of taking that coal-bed gas exploitation is inflated underbalance brill Multilateral Wells, it is characterized in that, describedly take the body that the rock instrument comprises global formation, the described rock tool body of taking comprises shoulder axle (1), a transition water conservancy diversion domatic (2), middle neck (3), entrance guiding domatic (4), spiral migration structure (5), outlet water conservancy diversion domatic (6) and joint (7); Described spiral migration structure (5) is arranged on middle neck (3) position.
2. the coal-bed gas exploitation inflation underbalance that is used for according to claim 1 is bored the auxiliary rock instrument of taking of Multilateral Wells, it is characterized in that, the described rock tool body of taking is a hollow cylinder, external diameter is a reducing, form two ends shoulder axle (1) and middle neck (3), described two ends shoulder axles (1) are benchmark and symmetrically with the vertical center line of neck (3) in described, one end is inlet shoulder axle (1.1), the other end is outlet shoulder axle (1.2), the center of the center of described inlet shoulder axle (1.1) and described outlet shoulder axle (1.2) and described middle neck (3) is on same horizontal center line, and the outer end of described inlet shoulder axle (1.1) is provided with described joint (7); Described inlet takes on axle (1.1) and outlet shoulder axle (1.2) neck (a 3) transition position in described is provided with described transition water conservancy diversion domatic (2), seamlessly transits with described middle neck (3) external diameter.
3. the coal-bed gas exploitation inflation underbalance that is used for according to claim 2 is bored the auxiliary rock instrument of taking of Multilateral Wells, it is characterized in that the outside dimension of described two ends shoulder axles (1) is greater than the outside dimension 2-6mm of neck (3) in described.
4. the coal-bed gas exploitation inflation underbalance that is used for according to claim 1 is bored the auxiliary rock instrument of taking of Multilateral Wells, it is characterized in that, the axial length of described spiral migration structure (5) occupies 1/2 to 2/3 of described middle neck (3) axial length, and described middle neck (3) residue axial length is symmetrical distribution in described spiral migration structure (5) both sides.
5. the coal-bed gas exploitation inflation underbalance that is used for according to claim 4 is bored the auxiliary rock instrument of taking of Multilateral Wells, it is characterized in that described spiral migration structure (5) comprises circular arc type spiral prism (5.1), circular arc type helicla flute (5.2) at least; Described circular arc type spiral prism (5.1) is circumferentially gone up wide with described circular arc type helicla flute (5.2) and is equidistant type and distributes, and circular arc type spiral prism (5.1) angle of slope γ is 40～60 °; Described circular arc type spiral prism (5.1) is three to seven, be evenly distributed on the described spiral migration structure (5) by circumference, the initiating terminal of described circular arc type spiral prism (5.1) is provided with described entrance guiding domatic (4), clearing end is provided with described outlet water conservancy diversion domatic (6), and all the external diameter with described middle neck (3) seamlessly transits; The bottom land of described circular arc type helicla flute (5.2) is the external diameter of described middle neck (3).
6. the coal-bed gas exploitation inflation underbalance that is used for according to claim 5 is bored the auxiliary rock instrument of taking of Multilateral Wells, it is characterized in that the outside dimension of described circular arc type spiral prism (5.1) is greater than the outside dimension 3～10mm of two ends shoulder axles (1).
7. bore the auxiliary rock instrument of taking of Multilateral Wells according to the described coal-bed gas exploitation inflation underbalance that is used for of each claim of claim 1-6, it is characterized in that described transition water conservancy diversion domatic (2), described entrance guiding domatic (4) and described outlet water conservancy diversion domatic (6) are inclined-plane or arc surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220749256 CN203097765U (en) | 2012-12-31 | 2012-12-31 | Auxiliary cutting-carrying tool for coal-bed methane exploiting air inflation underbalanced drilling multilateral well |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220749256 CN203097765U (en) | 2012-12-31 | 2012-12-31 | Auxiliary cutting-carrying tool for coal-bed methane exploiting air inflation underbalanced drilling multilateral well |
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| Publication Number | Publication Date |
|---|---|
| CN203097765U true CN203097765U (en) | 2013-07-31 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220749256 Withdrawn - After Issue CN203097765U (en) | 2012-12-31 | 2012-12-31 | Auxiliary cutting-carrying tool for coal-bed methane exploiting air inflation underbalanced drilling multilateral well |
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| CN (1) | CN203097765U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103912225A (en) * | 2012-12-31 | 2014-07-09 | 中国石油天然气集团公司 | Auxiliary cutting carrying tool for coal seam gas extraction gas-filled underbalanced drilling of multilateral wells |
| CN104806184A (en) * | 2015-05-11 | 2015-07-29 | 中国石油大学(北京) | Drilling jet flow mill rock crushing short joint of horizontal well |
| CN109882098A (en) * | 2019-03-15 | 2019-06-14 | 中国石油集团工程技术研究院有限公司 | Rock short tube is taken in spiral decompression |
-
2012
- 2012-12-31 CN CN 201220749256 patent/CN203097765U/en not_active Withdrawn - After Issue
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103912225A (en) * | 2012-12-31 | 2014-07-09 | 中国石油天然气集团公司 | Auxiliary cutting carrying tool for coal seam gas extraction gas-filled underbalanced drilling of multilateral wells |
| CN103912225B (en) * | 2012-12-31 | 2016-06-08 | 中国石油天然气集团公司 | The auxiliary inflating underbalance brill Multilateral Wells for coal-bed gas exploitation takes rock instrument |
| CN104806184A (en) * | 2015-05-11 | 2015-07-29 | 中国石油大学(北京) | Drilling jet flow mill rock crushing short joint of horizontal well |
| CN109882098A (en) * | 2019-03-15 | 2019-06-14 | 中国石油集团工程技术研究院有限公司 | Rock short tube is taken in spiral decompression |
| CN109882098B (en) * | 2019-03-15 | 2024-04-02 | 中国石油天然气集团有限公司 | Spiral depressurization rock-carrying short pipe |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20130731 Effective date of abandoning: 20160608 |
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| C25 | Abandonment of patent right or utility model to avoid double patenting |