CN108331570A - A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio - Google Patents

A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio Download PDF

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Publication number
CN108331570A
CN108331570A CN201810209899.6A CN201810209899A CN108331570A CN 108331570 A CN108331570 A CN 108331570A CN 201810209899 A CN201810209899 A CN 201810209899A CN 108331570 A CN108331570 A CN 108331570A
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axis
energy gathering
gathering cap
busbar
coordinate system
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周海
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Chongqing Nishang Technology Co Ltd
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Chongqing Nishang Technology Co Ltd
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Priority to CN201910190436.4A priority patent/CN109798098A/en
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    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/25Methods for stimulating production
    • E21B43/26Methods for stimulating production by forming crevices or fractures
    • E21B43/263Methods for stimulating production by forming crevices or fractures using explosives

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  • Engineering & Computer Science (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)
  • Optical Elements Other Than Lenses (AREA)

Abstract

A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio, including priming device and air transporting arrangement, priming device includes double combination energy-gathering devices, detonation chain and initiator, double combination energy-gathering devices include by left energy gathering cap that explosive charge energy centralization projects to the right, the right energy gathering cap for projecting explosive charge energy centralization to the left, and left energy gathering cap and right energy gathering cap are the paraboloid of revolution of outward opening.Compared with prior art, due to the cumulative action of left energy gathering cap and right energy gathering cap, squeeze the shale in explosive fracturing area simultaneously from left and right two spaces direction respectively, crackle is formed through rapidly the shale zone of fracture of " people " word shape, the specific surface area for increasing shale, to effectively increase the parsing rate and its recovery ratio of shale gas.The cumulative action of the boss outwardly convex of spherical cap shape, further enhances Mohaupt effect.

Description

A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio
Technical field
The present invention relates to the device for increasing shale gas recovery ratio, more particularly to the double combination cumulative pressure breaks of a kind of paraboloid of revolution Increase the device of shale gas recovery ratio.
Background technology
Shale gas is a kind of emerging clear energy sources, because its large storage capacity, exploitation receive much attention due to long the features such as in period.However As gas storage carrier shale body because its Natural porosity it is small, permeability is low, and 95% shale gas well is needed through artificial fracturing Mode increase shale body permeability, can have commercial mining value.
Currently, the method for artificial fracturing includes mainly two classes:When hydraulic fracturing method, second is that foam fracturing method.Water It forces cracking method and mainly achievees the purpose that fracturing rock stratum by injecting highly pressurised liquid into drilling.According to specific fracturing technology, Hydraulic fracturing method includes three kinds of multistage fracturing, riverfrac treatment, hydraulic jetting fracturing etc..Multistage fracturing is to utilize ball sealer or limit Flow Technique separates the technology that reservoir different layers position carries out staged fracturing.Riverfrac treatment is to utilize the induction production of a large amount of clear water injection stratum The fracturing technique in raw water conservancy diversion crack.Hydraulic jetting fracturing is to carry sand body using high speed and high-pressure fluid to carry out perforation and open to split The fracturing technique of seam.Foam fracturing method mainly reaches the mesh of fracturing rock stratum by injecting the liquid gas mixture of high pressure into drilling 's.According to the difference of gas componant, foam fracturing method can be divided into nitrogen foam pressure break and carbon dioxide foaming pressure break etc. two Kind.There is the shortcomings that being difficult to overcome in the fracturing process of rammell in hydraulic fracturing method and foam fracturing method:First, pressure break A large amount of chemical agents are equipped in liquid, it is big to formation damage;Second is that after the perforation of pressure break later stage major fracture, the leakage of fracturing fluid compared with It is serious;Third, the anti-row of fracturing fluid is slower.Most important, the occurrence form of shale gas is based on adsorbed gas, only by broken Broken method increases the specific surface area of shale body, could increase the parsing amount of adsorbed gas, and above-mentioned two classes fracturing process is main Achieve the purpose that volume increase by penetrating through the natural fissure in rock mass, the preservation characteristic of this and shale gas itself is inconsistent.
Chinese patent CN102168543B discloses a kind of method and dress increasing shale gas recovery ratio by explosive manner It sets, described device setting includes loading priming device and air transporting arrangement, wherein loading detonation dress in shale gas well bore hole It sets for surrounding shale to burst apart, air transporting arrangement will be transported to ground by the shale gas oozed out in the shale that is burst apart Face;This method and device have that explosive charge power dissipation, explosive charge capacity usage ratio are low.
Invention content
The technical problem to be solved by the present invention is to overcome the defect of the prior art, the one kind for overcoming above-mentioned technical problem is provided The double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio.
In order to solve the above-mentioned technical problem, a kind of double combination cumulative pressure breaks of paraboloid of revolution of the present invention increase shale gas The technical solution of the device of recovery ratio is as follows:
A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio, and described device is arranged in shale In gas well bore hole, described device includes priming device and air transporting arrangement, and priming device is used to burst apart in surrounding shale, Air transporting arrangement will be transported to ground by the shale gas oozed out in the shale that is burst apart, and the priming device includes detonation chain And initiator, the air transporting arrangement include right flange, isolating device, Oil/Gas Pipe, poroid air inlet pipe;The poroid air inlet pipe It is arranged between the isolating device and the right flange, one end of poroid air inlet pipe is arranged in the through-hole of the right flange, The other end is arranged in the through-hole in isolating device;Poroid air inlet pipe is the pipe with several air admission holes, and one end of Oil/Gas Pipe is set It sets in the through-hole of isolating device, the other end is connected with ground gas collecting apparatus;The priming device further includes double combination cumulative dresses It sets, double combination energy-gathering devices include the left energy gathering cap for projecting explosive charge energy centralization to the right, by explosive charge energy Converge the right energy gathering cap projected to the left, the left flange being arranged on the left of left energy gathering cap, setting left energy gathering cap and right energy gathering cap it Between right flange and casing;
The left energy gathering cap includes left concave outer surface and left concave inside surface, and the left concave outer surface and the left side are recessed Shape inner surface is the paraboloid of revolution of outward opening, and the paraboloid of revolution of the left concave inside surface forms cavity;The left side Energy gathering cap forms an enclosure space with left flange and right flange, and explosive is arranged in the space;The left energy gathering cap Maximum outside diameter is Da, the length of the left energy gathering cap is La
The right energy gathering cap includes right concave outer surface and right concave inside surface, and the right concave outer surface and the right side are recessed Shape inner surface is the paraboloid of revolution of outward opening, and the paraboloid of revolution of the right concave inside surface forms cavity;The right side Energy gathering cap forms an enclosure space with right flange and right flange, and explosive is arranged in the space;The right energy gathering cap Maximum outside diameter is Db, the length of the right energy gathering cap is Lb
The right flange is provided with collar aperture, be outside described sleeve pipe cylinder and its inside be cylindrical hole, the set Pipe sequentially passes through the cavity of the left concave inside surface, the collar aperture of right flange, the cavity of right concave inside surface and right flange Through-hole, described sleeve pipe one end is fixed on the right side of left flange, and the described sleeve pipe other end is fixed on the right side of right flange;
Several initiators, detonation is arranged in interval on the right surface of the left flange and the left surface of the right flange Device is connect by the detonation chain being arranged in described sleeve pipe with ground control unit, and is controlled and detonated by ground control unit The detonation of device;
Several initiators, detonation is arranged in interval on the left surface of the right flange and the right surface of the right flange Device is connect by the detonation chain being arranged in described sleeve pipe with ground control unit, and is controlled and detonated by ground control unit The detonation of device;
Left boss is provided on the right side of the left flange, the left boss is the spherical cap shape of outwardly convex, and the left side is convex The height of projection of platform spherical cap shape is Ht, the maximum open part diameter of a circle of the left boss spherical cap shape is Dt
Right boss is provided on the left of the right flange, the right boss is the spherical cap shape of outwardly convex, and the right side is convex The height of projection of platform spherical cap shape is Ht, the maximum open part diameter of a circle of the right boss spherical cap shape is Dt
Middle boss I is provided on the left of the right flange, the middle boss I is the spherical cap shape of outwardly convex, described The height of projection of I spherical cap shape of middle boss is Ht, the maximum open part diameter of a circle of I spherical cap shape of middle boss is Dt
Middle boss II is provided on the right side of the right flange, the middle boss II is the spherical cap shape of outwardly convex, institute The height of projection for stating II spherical cap shape of middle boss is Ht, the maximum open part diameter of a circle of the left, center, right boss spherical cap shape For Dt
The diameter DtFor explosive diameter D, the height HtFor 3mm~8mm.
Preferably, the rotary shaft of the left concave outer surface is XaThe busbar of axis, the left concave outer surface is busbar A, The busbar A is around the XaAxis rotates to form the left concave outer surface, and the busbar A is the parabolic being made of following equation group Line:
The rotary shaft of the left concave inside surface is XaThe busbar of axis, the left concave inside surface is busbar B, the busbar B is around the XaAxis rotates to form the left concave inside surface, and the busbar B is the parabola being made of following equation group:
The rotary shaft of the right concave outer surface is XbThe busbar of axis, the right concave outer surface is busbar C, the busbar C is around the XbAxis rotates to form the right concave outer surface, and the busbar C is the parabola being made of following equation group:
The rotary shaft of the right concave inside surface is XbThe busbar of axis, the right concave inside surface is busbar D, the busbar D is around the XbAxis rotates to form the right concave inside surface, and the busbar D is the parabola being made of following equation group:
In various above:
Oa-XaYaZaThe coordinate origin of coordinate system is on the axis of the left energy gathering cap and in the length of left energy gathering cap Point, XaAxis, YaAxis and ZaAxis constitutes right hand rectangular coordinate system, XaAxis is overlapped with the axis of the left energy gathering cap, XaAxis positive direction from It is directed toward the right side of left energy gathering cap in the left side of left energy gathering cap;xa、yaAnd zaRespectively XaAxis, YaAxis and ZaThe coordinate variable of axis;
Oa1-Xa1Ya1Za1The coordinate origin of coordinate system is in Oa-XaYaZaIt is (- b in coordinate system1,c1, 0), Xa1Axis, Ya1Axis and Za1Axis constitutes right hand rectangular coordinate system, Za1Axis and ZaAxis is parallel, Xa1Axis and XaAxle clamp angle is θa;xa1、ya1And za1Respectively Xa1 Axis, Ya1Axis and Za1The coordinate variable of axis;
Oa2-Xa2Ya2Za2The coordinate origin of coordinate system is in Oa-XaYaZaIt is (- b in coordinate system2,c2, 0), Xa2Axis, Ya2Axis and Za2Axis constitutes right hand rectangular coordinate system, Za2Axis and ZaAxis is parallel, Xa1Axis and XaAxle clamp angle is θa;xa2、ya2And za2Respectively Xa2 Axis, Ya2Axis and Za2The coordinate variable of axis;
Ob-XbYbZbThe coordinate origin of coordinate system is on the axis of the right energy gathering cap and in the length of right energy gathering cap Point, XbAxis, YbAxis and ZbAxis constitutes right hand rectangular coordinate system, XbAxis is overlapped with the axis of the right energy gathering cap, XbAxis positive direction from It is directed toward the right side of right energy gathering cap in the left side of right energy gathering cap;xb、ybAnd zbRespectively XbAxis, YbAxis and ZbThe coordinate variable of axis;
Ob1-Xb1Yb1Zb1The coordinate origin of coordinate system is in Ob-XbYbZbIt is (b in coordinate system1,c1, 0), Xb1Axis, Yb1Axis and Zb1 Axis constitutes right hand rectangular coordinate system, Zb1Axis and ZbAxis is parallel, Xb1Axis and XbAxle clamp angle is θb;xb1、yb1And zb1Respectively Xb1Axis, Yb1Axis and Zb1The coordinate variable of axis;
Ob2-Xb2Yb2Zb2The coordinate origin of coordinate system is in Ob-XbYbZbIt is (b in coordinate system2,c2, 0), Xb2Axis, Yb2Axis and Zb2 Axis constitutes right hand rectangular coordinate system, Zb2Axis and ZbAxis is parallel, Xb1Axis and XbAxle clamp angle is θb;xb2、yb2And zb2Respectively Xb2Axis, Yb2Axis and Zb2The coordinate variable of axis;
XaAxis and XbAxis is conllinear;
DaAnd DbIt is equal and be D, LaAnd LbIt is equal and be L, θa=-θ, θb=θ;
D is 100mm~800mm, and L is 200mm~1000mm, and θ is 0 °~60 °;
H is the minimum wall thickness (MINI W.) of left energy gathering cap and right energy gathering cap, and H is 1mm~10mm;
a1、b1、c1、a2、b2、c2For parameter, c1It is 0.2~0.90 times of D, c2It is 0.15~0.85 times and c of D1>c2
It solves following equation group and obtains a1、b1Value and a1>0:
It solves following equation group and obtains a2、b2Value and a2>0:
Preferably, the parameter:D is 200mm~500mm, and L is 300mm~600mm, DcFor 200mm~500mm, LcFor 300mm~600mm;
Preferably, the parameter:θ is 30 °~50 °;
Preferably, the parameter c1It is 0.2~0.6 times of D, c2It is 0.15~0.55 times and c of D1>c2
Preferably, the radial minimum wall thickness (MINI W.) H is 1mm~5mm.
Compared with prior art, advantageous effect of the present invention is:Due to Mohaupt effect, parabolical optical characteristics, pass through Left energy gathering cap and right energy gathering cap project explosive charge energy centralization, and explosive charge capacity usage ratio is high, while improving explosion The quantity of the length and shale crackle of the shale crackle in pressure break area;Especially because the cumulative of left energy gathering cap and right energy gathering cap is made With squeezing the shale in explosive fracturing area simultaneously from left and right two spaces direction respectively, crackle is formed through rapidly " people " word shape The shale zone of fracture, the specific surface area of shale is increased, to effectively increase the parsing rate and its recovery ratio of shale gas.Together When, due to the cumulative action of the outwardly convex of the left boss of spherical cap shape, right boss, middle boss I, middle boss II, further increase Strong Mohaupt effect.
Description of the drawings
Fig. 1 is schematic device;
Fig. 2 is left energy gathering cap structural schematic diagram;
Fig. 3 is right energy gathering cap structural schematic diagram;
In above-mentioned Fig. 1-Fig. 3:1- shale gas well bore holes, 2- Oil/Gas Pipes, the poroid air inlet pipe of 3-, 4- air admission holes, the right spills of 5- Outer surface, the right concave inside surfaces of 6-, the right energy gathering caps of 7-, the left concave outer surfaces of 11-, the left concave inside surfaces of 12-, the left flanges of 13-, The left energy gathering caps of 14-, the right flanges of 16-, 17- casings, the right flanges of 18-, 19- isolating devices, 20- initiators, 21- detonation chains.
Specific implementation mode
Below in conjunction with Figure of description, preferred embodiment of the present invention will be described, it should be understood that described herein Preferred embodiment is only for the purpose of illustrating and explaining the present invention and is not intended to limit the present invention
A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio, and described device is arranged in shale In gas well bore hole 1, described device includes priming device and air transporting arrangement, and priming device is for collapsing surrounding shale It splits, air transporting arrangement will be transported to ground by the shale gas oozed out in the shale that is burst apart, and the priming device includes detonation Circuit 21 and initiator 20, the air transporting arrangement include right flange 18, isolating device 19, Oil/Gas Pipe 2, poroid air inlet pipe 3; The poroid air inlet pipe 3 is arranged between the isolating device 19 and the right flange 18, and one end setting of poroid air inlet pipe 3 exists In the through-hole of the right flange 18, the other end is arranged in the through-hole in isolating device 19;Poroid air inlet pipe 3 be with it is several into One end of the pipe of stomata, Oil/Gas Pipe 2 is arranged in the through-hole of isolating device 19, and the other end is connected with ground gas collecting apparatus;It is described Priming device further includes double combination energy-gathering devices, and double combination energy-gathering devices include projecting explosive charge energy centralization to the right Left energy gathering cap 14, by right energy gathering cap 7 that explosive charge energy centralization projects to the left, that a left side in 14 left side of left energy gathering cap is arranged is convex Edge 13, the right flange 16 being arranged between left energy gathering cap 14 and right energy gathering cap 7 and casing 17;
The left energy gathering cap 14 includes left concave outer surface 11 and left concave inside surface 12,11 He of left concave outer surface The left concave inside surface 12 is the paraboloid of revolution of outward opening, and the paraboloid of revolution of the left concave inside surface 12 is formed Cavity;The left energy gathering cap 14 forms an enclosure space with left flange 13 and right flange 16, and is arranged in the space and fries Medicine;The maximum outside diameter of the left energy gathering cap 14 is Da, the length of the left energy gathering cap 14 is La
The right energy gathering cap 7 includes right concave outer surface 5 and right concave inside surface 6, the right concave outer surface 5 and described Right concave inside surface 6 is the paraboloid of revolution of outward opening, and the paraboloid of revolution of the right concave inside surface 6 forms cavity; The right energy gathering cap 7 forms an enclosure space with right flange 18 and right flange 16, and explosive is arranged in the space;It is described The maximum outside diameter of right energy gathering cap 7 is Db, the length of the right energy gathering cap 7 is Lb
The right flange 16 is provided with collar aperture, 17 outside of described sleeve pipe be cylinder and its inside be cylindrical hole, institute State casing 17 sequentially pass through the cavity of the left concave inside surface 12, the collar aperture of right flange 16, right concave inside surface 6 sky The through-hole of chamber and right flange 18,17 one end of described sleeve pipe are fixed on the right side of left flange 13, and 17 other end of described sleeve pipe is fixed In the right side of right flange 18;
Several initiators are arranged in interval on the right surface of the left flange 13 and the left surface of the right flange 16 20, initiator 20 is connect by the detonation chain 21 being arranged in described sleeve pipe 17 with ground control unit, and is controlled by ground The detonation of device control initiator 20 processed;
Several initiators are arranged in interval on the left surface of the right flange 18 and the right surface of the right flange 16 20, initiator 20 is connect by the detonation chain 21 being arranged in described sleeve pipe 17 with ground control unit, and is controlled by ground The detonation of device control initiator 20 processed;
The right side of the left flange 13 is provided with left boss, and the left boss is the spherical cap shape of outwardly convex, the left side The height of projection of boss spherical cap shape is Ht, the maximum open part diameter of a circle of the left boss spherical cap shape is Dt
The left side of the right flange 18 is provided with right boss, and the right boss is the spherical cap shape of outwardly convex, the right side The height of projection of boss spherical cap shape is Ht, the maximum open part diameter of a circle of the right boss spherical cap shape is Dt
The left side of the right flange 16 is provided with middle boss I, and the middle boss I is the spherical cap shape of outwardly convex, institute The height of projection for stating I spherical cap shape of middle boss is Ht, the maximum open part diameter of a circle of I spherical cap shape of middle boss is Dt
The right side of the right flange 16 is provided with middle boss II, and the middle boss II is the spherical cap shape of outwardly convex, The height of projection of II spherical cap shape of middle boss is Ht, the left, center, right boss spherical cap shape maximum open part circle it is straight Diameter is Dt
The diameter DtFor explosive diameter D, the height HtFor 3mm~8mm.
Establish Oa-XaYaZaCoordinate system, Oa1-Xa1Ya1Za1Coordinate system, Oa2-Xa2Ya2Za2Coordinate system, Ob-XbYbZbCoordinate system, Ob1-Xb1Yb1Zb1Coordinate system, Ob2-Xb2Yb2Zb2Coordinate system and Oc-XcYcZcCoordinate system is as follows:
Oa-XaYaZaThe coordinate origin of coordinate system is on the axis of the left energy gathering cap 14 and in the length of left energy gathering cap 14 Midpoint, XaAxis, YaAxis and ZaAxis constitutes right hand rectangular coordinate system, XaAxis is overlapped with the axis of the left energy gathering cap 14, XaAxis is just The right side of left energy gathering cap 14 is directed toward from the left side of left energy gathering cap 14 in direction;xa、yaAnd zaRespectively XaAxis, YaAxis and ZaThe coordinate of axis Variable;
Oa1-Xa1Ya1Za1The coordinate origin of coordinate system is in Oa-XaYaZaIt is (- b in coordinate system1,c1, 0), Xa1Axis, Ya1Axis and Za1Axis constitutes right hand rectangular coordinate system, Za1Axis and ZaAxis is parallel, Xa1Axis and XaAxle clamp angle is θa;xa1、ya1And za1Respectively Xa1 Axis, Ya1Axis and Za1The coordinate variable of axis;
Oa2-Xa2Ya2Za2The coordinate origin of coordinate system is in Oa-XaYaZaIt is (- b in coordinate system2,c2, 0), Xa2Axis, Ya2Axis and Za2Axis constitutes right hand rectangular coordinate system, Za2Axis and ZaAxis is parallel, Xa1Axis and XaAxle clamp angle is θa;xa2、ya2And za2Respectively Xa2 Axis, Ya2Axis and Za2The coordinate variable of axis;
Ob-XbYbZbThe coordinate origin of coordinate system is on the axis of the right energy gathering cap 7 and in the length of right energy gathering cap 7 Midpoint, XbAxis, YbAxis and ZbAxis constitutes right hand rectangular coordinate system, XbAxis is overlapped with the axis of the right energy gathering cap 7, XbAxis positive direction The right side of right energy gathering cap 7 is directed toward from the left side of right energy gathering cap 7;xb、ybAnd zbRespectively XbAxis, YbAxis and ZbThe coordinate variable of axis;
Ob1-Xb1Yb1Zb1The coordinate origin of coordinate system is in Ob-XbYbZbIt is (b in coordinate system1,c1, 0), Xb1Axis, Yb1Axis and Zb1 Axis constitutes right hand rectangular coordinate system, Zb1Axis and ZbAxis is parallel, Xb1Axis and XbAxle clamp angle is θb;xb1、yb1And zb1Respectively Xb1Axis, Yb1Axis and Zb1The coordinate variable of axis;
Ob2-Xb2Yb2Zb2The coordinate origin of coordinate system is in Ob-XbYbZbIt is (b in coordinate system2,c2, 0), Xb2Axis, Yb2Axis and Zb2 Axis constitutes right hand rectangular coordinate system, Zb2Axis and ZbAxis is parallel, Xb1Axis and XbAxle clamp angle is θb;xb2、yb2And zb2Respectively Xb2Axis, Yb2Axis and Zb2The coordinate variable of axis;
XaAxis and XbAxis is conllinear.
The rotary shaft of the left concave outer surface 11 is XaThe busbar of axis, the left concave outer surface 11 is busbar A, described Busbar A is around the XaAxis rotates to form the left concave outer surface 11, and the busbar A is the parabolic being made of following equation group Line:
The rotary shaft of the left concave inside surface 12 is XaThe busbar of axis, the left concave inside surface 12 is busbar B, described Busbar B is around the XaAxis rotates to form the left concave inside surface 12, and the busbar B is the parabolic being made of following equation group Line:
The rotary shaft of the right concave outer surface 5 is XbThe busbar of axis, the right concave outer surface 5 is busbar C, the mother Line C is around the XbAxis rotates to form the right concave outer surface 5, and the busbar C is the parabola being made of following equation group:
The rotary shaft of the right concave inside surface 6 is XbThe busbar of axis, the right concave inside surface 6 is busbar D, the mother Line D is around the XbAxis rotates to form the right concave inside surface 6, and the busbar D is the parabola being made of following equation group:
In various above:
DaAnd DbIt is equal and be D, LaAnd LbIt is equal and be L, θa=-θ, θb=θ;
D is 100mm~800mm, and L is 200mm~1000mm, and θ is 0 °~60 °;
H is the minimum wall thickness (MINI W.) of left energy gathering cap 14 and right energy gathering cap 7, and H is 1mm~10mm;
a1、b1、c1、a2、b2、c2For parameter, c1It is 0.2~0.90 times of D, c2It is 0.15~0.85 times and c of D1>c2
The major parameter of right energy gathering cap 7 is defined below.
The parabola mistake of the right concave outer surface 5 of right energy gathering cap 7With2 points, i.e.,:WhenWhen,WhenWhen,It brings into after set of equations (13) arranges and obtains:
It solves above equation group (17) and obtains a1、b1Value and a1>0, to ensure parabola outward opening, therefore it is required that a1> 0;
The minimum wall thickness (MINI W.) of right energy gathering cap 7 is H, then the 6 parabola mistake of right concave inside surface of right energy gathering cap 7 With2 points, i.e.,:WhenWhen,WhenWhen,It brings into Set of equations (14) obtains after arranging:
It solves above equation group (18) and obtains a2、b2Value and a2>0, to ensure parabola outward opening, therefore it is required that a2> 0;
In the present embodiment, θ=45 ° are chosen, then are had:θa=-45 °, θb=45 °;Due to sin45 °=cos45 °, then equation Group (17) is transformed to equation group (19):
In equation group (19), P1、Q1Calculation formula is:
P1=D-L-2c1; (20)
Q1=D+L-2c1; (21)
Equation group (19) is solved, b is cast out1<0 solution can be obtained with ensureing parabola outward opening:
Similarly, θ=45 ° are chosen, then are had:θa=-45 °, θb=45 °;Due to sin45 °=cos45 °, then equation group (18) It is transformed to equation group (23):
In equation group (23), P2、Q2Calculation formula is:
P2=D-L-2c2-2H; (24)
Q2=D+L-2c2-2H; (25)
Equation group (23) is solved, b is cast out2<0 solution can be obtained with ensureing parabola outward opening:
In the present embodiment, each parameter or coefficient are specifically chosen and are solved as follows:
It chooses:D=300mm, L=400mm, La=400mm, Lb=400mm, takes c1For the 0.2 times i.e. c of D1=60mm, takes c2For the 0.15 times i.e. c of D2=45mm, H=2mm is calculated according to (22) and (26):
b1=179.0724809mm, a1=0.007938555mm;
b2=184.116701mm, a2=0.008717154mm.
The major parameter of right energy gathering cap 7 determined above.Left energy gathering cap 14 is left-right symmetric relation with right energy gathering cap 7, because This, the major parameter of left energy gathering cap 14 also determines therewith.
The technical solution of the present embodiment and its major parameter determination finish as a result,.
It is preferable that above example integrates Mohaupt effect.
According to Mohaupt effect, after explosive charge, explosion product is at high temperature under high pressure substantially along explosive normal to a surface side To what is dispersed outward, therefore, explosive with groove will appear one is converged, speed and pressure after ignition in recess axis Strong all very high explosion product stream, in a certain range puts together the explosion energy that explosive charge releases.This hair The outer surface of bright left energy gathering cap 14 and right energy gathering cap 7 and inner surface are the paraboloid of revolution, busbar A, busbar B, busbar C, mother Line D is parabola, and the rotary shaft of the paraboloid of revolution has angle with the parabolical axis of symmetry;The parabola of left energy gathering cap 14 The axis of symmetry around the paraboloid of revolution rotary shaft rotation after form left circular conical surface, the parabolical axis of symmetry of right energy gathering cap 7 Right circular conical surface is formed after the rotary shaft rotation of the paraboloid of revolution;Due to parabolical light characteristic, i.e., the light warp through focus For light ray parallel after parabolic reflective in the parabolical axis of symmetry, this parabolical characteristic further enhances cumulative effect It answers;After explosive charge, the explosion energy of left energy gathering cap 14 is converged to space dextrad along left circular conical surface and is projected, right energy gathering cap 7 it is quick-fried Fried energy, which is converged along right circular conical surface to space left-hand, to be projected, and two spaces direction squeezes the shale in explosive fracturing area, crackle simultaneously It is formed through the shale zone of fracture of " people " word shape rapidly, increases the specific surface area of shale, to effectively increase shale gas Parsing rate and its recovery ratio.Simultaneously as the left boss of spherical cap shape, right boss, middle boss I, middle boss II is outside The cumulative action of protrusion, further enhances Mohaupt effect.
To ensure that the wall thickness of left energy gathering cap 14 and the wall thickness of right energy gathering cap 7 are gradually reduced from centre to both sides, it is desirable that c1> c2;Similarly, the wall thickness for energy gathering cap in guarantee is gradually reduced from centre to both sides, it is desirable that a3>a4
Parameter c1、c2Value, should be selected according to performances such as the hardness of shale, parameter c1、c2Value it is smaller, explosion energy converge Poly- more to concentrate, explosive fracturing area is deep and narrow, the length of shale crackle is longer;Conversely, explosion energy convergence more dissipates, explosive fracturing Area is wide and shallow, the length of shale crackle is shorter.c1It is 0.2~0.90 times of D, c2It is 0.15~0.85 times and c of D1>c2;It is preferred that Ground:c1It is 0.2~0.6 times of D, c2It is 0.15~0.55 times and c of D1>c2
The value of the performances selection parameter such as hardness according to shale θ, θ values are bigger, and explosive fracturing area is narrower, the easier pressure of shale Broken, shale crackle length is shorter and the quantity of shale crackle is more;θ values are smaller, and explosive fracturing area is wider, shale is more not easy to press Broken, shale crackle length is longer and the quantity of shale crackle is fewer;θ values are 0 °~60 °, preferably:θ values be 30 °~ 50°。
Left energy gathering cap 14 and right energy gathering cap 7 are made by the aluminium alloy of 7A09 models, and cost performance is best.
Left flange 13, right flange 16 and right flange 18 are made by 4350 steel alloys, and cost performance is best.
Described sleeve pipe 17 is made by HP9-4-20 type high temperature resistant stainless steel pipes, and cost performance is best.
A kind of double combination cumulative pressure breaks of paraboloid of revolution disclosed in this invention increase the device of shale gas recovery ratio, are making When making, explosive is put into priming device in advance, then whole device is arranged in shale gas well bore hole 1 again;Initiator 20 include electric cap, digital primer etc., and detonation mode includes electric initiating, digital detonation etc.;The explosive includes liquid explosives, consolidates Body explosive etc..
Above example is the primary structure of the present invention, form parameter, remaining CONSTRUCTED SPECIFICATION is common according to this professional domain Common technical knowledge and conventional techniques are designed and select.

Claims (8)

1. a kind of double combination cumulative pressure breaks of paraboloid of revolution increase the device of shale gas recovery ratio, described device is arranged in shale gas In well bore hole, described device includes priming device and air transporting arrangement, and priming device is for bursting apart surrounding shale, gas Body conveying device will be transported to ground by the shale gas oozed out in the shale that is burst apart, the priming device include detonation chain and Initiator, the air transporting arrangement include right flange, isolating device, Oil/Gas Pipe, poroid air inlet pipe;The poroid air inlet pipe is set It sets between the isolating device and the right flange, one end of poroid air inlet pipe is arranged in the through-hole of the right flange, separately One end is arranged in the through-hole in isolating device;Poroid air inlet pipe is the pipe with several air admission holes, and one end of Oil/Gas Pipe is arranged In the through-hole of isolating device, the other end is connected with ground gas collecting apparatus;It is characterized in that the priming device further includes double groups Close energy-gathering device, double combination energy-gathering devices include the left energy gathering cap for projecting explosive charge energy centralization to the right, by explosive Explosion energy converges the right energy gathering cap projected to the left, the left flange being arranged on the left of left energy gathering cap, is arranged on left energy gathering cap and the right side Right flange between energy gathering cap and casing;
The left energy gathering cap includes left concave outer surface and left concave inside surface, in the left concave outer surface and the left spill Surface is the paraboloid of revolution of outward opening, and the paraboloid of revolution of the left concave inside surface forms cavity;The left cumulative Cover forms an enclosure space with left flange and right flange, and explosive is arranged in the space;The maximum of the left energy gathering cap Outer diameter is Da, the length of the left energy gathering cap is La
The right energy gathering cap includes right concave outer surface and right concave inside surface, in the right concave outer surface and the right spill Surface is the paraboloid of revolution of outward opening, and the paraboloid of revolution of the right concave inside surface forms cavity;The right cumulative Cover forms an enclosure space with right flange and right flange, and explosive is arranged in the space;The maximum of the right energy gathering cap Outer diameter is Db, the length of the right energy gathering cap is Lb
The right flange is provided with collar aperture, be outside described sleeve pipe cylinder and its inside be cylindrical hole, described sleeve pipe according to Secondary leading to across the cavity of the left concave inside surface, the collar aperture of right flange, the cavity of right concave inside surface and right flange Hole, described sleeve pipe one end are fixed on the right side of left flange, and the described sleeve pipe other end is fixed on the right side of right flange;
Left boss is provided on the right side of the left flange, the left boss is the spherical cap shape of outwardly convex, the left boss ball The height of projection of crown shape is Ht, the maximum open part diameter of a circle of the left boss spherical cap shape is Dt
Right boss is provided on the left of the right flange, the right boss is the spherical cap shape of outwardly convex, the right boss ball The height of projection of crown shape is Ht, the maximum open part diameter of a circle of the right boss spherical cap shape is Dt
Middle boss I is provided on the left of the right flange, the middle boss I is the spherical cap shape of outwardly convex, the convexity The height of projection of I spherical cap shape of platform is Ht, the maximum open part diameter of a circle of I spherical cap shape of middle boss is Dt
Middle boss II is provided on the right side of the right flange, the middle boss II is the spherical cap shape of outwardly convex, in described The height of projection of II spherical cap shape of boss is Ht, the maximum open part diameter of a circle of the left, center, right boss spherical cap shape is Dt
The diameter DtFor explosive diameter D, the height HtFor 3mm~8mm.
2. a kind of double combination cumulative pressure breaks of paraboloid of revolution according to claim 1 increase the device of shale gas recovery ratio, It is characterized in that,
The rotary shaft of the left concave outer surface is XaThe busbar of axis, the left concave outer surface is busbar A, and the busbar A is around institute State XaAxis rotates to form the left concave outer surface, and the busbar A is the parabola being made of following equation group:
The rotary shaft of the left concave inside surface is XaThe busbar of axis, the left concave inside surface is busbar B, and the busbar B is around institute State XaAxis rotates to form the left concave inside surface, and the busbar B is the parabola being made of following equation group:
The rotary shaft of the right concave outer surface is XbThe busbar of axis, the right concave outer surface is busbar C, and the busbar C is around institute State XbAxis rotates to form the right concave outer surface, and the busbar C is the parabola being made of following equation group:
The rotary shaft of the right concave inside surface is XbThe busbar of axis, the right concave inside surface is busbar D, and the busbar D is around institute State XbAxis rotates to form the right concave inside surface, and the busbar D is the parabola being made of following equation group:
In various above:
Oa-XaYaZaThe midpoint of length of the coordinate origin of coordinate system on the axis of the left energy gathering cap and in left energy gathering cap, Xa Axis, YaAxis and ZaAxis constitutes right hand rectangular coordinate system, XaAxis is overlapped with the axis of the left energy gathering cap, XaAxis positive direction is poly- from a left side It is directed toward the right side of left energy gathering cap in the left side that can be covered;xa、yaAnd zaRespectively XaAxis, YaAxis and ZaThe coordinate variable of axis;
Oa1-Xa1Ya1Za1The coordinate origin of coordinate system is in Oa-XaYaZaIt is (- b in coordinate system1,c1, 0), Xa1Axis, Ya1Axis and Za1Axis Constitute right hand rectangular coordinate system, Za1Axis and ZaAxis is parallel, Xa1Axis and XaAxle clamp angle is θa;xa1、ya1And za1Respectively Xa1Axis, Ya1 Axis and Za1The coordinate variable of axis;
Oa2-Xa2Ya2Za2The coordinate origin of coordinate system is in Oa-XaYaZaIt is (- b in coordinate system2,c2, 0), Xa2Axis, Ya2Axis and Za2Axis Constitute right hand rectangular coordinate system, Za2Axis and ZaAxis is parallel, Xa1Axis and XaAxle clamp angle is θa;xa2、ya2And za2Respectively Xa2Axis, Ya2 Axis and Za2The coordinate variable of axis;
Ob-XbYbZbThe midpoint of length of the coordinate origin of coordinate system on the axis of the right energy gathering cap and in right energy gathering cap, Xb Axis, YbAxis and ZbAxis constitutes right hand rectangular coordinate system, XbAxis is overlapped with the axis of the right energy gathering cap, XbAxis positive direction is poly- from the right side It is directed toward the right side of right energy gathering cap in the left side that can be covered;xb、ybAnd zbRespectively XbAxis, YbAxis and ZbThe coordinate variable of axis;
Ob1-Xb1Yb1Zb1The coordinate origin of coordinate system is in Ob-XbYbZbIt is (b in coordinate system1,c1, 0), Xb1Axis, Yb1Axis and Zb1Axis structure At right hand rectangular coordinate system, Zb1Axis and ZbAxis is parallel, Xb1Axis and XbAxle clamp angle is θb;xb1、yb1And zb1Respectively Xb1Axis, Yb1Axis And Zb1The coordinate variable of axis;
Ob2-Xb2Yb2Zb2The coordinate origin of coordinate system is in Ob-XbYbZbIt is (b in coordinate system2,c2, 0), Xb2Axis, Yb2Axis and Zb2Axis structure At right hand rectangular coordinate system, Zb2Axis and ZbAxis is parallel, Xb1Axis and XbAxle clamp angle is θb;xb2、yb2And zb2Respectively Xb2Axis, Yb2Axis And Zb2The coordinate variable of axis;
XaAxis and XbAxis is conllinear;
DaAnd DbIt is equal and be D, LaAnd LbIt is equal and be L, θa=-θ, θb=θ;
D is 100mm~800mm, and L is 200mm~1000mm, and θ is 0 °~60 °;
H is the minimum wall thickness (MINI W.) of left energy gathering cap and right energy gathering cap, and H is 1mm~10mm;
a1、b1、c1、a2、b2、c2For parameter, c1It is 0.2~0.90 times of D, c2It is 0.15~0.85 times and c of D1>c2
It solves following equation group and obtains a1、b1Value and a1>0:
It solves following equation group and obtains a2、b2Value and a2>0:
3. a kind of double combination cumulative pressure breaks of paraboloid of revolution according to claim 2 increase the device of shale gas recovery ratio, It is characterized in that, the parameter θ is 30 °~50 °.
4. a kind of double combination cumulative pressure breaks of paraboloid of revolution according to claim 2 increase the device of shale gas recovery ratio, It is characterized in that, the parameter θ is 45 °, parameter a1、b1、a2、b2Pass sequentially through following formula calculating:
P1=D-L-2c1
Q1=D+L-2c1
P2=D-L-2c2-2H;
Q2=D+L-2c2-2H;
5. a kind of double combination cumulative pressure breaks of paraboloid of revolution according to claim 2 increase the device of shale gas recovery ratio, It is characterized in that, the parameter c1It is 0.2~0.6 times of D, c2It is 0.15~0.55 times and c of D1>c2
6. a kind of double combination cumulative pressure breaks of paraboloid of revolution according to claim 2 increase the device of shale gas recovery ratio, It is characterized in that, the parameter D is 200mm~500mm, L is 300mm~600mm.
7. a kind of double combination cumulative pressure breaks of paraboloid of revolution according to claim 2 increase the device of shale gas recovery ratio, It is characterized in that, the radial direction minimum wall thickness (MINI W.) H is 1mm~5mm.
8. the double combination cumulative pressure breaks of a kind of paraboloid of revolution according to claim 2,4,5,6 or 7 increase shale gas harvesting The device of rate, which is characterized in that the parameter D=300mm, L=400mm, La=400mm, Lb=400mm, c1=60mm, c2 =45mm, H=2mm, b1=179.0724809mm, a1=0.007938555mm, b2=184.116701mm, a2= 0.008717154mm。
CN201810209899.6A 2018-03-14 2018-03-14 A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio Withdrawn CN108331570A (en)

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CN108547605A (en) * 2018-03-14 2018-09-18 重庆霓裳科技有限公司 A kind of surface of revolution three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108487895A (en) * 2018-03-14 2018-09-04 重庆楚骓科技有限责任公司 A kind of circular arc cylinder three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108487889A (en) * 2018-03-14 2018-09-04 重庆能源职业学院 A kind of paraboloid of revolution three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108590618A (en) * 2018-03-14 2018-09-28 重庆霓裳科技有限公司 A kind of cylinder three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108590619A (en) * 2018-03-14 2018-09-28 重庆霓裳科技有限公司 A kind of circular arc cylinder three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108487891A (en) * 2018-03-14 2018-09-04 重庆楚骓科技有限责任公司 A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio
CN108412476A (en) * 2018-03-14 2018-08-17 重庆楚骓科技有限责任公司 A kind of paraboloid of revolution three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108487890A (en) * 2018-03-14 2018-09-04 重庆能源职业学院 A kind of parabolic cylinder three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108331570A (en) * 2018-03-14 2018-07-27 重庆霓裳科技有限公司 A kind of double combination cumulative pressure breaks of the paraboloid of revolution increase the device of shale gas recovery ratio
CN108361012B (en) * 2018-03-14 2020-09-08 重庆能源职业学院 Device for increasing shale gas recovery ratio by three-combination energy-gathering fracturing of arc surface
CN108487894A (en) * 2018-03-14 2018-09-04 重庆楚骓科技有限责任公司 A kind of surface of revolution three combines the device of cumulative pressure break increase shale gas recovery ratio
CN108331567B (en) * 2018-03-14 2020-09-11 诸暨市源浦机械科技有限公司 Device for increasing shale gas recovery ratio by parabolic cylinder three-combination energy-gathering fracturing

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