CN209784080U - rock core test device for high-temperature high-pressure triaxial and hydraulic fracturing tests - Google Patents

Abstract

the utility model relates to a rock core test device for high temperature high pressure triaxial and hydraulic fracturing, by top toper screw thread end cap, dismantle the auxiliary hole, O type sealing washer, movable bolt circle, the barrel, the top cushion, the heating resistor silk, the cavity, the rock specimen, high-elastic rubber sleeve, the bottom cushion, the steckel, the axial plunger, axial thread guide rail, lead the oilhole, central water guiding hole, the condenser pipe, thermal-insulated protective layer, the heat transfer cooling chamber, servo hydraulic press, the bolt, restraint groove, the high-pressure cross valve, the hydraulic pump, the confining pressure pump, lift controller, the oil tank, computer system and high-pressure ball valve constitute. The test device has the advantages of simple structure, convenience in disassembly, good sealing performance, capability of quickly replacing the rock core, capability of testing mechanical properties of different rock cores under various temperature and pressure conditions according to scientific research and production requirements, and high-efficiency and reliable work including rock core triaxial test and hydraulic fracturing test.

Description

Rock core test device for high-temperature high-pressure triaxial and hydraulic fracturing tests

Technical Field

The utility model relates to a test device, concretely relates to rock core test device for high temperature high pressure triaxial and hydraulic fracturing.

Background

The hot dry rock is used as a new energy source, has the advantages of large reserves, wide distribution range, cleanness, no pollution and the like, and has attracted the attention of scientific research personnel. However, the heat energy exchange of the hot dry rock is complicated because the buried depth of the hot dry rock is large, the permeability of a reservoir is low, and the ground stress is high. Therefore, reservoir stimulation is often needed, namely, high-pressure fluid is injected into the deep dry hot rock body through a drilling hole, so that the fracture is subjected to shear failure or tension failure, and therefore an artificially modified reservoir with larger opening, longer fracture radius and higher permeability is formed, and the deep dry hot rock heat energy extraction efficiency is improved. However, in order to further elucidate the hydraulic fracturing mechanism of the deep rock mass and the failure mechanism under the triaxial stress state, indoor simulation of high-temperature and high-pressure hydraulic fracturing and triaxial core tests must be performed to obtain various physical property parameters of the core, so as to reflect the relevant characteristics of the deep underground rock mass. Corresponding test devices were subsequently developed for carrying out the simulation tests.

at present, the key technology for hydraulic fracturing and triaxial tests of simulated rock cores under high-temperature and high-pressure conditions lies in the tightness and convenience of a test device. The tightness of the test device is related to the accuracy of simulating high-pressure conditions, and the test device with good tightness can not only meet the pressure conditions of deep underground rock masses, but also improve the completion efficiency of the test; because the high temperature high pressure requirement of test condition, the convenience of test device receives the restriction at to a great extent, not only need consider high temperature resistant, also need consider high pressure resistant for most relevant test instrument dismantlement process is complicated, and high temperature oil cooling time is long, and the test cycle is slow. Therefore, an efficient and quick high-temperature and high-pressure core testing device is needed to complete related testing work.

Disclosure of Invention

The utility model discloses the purpose just lies in to above-mentioned prior art not enough, provides a rock core test device for high temperature high pressure triaxial and hydraulic fracturing, can realize rock core test sample quick replacement, and the high temperature oil body cools off fast shortens the rock core test cycle, improves work efficiency, accomplishes rock core triaxial and hydraulic fracturing test under the high temperature high pressure condition according to the demand.

the utility model aims at realizing through the following technical scheme:

A rock core test device for high-temperature high-pressure triaxial and hydraulic fracturing comprises a top conical threaded plug, a disassembly auxiliary hole, an O-shaped sealing ring, a movable bolt ring, a barrel, a top cushion block, a heating resistance wire, a cavity, a rock sample, a high-elastic rubber sleeve, a bottom cushion block, a Stent seal, an axial plunger, an axial threaded guide rail, an oil guide hole, a water guide hole, a condensation pipe, a heat insulation protective layer, a heat exchange cooling chamber, a servo hydraulic machine, a bolt, a restraint groove, a high-pressure four-way valve, a hydraulic pump, a confining pressure pump, a lifting controller, an oil tank, a computer and a high-pressure ball valve.

And the threaded plug, the barrel and the axial plunger enclose a cavity, and the cavity is filled with the dimethyl silicone oil. The threaded plug is connected with the barrel through a conical thread, four restraining grooves are poured around the threaded plug, the movable bolt ring is nested on the barrel through interference fit, and the threaded plug is restrained through the four bolt-fit restraining grooves connected with the movable bolt ring. The disassembly auxiliary hole is poured on the threaded plug. The threaded plug is plugged at the upper part of the cavity, and the center of the threaded plug is provided with a water guide hole connected with the high-pressure ball valve for providing a water pressure channel and leading out water flow. The edge is provided with an oil guide hole, and a disassembly auxiliary hole is poured on the oil guide hole; the high-pressure ball valve is respectively connected with the water pressure pump and the oil tank, and the oil tank is also connected with the condensing tube and a high-pressure four-way valve connected with the confining pump. The condenser pipe is a coil pipe with the diameter ofThe oil liquid in the cylinder body enters the condensing tube to be cooled.

the improved cylindrical heating device is characterized in that two O-shaped rubber rings are arranged on a platform surface at the top of the cylindrical shell, a steckel seal matched with double rows of axial plungers to seal the lower part of the cavity is arranged on the wall surface of an inner ring of an opening at the lower part, heating resistance wires are arranged in the cylindrical shell and are arranged in the cylindrical shell in a multi-row quincuncial pile mode, and the heating resistance wires are connected with a. The cylinder body is respectively connected with the threaded axial guide rail, the condensation pipe, the hydraulic pump and the confining pressure pump. The confining pressure pump and the water pressure pump are respectively connected with the pressure sensor. The barrel is made of a high-rigidity rigid material, four convex blocks are arranged at the lower end opening of the barrel, a threaded hole is formed in the center of each block, the barrel is connected to the axial threaded guide rail through the threaded hole, and the barrel is controlled to ascend and descend through the axial threaded guide rail. The top end of the axial threaded guide rail is provided with a convex block and four guide rail columns with large rigidity, wherein two diagonal columns are threaded columns, and the other two diagonal columns are constraint columns.

the axial plunger is connected with the servo hydraulic press in a control mode, the servo hydraulic press is used for controlling ascending and descending and applying axial pressure to the rock sample, the axial plunger is connected with the displacement sensor, and the displacement of the axial plunger is controlled by the displacement sensor. The servo hydraulic machine is externally provided with a heat insulation protective layer which is composed of asbestos and is closely attached to the inner wall of the heat exchange cooling chamber in an annular shape.

the cavity is internally provided with a high-elasticity rubber sleeve, and a top cushion block fixed with the threaded plug, a bottom cushion block fixed with the axial plunger and a rock sample positioned between the top cushion block and the bottom cushion block are arranged in the high-elasticity rubber sleeve. The top cushion both ends center is equipped with the stand pipe, and the stand pipe top in upper portion is equipped with the bulb and is protruding, and there is the toper sealing cap on the protruding surface of bulb to on being connected to top cushion upper landing face through high strength spring, be equipped with two O type circles on the upper landing face, the stand pipe embedding screw plug lower extreme in upper portion, the stand pipe shaft of the protruding pipe in lower part is equipped with two O type circles, and embedding rock specimen axle center. The lower part of the bottom cushion block is connected with a convex pipe, the upper part of the bottom cushion block is provided with a concave groove, and the filtering gasket is nested in the bottom cushion block. The sample is sleeved in the high-elasticity rubber sleeve according to the sequence of the top cushion block, the rock sample and the bottom cushion block, and is integrally placed in the cavity. The O-shaped rubber ring is embedded in the two circular grooves on the platform surface at the top of the cylinder body; the steckel seal is embedded into two circular grooves on the inner wall surface of the opening at the lower end of the cylinder body; the O-shaped rubber ring, the tapered thread and the steckel seal are all sealing devices.

And the heating resistance wire, the confining pressure pump, the hydraulic pump and the lifting controller in control connection with the threaded axial guide rail are respectively connected with the computer. The pipeline is controlled to open and close by a high-pressure ball valve; the hydraulic pump and the confining pressure pump respectively provide water pressure and confining pressure for the rock sample, and the load is controlled through the sensor.

further, the disassembly assisting hole can be inserted into the rod-shaped disassembly equipment so as to increase the torque to open or close the conical threaded plug at the top.

Furthermore, the threaded axial guide rails are distributed diagonally, and the top ends of the guide rails are provided with bumps to restrict the barrel from moving upwards and provide reaction force for the barrel.

Further, the amount of axial plunger travel has a limit to prevent disengagement from the stent.

furthermore, the length of the cavity has a certain range, the size of the range is determined by the axial plunger, and tests can be provided for core samples with different lengths.

Furthermore, the top cushion block and the top cushion block can be replaced according to different tests.

Further, the rock specimen is cylindric test piece, can use the square rock specimen of small dimension under the condition of changing the cushion.

Furthermore, the condensing pipe is connected with the cylinder body, the confining pressure pump is connected with the cylinder body, the water pressure pump is connected with the cylinder body through a portable high-temperature high-pressure hose, and the oil tank is connected with the high-pressure four-way valve through a common hose.

Compared with the prior art, the beneficial effects of the utility model reside in that: 1. adopt toper screw thread end cap, this rock core test device simple structure, easy dismounting. 2. And the axial threaded guide rail is adopted to realize rapid lifting of the cylinder. 3. The condensing tube is matched with the heat exchange cooling chamber to quickly condense high-temperature oil, so that the test period is greatly shortened, and the test efficiency is improved. 4. And a movable bolt ring is adopted, so that the restraint angle can be conveniently adjusted. 5. The axial plunger is adopted to control the height of the barrel body in a lifting way, so that the core test piece within a certain length range can be tested, and diversified test requirements are met. 6. The top cushion block and the bottom cushion block are adopted, and two or more test pieces with regular shapes, particularly cylindrical and square test pieces can be tested by replacing different cushion blocks.

Drawings

FIG. 1 is a schematic cross-sectional front view of a core testing apparatus that may be used for high temperature, high pressure, triaxial and hydraulic fracturing;

FIG. 2 is a perspective view of a threaded guide device;

FIG. 3 is a top view of the top tapered threaded plug;

FIG. 4 is a schematic plan view of a movable bolt ring;

FIG. 5 is a schematic view of the top pad;

FIG. 6 is a schematic view of the bottom block;

FIG. 7 is a top view of the arrangement of the condenser tubes;

FIG. 8 is a partial plan view of the condenser tube;

In the figure: 1. the screw plug 2, the disassembly auxiliary hole 3, the O-shaped rubber ring 4, the movable bolt ring 5, the barrel 6, the top cushion block 7, the heating resistance wire 8, the cavity 9, the rock sample 10, the high-elastic rubber sleeve 11, the bottom cushion block 12, the steckel 13, the axial plunger 14, the axial threaded guide rail 15, the oil guide hole 16, the water guide hole 17, the high-pressure ball valve 18, the condenser pipe 19, the heat insulation protective layer 20, the heat exchange cooling chamber 21, the servo hydraulic machine 22-the bolt 23, the restraint groove 24, the high-pressure four-way valve 25, the hydraulic pump 26, the confining pressure pump 27, the lifting controller 28, the oil tank 29, the computer 30, the conical sealing cap 31, the high-strength spring 32, the O33, the filter gasket 34 and the.

Detailed Description

The drawings in the examples of the present invention will be described below to describe the technical solutions in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

As shown in fig. 1 and 2, a core test device for high-temperature high-pressure triaxial and hydraulic fracturing comprises a top tapered threaded plug 1, a disassembly auxiliary hole 2, an O-shaped rubber ring 3, a movable bolt ring 4, a cylinder 5, a top cushion block 6, a heating resistance wire 7, a cavity 8, a rock sample 9, a high-elastic rubber sleeve 10, a bottom cushion block 11, a steckel seal 12, an axial plunger 13, an axial threaded guide rail 14, an oil guide hole 15, a water guide hole 16, a high-pressure ball valve 17, a condenser pipe 18, a heat insulation protective layer 19, a heat exchange cooling chamber 20, a servo hydraulic machine 21, a bolt 22, a restraint groove 23, a high-pressure four-way valve 24, a hydraulic pump 25, a confining pressure pump 26, a lifting controller 27, an oil tank 28 and a computer. The top conical thread plug 1 is connected to the barrel 5 through a movable bolt ring 4 and a conical thread; the cylinder 5 is connected through a threaded axial guide rail 14, and the maximum displacement is limited through a convex block at the top end of the threaded axial guide rail 14; the rock sample 9 is clamped by the top cushion block 6 and the bottom cushion block 11 under the same stress, and axial pressure is applied to the rock sample by the axial plunger 13, and confining pressure is applied to the rock sample by moving oil; the oil tank 28 is connected to the high-pressure ball valve 17 through a hose to fill the cavity 8 with oil; the high-pressure four-way valve 24 opens the confining pressure valve, closes the oil outlet valve, and is connected with the confining pressure pump 26 through a high-pressure hose for pressurization or pressure relief; high-temperature oil flows into a condenser pipe 18 from the cavity 8 through a high-pressure ball valve 17; the high-pressure ball valve 17 is connected with a hydraulic pump 21 and applies water pressure to the rock sample through the central water guide hole 16; the heating resistance wire 7 is connected with a computer 29 through a line, and the heating oil is controlled by the computer.

As shown in fig. 3, four constraining grooves 23 are poured around the threaded plug 1 to cooperate with the bolts 22 to constrain axial displacement;

as shown in fig. 4, the movable bolt ring 4 is connected with four bolts 22, and the top threaded plug 1 is restrained by matching with a restraining groove 23;

as shown in fig. 5, the centers of the two ends of the top cushion block 6 are provided with convex pipes, the top end of the upper convex pipe is provided with a spherical convex, the surface of the spherical convex is provided with a conical sealing cap 30 and is connected to the upper platform surface of the top cushion block 6 through a high-strength spring 31, the upper platform surface is provided with two O-rings 32, the upper convex pipe is embedded into the lower end of the threaded plug 1, and the pipe body of the lower convex pipe is provided with two O-rings 32 and is embedded into the axle center of the rock sample 9 to implement the hydraulic fracturing test.

As shown in fig. 6, the lower part of the bottom cushion block 11 is connected with a convex pipe, the upper part is provided with a concave groove 34, and a filtering gasket 33 is nested in the bottom cushion block 11 and collects water flow through a filtering hole;

as shown in fig. 7 and 8, the condensation pipe 18 is a coil pipe and is annularly disposed in the cooling chamber 20, and the cooling chamber 20 cools the condensation pipe through water flow.

Example 1

hydraulic fracturing examples

step 1, processing a rock core, wherein the rock core is processed into a cylindrical shape through a rock sample cutting machine, and the axis of the rock core is provided with a water guide hole with a certain depth;

Step 2, carrying out core clamping outside the cavity 8, respectively placing a top cushion block 6, a rock sample 9 and a bottom cushion block 11 according to the sequence of up, middle and down, and sleeving the top cushion block, the rock sample 9 and the bottom cushion block in a high-elasticity rubber sleeve 10, wherein the upper end and the lower end of the sleeve can be sealed by using a fastening device;

Step 3, disassembling the auxiliary hole 2 by using a rod-shaped device in a matching manner, rotating the conical threaded plug 1 at the top, and opening an upper opening of the cylinder 5;

step 4, opening the computer 29, controlling the lifting controller 27 to enable the barrel 5 to descend along the threaded axial guide rail 14 until the top end of the axial plunger 13 rises to the opening of the barrel 5;

step 5, inserting the clamped high-elasticity rubber sleeve 10 into the water guide hole 16 by using a lower convex pipe of the bottom cushion block 11, and fixing a sample;

Step 6, lifting the barrel 5 to a limit position, screwing the top conical thread plug 11, rotating the movable bolt ring 4 to restrain the slot, and finally screwing the bolt 22;

and 7, starting the servo hydraulic machine 21, connecting the computer 29 with a pressure sensor to control the pressure, pushing the axial plunger 13 to move upwards, and applying a certain axial pressure to the rock core in advance.

step 8, connecting an oil tank 28 to a high-pressure ball valve III 17 and a high-pressure four-way valve 24 by using a hose, feeding oil into the high-pressure ball valve III 17 through the oil tank 28, and discharging oil from the high-pressure four-way valve 24 until the cavity is completely filled with oil;

And 9, closing other high-pressure ball valves, closing an oil outlet valve of the high-pressure four-way valve 24, switching on a power supply of the heating resistance wire 7 to heat the oil, controlling the heating temperature to the experimental temperature by using the computer 29, and not executing heating operation under the normal temperature condition.

step 10, opening a confining pressure valve, and applying confining pressure to the cavity by using a confining pressure pump 26 of a computer system;

Step 11, closing the high-pressure four-way valve 24, connecting the hydraulic pipe to a hydraulic pump 25 and a high-pressure ball valve 17, and applying water pressure to the rock sample 9 by using the hydraulic pump 25 until the rock sample 9 is damaged;

Step 12, after the test is finished, opening a confining pressure valve of the high-pressure four-way valve, and withdrawing the pump by using a confining pressure pump 26 to discharge the confining pressure to the normal pressure;

Step 13, connecting a high-temperature hose to the condenser pipe 18, opening a high-pressure ball valve II 17, allowing high-temperature oil to enter the condenser pipe 18, cooling in the condenser pipe 18, and returning to the oil tank 28;

And step 14, opening the conical threaded plug 11 at the top, descending the barrel, taking out the rock sample, processing data, and performing the next rock sample test.

Example 2

High temperature high pressure triaxial embodiment

Replacing the common cushion block without applying water pressure, repeating the steps of the hydraulic fracturing embodiment, and pushing the axial plunger 13 by using the servo hydraulic machine 21 to apply pressure until the rock sample 9 is damaged.

Claims (10)

1. the utility model provides a rock core test device for high temperature high pressure triaxial and hydraulic fracturing test which characterized in that: the device comprises a cavity (8) enclosed by a conical threaded plug (1), a barrel (5) connected with the threaded plug (1) and an axial plunger (13), wherein the cavity (8) is filled with dimethyl silicone oil;

The threaded plug (1) is plugged at the upper part of the cavity (8), the center of the threaded plug is provided with a water guide hole (16) connected with a high-pressure ball valve (17), the edge of the threaded plug is provided with an oil guide hole (15), and a disassembly auxiliary hole (2) is poured on the threaded plug; the high-pressure ball valve (17) is respectively connected with a hydraulic pump (25) and an oil tank (28), and the oil tank (28) is also connected with a condensing pipe (18) and a high-pressure four-way valve (24) connected with a confining pump (26);

Two O-shaped rubber rings (3) are arranged on a platform surface at the top of the barrel body (5), a double-row matched axial plunger (13) is arranged on the inner ring wall surface of the lower opening to seal a steckel seal (12) at the lower part of the cavity (8), and a heating resistance wire (7) is arranged in the barrel body (5); the cylinder body (5) is respectively connected with the axial threaded guide rail (14), the condenser pipe (18), the hydraulic pump (25) and the confining pressure pump (26);

the axial plunger (13) is in control connection with a servo hydraulic machine (21);

a high-elasticity rubber sleeve (10) is arranged in the cavity (8), and a top cushion block (6) fixed with the threaded plug (1), a bottom cushion block (11) fixed with the axial plunger (13) and a rock sample (9) positioned between the top cushion block (6) and the bottom cushion block (11) are arranged in the cavity;

The heating resistance wire (7), the surrounding pressure pump (26), the water pressure pump (25) and the lifting controller (27) which is in control connection with the axial threaded guide rail (14) are respectively connected with the computer (29).

2. The core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: four restraining grooves (23) are poured around the threaded plug (1), the movable bolt ring (4) is nested on the barrel body (5) in an interference fit mode, and the four bolts (22) connected with the movable bolt ring are matched with the restraining grooves (23) to restrain the threaded plug (1).

3. The core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: the barrel (5) is made of a high-rigidity rigid material, four convex blocks are arranged at the lower end opening of the barrel, a threaded hole is formed in the center of each block, and the barrel (5) is connected to the axial threaded guide rail (14) through the threaded hole.

4. the core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 3, wherein: the top end of the axial threaded guide rail (14) is provided with a convex block and four guide rail columns with large rigidity, wherein two diagonal columns are threaded columns, and the other two diagonal columns are constraint columns.

5. The core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: the heating resistance wires (7) are arranged in the cylinder body (5) in a multi-row quincuncial pile manner.

6. The core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: the axial plunger (13) is connected with a displacement sensor, the surrounding pressure pump (26) and the water pressure pump (25) are respectively connected with a pressure sensor, and the heating resistance wire (7) is connected with a temperature sensor.

7. The core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: the center of top cushion (6) both ends is equipped with the bulge tube, and the bulge tube top in upper portion is equipped with the ball and protrudes, and the protruding surface of ball has toper sealing cap (30) to be connected to top cushion (6) upper landing face through high strength spring (31) on, be equipped with two O type circle (32) on the upper landing face, upper portion bulge tube embedding screw plug (1) lower extreme, the bulge tube body in lower part is equipped with two O type circle (32), and embedding rock specimen (9) axle center.

8. The core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: the condensation pipe (18) is a coil pipe with the diameter ofAre connected in series in the heat exchange cooling chamber (20) in a ring shape.

9. the core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: the lower part of the bottom cushion block (11) is connected with a convex pipe, the upper part of the bottom cushion block is provided with a concave groove (34), and a filtering gasket (33) is embedded in the bottom cushion block (11).

10. The core test device for the high-temperature high-pressure triaxial and hydraulic fracturing test according to claim 1, wherein: and a heat insulation protective layer (19) consisting of asbestos is arranged outside the servo hydraulic press (21) and clings to the inner wall of the heat exchange cooling chamber (20) in an annular shape.