CN112709559A - Hydraulic pressure-multiplying injector - Google Patents

Hydraulic pressure-multiplying injector Download PDF

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Publication number
CN112709559A
CN112709559A CN201911058736.3A CN201911058736A CN112709559A CN 112709559 A CN112709559 A CN 112709559A CN 201911058736 A CN201911058736 A CN 201911058736A CN 112709559 A CN112709559 A CN 112709559A
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CN
China
Prior art keywords
piston
cylinder
oil
hydraulic pressure
pressure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201911058736.3A
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Chinese (zh)
Inventor
张晓义
杨波
汪凤威
白文海
徐青竹
丁一铭
张骥潇
王宁辉
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panjin Lianxin Industrial Co ltd
Original Assignee
Panjin Lianxin Industrial Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Panjin Lianxin Industrial Co ltd filed Critical Panjin Lianxin Industrial Co ltd
Priority to CN201911058736.3A priority Critical patent/CN112709559A/en
Publication of CN112709559A publication Critical patent/CN112709559A/en
Pending legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/25—Methods for stimulating production
    • E21B43/26—Methods for stimulating production by forming crevices or fractures
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B3/00—Machines or pumps with pistons coacting within one cylinder, e.g. multi-stage
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
    • F04B53/10—Valves; Arrangement of valves
    • F04B53/1002—Ball valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
    • F04B53/14—Pistons, piston-rods or piston-rod connections
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B9/00—Piston machines or pumps characterised by the driving or driven means to or from their working members
    • F04B9/08—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid
    • F04B9/10—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid

Abstract

The invention relates to a device for removing blockage of a liquid pressure oil layer in oil extraction operation of an oil well, in particular to a device for removing blockage of a liquid pressure oil layer, which comprises the following steps: a hydraulic pressure doubling injector; the hydraulic pressure-multiplying injector comprises a cylinder barrel system, a piston string system and a valve structure; the cylinder system is internally provided with a piston string system, and the valve structure is arranged at the other end of the cylinder system; the hydraulic pressure-multiplying injector is used in an oil well, and the upper end of the hydraulic pressure-multiplying injector is connected with an oil pipe; the piston string system can reciprocate in the cylinder system, and the moving stroke is the length of the cylinder minus the length of the piston; when hydraulic pressure returns: on one hand, the piston is driven to move upwards from the oil well ring sleeve space, and the liquid quantity is stored; when hydraulic pressure is positive: from the oil pipe, the piston is made to move downwards, high pressure (double pressure) is formed under the end piston, and the high pressure is pushed out; after the forward direction and the backward direction are alternately reversed, the liquid in the ring sleeve is continuously squeezed into the oil layer of the oil well.

Description

Hydraulic pressure-multiplying injector
The technical field is as follows:
the invention relates to a device for removing blockage of a liquid pressure oil layer in oil extraction operation of an oil well, in particular to a device for removing blockage of a liquid pressure oil layer, which comprises the following steps: a hydraulic pressure doubling injector.
Technical Field
At present, in the process of oil field development, for the oil increasing and injection increasing of some low-porosity and low-permeability oil layers, a hydraulic fracturing or near-wellbore area chemical blocking removal method is mainly adopted, and due to the fact that the hydraulic fracturing cost is high, the number of oil wells adopting measures is small, the chemical blocking removal cannot change the structure of the oil layer, and the effect is not obvious. At present, although the methods for solving the problem of oil reservoir blockage are many, for example: high-energy gas fracturing, hydraulic pulse blockage removal, ultrasonic blockage removal and the like, but the effects are not obvious enough.
Disclosure of Invention
The invention aims to provide a method for preparing the following components: the hydraulic pressure-multiplying injector utilizes a hydraulic pump to inject conventional high-pressure liquid into the hydraulic pressure-multiplying injector in the process of oil layer blockage removal, and then the conventional high-pressure liquid is converted into liquid output with ultrahigh pressure more than 3 times and is directly extruded into an oil layer, so that the compact oil layer in a near well zone is forced to be pressed open and crushed, a plurality of cracks are extruded open, the original stratum structure is changed, the flow conductivity of the oil layer is improved like a small-sized fracturing effect, and the yield of an oil well or the injection amount of a water well is improved. The novel method for unblocking the pressure-multiplied injection oil layer is low in cost, quick in effect, simple in field construction, safe and practical, and solves the problem of oil-increasing and injection-increasing of the low-pore and low-permeability oil layer.
In order to achieve the purpose, the hydraulic pressure doubling injector is an important component for injecting liquid pressure doubling into an oil layer for deblocking work. The hydraulic pressure-multiplying injector is a multistage hydraulic injection device with special structure formed by orderly connecting a plurality of hydraulic cylinders and two sets of check valves for liquid inlet and outlet in series.
The hydraulic pressure-multiplying injector comprises a cylinder barrel system, a piston string system and a valve structure; the piston string system is arranged in the cylinder barrel system, and the valve structure is arranged at the other end of the cylinder barrel system.
The cylinder barrel system is a cylinder barrel group formed by serially connecting hydraulic cylinders, the cylinder barrel group comprises N cylinder barrels, an upper cylinder barrel coupling, an operation short joint, an upper coupling, a cylinder barrel coupling, a lower cylinder barrel coupling and a tail end cylinder barrel, two ends of the cylinder barrel group are respectively fixed by the upper coupling and the lower coupling, and the upper coupling is connected with a head end cylinder barrel through the operation short joint; the N cylinder barrels are fixedly connected through a cylinder barrel coupling, two ends of the inside of the cylinder barrel coupling are respectively provided with an oil seal and an oil seal pressing cap, and the oil seal is used for ensuring that the piston rod and the cylinder barrel coupling are sealed; the lower part of the tail end cylinder barrel is provided with a central hole; two piston rod guide rings are arranged in the central hole, and the guide rings are used for righting the piston rod and preventing the piston rod from being damaged due to friction between the piston rod and the inner hole of the cylinder coupling.
The piston string system comprises N pistons, a piston oil seal, a piston rod, a piston guide ring, a head end piston and a piston oil seal pressing cap, wherein N is less than N by one piston rod; two ends of each of the N pistons are respectively provided with a piston oil seal and a piston oil seal pressing cap, and the piston oil seals are used for ensuring the sealing between the pistons and the cylinder barrels; except the first-end piston, the other pistons are provided with holes in the axial direction, so that the piston string is communicated with the inner holes to form a whole and moves together when working; the piston rod is provided with through holes in the axial direction, and the lower end of the piston rod is provided with through holes vertical to the axis, so that a hydraulic passage is formed; and the outer sides of the N pistons are provided with piston guide rings for righting the pistons and avoiding direct contact friction between the pistons and the cylinder barrel.
The piston string is arranged in the cylinder barrel system, when the piston string is subjected to external liquid pressure from the upper coupling, liquid is filled into an annular space defined by the outside of each piston rod and the cylinder barrel through the inner hole and the side hole of the piston rod connected in series, the N pistons are all subjected to a common pressure acting force to push the piston string to move, and the pressure force on the piston string is
FString＝Q(SPiston N1+SPiston N2+SPiston N3+SPiston N4)
The output of the piston string is piston N4, and the pressure output by piston N4 is:
Qpiston N4＝FString/SPiston N4
The pressure output by the piston is more than 3 times greater than the pressure input by the system; after the liquid with the ultrahigh pressure of more than 3 times is output, the liquid is directly extruded into an oil layer, the compact oil layer in a near well zone is forced to be pressed open and crushed, a plurality of cracks are extruded open, the original stratum structure is changed, the liquid is like a small fracturing effect, the flow conductivity of the oil layer is improved, and the yield of an oil well or the injection amount of a water well is improved.
The valve structure is assembled in the lower coupling of the cylinder barrel and comprises a crossed core body and two valve balls.
The crossed core body is welded in the lower coupling of the cylinder barrel; the side face of the crossed core body is provided with a hole corresponding to the side face hole of the lower coupling of the cylinder barrel, and two channels of liquid inlet and liquid outlet which are mutually crossed but not communicated are formed.
The two valve balls are respectively arranged at the two ends of the crossed core body through the ball drags and the valve seats.
The valve ball at the front end of the crossed core body passes through the liquid inlet valve cover, and the liquid inlet valve is formed by the oil inlet cover plug and the spring; the valve ball at the tail end of the crossed core body forms an oil outlet valve through an oil outlet valve plug, an oil outlet valve cover and a spring.
When the valve structure is in a liquid inlet working state: the liquid with pressure outside passes through the side hole of the lower coupling of the cylinder barrel from the outside, the valve ball and the ball puller are pushed up through the side hole and the central hole of the crossed core body and the valve seat, the spring is compressed, and the liquid enters the upper space of the liquid outlet valve through the side hole of the liquid inlet valve cover; at this time, the outlet valve is closed.
The valve structure is in a liquid outlet working state: when the liquid pressure stored in the upper space of the liquid outlet valve is greater than the liquid pressure in the lower space of the liquid outlet valve, the liquid pressure pushes the valve ball and the ball drags of the liquid outlet valve, the spring is compressed, and the liquid enters the lower space of the liquid outlet valve through the side hole of the oil outlet valve cover; at this point the inlet valve is closed.
The hydraulic pressure-multiplying injector is used in an oil well, and the upper end of the hydraulic pressure-multiplying injector is connected with an oil pipe; the piston string system can reciprocate in the cylinder system, and the travel of the movement is the length of the cylinder minus the length of the piston. When hydraulic pressure returns: on one hand, the piston is driven to move upwards from the oil well ring sleeve space, and the liquid quantity is stored; when hydraulic pressure is positive: from the oil pipe, the piston is made to move downwards, high pressure (double pressure) is formed under the end piston, and the high pressure is pushed out; after the forward direction and the backward direction are alternately reversed, the liquid in the ring sleeve is continuously squeezed into the oil layer of the oil well.
Drawings
Fig. 1 is a schematic diagram of a hydraulic pressure doubling injector.
Fig. 2 is a schematic diagram of the cylinder system of the hydraulic pressure doubling injector.
Fig. 3 is a schematic diagram of a piston string system of a hydraulic pressure doubling injector.
Fig. 4 is a schematic diagram of a valve structure of a hydraulic pressure doubling injector.
Shown in the figure: the oil-gas cylinder comprises a cylinder barrel 1, a cylinder barrel upper coupling 2, an operation nipple 3, an upper coupling 4, a cylinder barrel coupling 5, an oil seal 6, an oil seal pressing cap 7, a cylinder barrel lower coupling 8, a cross core body 9, an oil outlet cover 10, a ball puller 11, a spring 12, an oil outlet cover plug 13, a lower coupling 14, a liquid inlet valve cover 15, a valve seat 16, a valve ball 17, an oil inlet cover plug 18, a lower cylinder barrel 19, a piston rod guide ring 20, a piston rod 21, a piston 22, a piston oil seal 23, a piston oil seal pressing cap 24 and a first piston 25.
The invention is further described below with reference to the accompanying drawings:
fig. 1 is a schematic diagram of a hydraulic pressure doubling injector.
The hydraulic pressure-multiplying injector shown in fig. 1 is a hydraulic injection device with a multistage special structure formed by orderly connecting a plurality of hydraulic cylinders and two sets of check valves for liquid inlet and outlet in series. The hydraulic pressure-multiplying injector comprises a cylinder barrel system, a piston string system and a valve structure; the piston string system is arranged in the cylinder barrel system, and the valve structure is arranged at the other end of the cylinder barrel system.
Fig. 2 is a schematic diagram of the cylinder system of the hydraulic pressure doubling injector.
As shown in fig. 2, a piston rod oil seal and an oil seal pressing cap are arranged at two ends inside each cylinder coupling, and the piston rod oil seal is used for ensuring that the piston rod and the cylinder coupling are sealed; two piston rod guide rings are arranged in the central hole, and the guide rings are used for righting the piston rod and preventing the piston rod from being damaged due to friction between the piston rod and the inner hole of the cylinder coupling.
Fig. 3 is a schematic diagram of a piston string system of a hydraulic pressure doubling injector.
As shown in fig. 3, the piston string structure is composed of three piston rods and four pistons, two ends of each piston are respectively provided with an oil seal and an oil seal pressing cap, and the piston oil seal is used for ensuring the sealing between the piston and the cylinder barrel; the axial directions of the piston A, the piston B and the piston C are all provided with holes, and the piston D is not provided with a hole; each piston rod is provided with a through hole in the axial direction, and the lower end of each piston rod is provided with a through hole vertical to the axial center, so that a hydraulic passage is formed;
the outer side of each piston is provided with a piston guide ring which is used for righting the piston and avoiding the direct contact friction between the piston and the cylinder barrel;
the inner holes of the piston string are communicated to form a whole, and the piston string move together when working; in the stress analysis of the piston string shown in fig. 3 in the cylinder system structure shown in fig. 2, when the piston string is subjected to the external liquid pressure from the upper coupling, liquid passes through the inner hole and the side hole of the piston rod connected in series and is filled into the annular space enclosed by the outer parts of the three piston rods and the cylinder, at the moment, the four pistons are all subjected to the acting force of a common pressure to push the piston string to move, and the pressure force F on the piston string isString＝Q(SPiston 1+SPiston 2+SPiston 3+SPiston 4) The output of the piston string is a piston 4, and the pressure output by the piston 4 is: qPiston 4＝FString/SPiston 4The pressure output by the piston 4 is more than 3 times greater than the pressure input to the system.
Fig. 4 is a schematic diagram of a valve structure of a hydraulic pressure doubling injector.
The valve part as shown in fig. 4 is an important part of the present invention; the cross core body is assembled in the lower coupling of the cylinder barrel according to the figure, the hole on the side surface of the cross core body is opposite to the hole on the side surface of the lower coupling of the cylinder barrel, and then the cross core body and the cylinder barrel are welded together by electric welding to form 2 channels of liquid inlet and liquid outlet which are mutually crossed but not communicated.
Fig. 4 shows two valves, and the liquid inlet valve is composed of an oil inlet cover plug, a liquid inlet valve cover, a ball mop, a valve ball, a valve seat and a spring; the liquid outlet valve is composed of a ball mop, a valve ball, a valve seat, a spring, an oil outlet cover plug and an oil outlet cover; liquid inlet working state: the liquid with pressure outside passes through the side hole of the lower coupling of the cylinder barrel from the outside, the valve ball and the ball puller are pushed up through the side hole and the central hole of the crossed core body and the valve seat, the spring is compressed, and the liquid enters the upper space of the liquid outlet valve through the side hole of the liquid inlet valve cover; when the liquid enters the working state, the liquid outlet valve is closed; and (3) liquid outlet working state: when the liquid pressure stored in the upper space of the liquid outlet valve is greater than the liquid pressure in the lower space of the liquid outlet valve, the liquid pressure pushes the valve ball and the ball drags of the liquid outlet valve, the spring is compressed, and the liquid enters the lower space of the liquid outlet valve through the side hole of the oil outlet cover; when the liquid is discharged in a working state, the liquid inlet valve is closed.
As can be seen from fig. 1, the piston string system of fig. 3 is independent in the cylinder system of fig. 1, there is no rigid connection between the two, only oil-tight contact is made through the seals, and the resistance force is only friction.
The piston string system can reciprocate in the cylinder system, and the travel of the movement is the length of the cylinder minus the length of the piston.

Claims (8)

1. A hydraulic pressure-multiplying injector is characterized by comprising a cylinder barrel system, a piston string system and a valve structure; the piston string system is arranged in the cylinder barrel system, and the valve structure is arranged at the other end of the cylinder barrel system.
2. The hydraulic pressure doubling injector according to claim 1, wherein the cylinder system is a cylinder group in which hydraulic cylinders are connected in series, the cylinder group comprises N cylinders, a cylinder upper coupling, an operation nipple, an upper coupling, a cylinder lower coupling and a tail end cylinder, two ends of the cylinder group are respectively fixed by the upper coupling and the lower coupling, and the upper coupling is connected with the head end cylinder through the operation short circuit; the N cylinder barrels are fixedly connected through a cylinder barrel coupling, two ends of the inside of the cylinder barrel coupling are respectively provided with an oil seal and an oil seal pressing cap, and the oil seal is used for ensuring that the piston rod and the cylinder barrel coupling are sealed; the lower part of the tail end cylinder barrel is provided with a central hole; two piston rod guide rings are arranged in the central hole, and the guide rings are used for righting the piston rod and preventing the piston rod from being damaged due to friction between the piston rod and the inner hole of the cylinder coupling.
3. The hydraulic pressure doubling injector of claim 1, wherein the piston string system comprises N pistons, one piston rod by N, including a piston, a piston oil seal, a piston rod, a piston guide ring, a head end piston, and a piston oil seal pressure cap; two ends of each of the N pistons are respectively provided with a piston oil seal and a piston oil seal pressing cap, and the piston oil seals are used for ensuring the sealing between the pistons and the cylinder barrels; except the first-end piston, the other pistons are provided with holes in the axial direction, so that the piston string is communicated with the inner holes to form a whole and moves together when working; the piston rod is provided with through holes in the axial direction, and the lower end of the piston rod is provided with through holes vertical to the axis, so that a hydraulic passage is formed; and the outer sides of the N pistons are provided with piston guide rings for righting the pistons and avoiding direct contact friction between the pistons and the cylinder barrel.
4. The hydraulic pressure doubling injector according to claim 1, wherein the piston string is disposed in a cylinder system, and when the piston string is subjected to external fluid pressure from the inside of the upper coupling, fluid fills an annular space defined by the outside of each piston rod and the cylinder through the inner hole and the side hole of the piston rod connected in series, and the N pistons are all subjected to a common pressure force to push the piston string to move, and the pressure force applied to the piston string
FString＝Q(SPiston N1+SPiston N2+SPiston N3+SPiston N4)
The output of the piston string is piston N4, and the pressure output by piston N4 is:
Qpiston N4＝FString/SPiston N4
The pressure output by the piston is more than 3 times greater than the pressure input by the system; after the liquid with the ultrahigh pressure of more than 3 times is output, the liquid is directly extruded into an oil layer, the compact oil layer in a near well zone is forced to be pressed open and crushed, a plurality of cracks are extruded open, the original stratum structure is changed, the liquid is like a small fracturing effect, the flow conductivity of the oil layer is improved, and the yield of an oil well or the injection amount of a water well is improved.
5. The hydraulic pressure multiplier injector of claim 1, wherein the valve structure is fitted within the bore lower collar, the valve structure comprising a crossed core and two valve balls.
6. The hydraulic pressure multiplier injector of claim 5, wherein said crosscore is welded within the lower collar of the cylinder; the side face of the crossed core body is provided with a hole corresponding to the side face hole of the lower coupling of the cylinder barrel, and two channels of liquid inlet and liquid outlet which are mutually crossed but not communicated are formed.
7. The hydraulic pressure multiplier injector of claim 5, wherein said two valve balls are respectively disposed at both ends of the cross-core by a ball-drag and a valve seat.
8. The hydraulic pressure-multiplying injector according to claim 5, wherein the valve ball at the front end of the crossed core passes through a liquid inlet valve cover, and the liquid inlet valve is formed by a liquid inlet cover plug and a spring; the valve ball at the tail end of the crossed core body forms an oil outlet valve through an oil outlet valve plug, an oil outlet valve cover and a spring.
CN201911058736.3A 2019-10-24 2019-10-24 Hydraulic pressure-multiplying injector Pending CN112709559A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911058736.3A CN112709559A (en) 2019-10-24 2019-10-24 Hydraulic pressure-multiplying injector

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911058736.3A CN112709559A (en) 2019-10-24 2019-10-24 Hydraulic pressure-multiplying injector

Publications (1)

Publication Number Publication Date
CN112709559A true CN112709559A (en) 2021-04-27

Family

ID=75541144

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911058736.3A Pending CN112709559A (en) 2019-10-24 2019-10-24 Hydraulic pressure-multiplying injector

Country Status (1)

Country Link
CN (1) CN112709559A (en)

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WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20210427

WD01 Invention patent application deemed withdrawn after publication