Pressure channel change-over valve for hydraulic test and fracturing crack impression system

Abstract

The utility model discloses a hydraulic test pressure channel change-over valve and a fracturing crack impression system, comprising a valve body, one end of the valve body is connected with a drill rod, the other end of the valve body is connected with an impression device, the valve body is provided with a hollow cavity, the side wall of the valve body is provided with a water inlet hole used for being communicated with an inner cavity of the impression device, and the water inlet hole is also communicated with the cavity; the packing piston comprises a piston base body which is provided with an axial through hole and can be arranged in the cavity of the valve body in a sliding manner, a limiting releasing device arranged on the inner wall of the piston base body and a piston spearhead which is clamped in the axial through hole by the limiting releasing device, and the axial through hole is communicated with the central through hole of the impression device; the limiting releasing device is arranged in the mode that in the initial state, the piston spearhead is clamped in the axial through hole of the piston base body through the limiting releasing device, and when the limiting releasing device is pressed to move towards the impression device to the limiting position, limitation on the piston spearhead is released. According to the utility model, waterways can be switched as required.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of rock mass mechanics test, specifically relates to a pressure channel conversion valve for hydraulic test and fracturing fracture impression system. BACKGROUND

[0002] At present, the rope coring drilling technology has been popularized in deep drilling construction. In order to facilitate implementation, the hydraulic fracturing method of ground stress test often needs to use the rope coring drill rod, and the conventional hydraulic fracturing method of ground stress test mainly includes two steps: first, the rock mass hydraulic fracturing test is carried out, and a fracturing fracture is formed on the wall of the measured section hole, and the process can obtain the stress value parameter; second, the fracturing fracture of the selected measured section is tested, and the stress direction of the corresponding measuring point can be obtained according to the trace of the soft rubber layer of the rubber plug surface layer extruded into the hole wall fracture combined with the directional device. The drill rod and the drilling machine need to be matched in the test process, the hydraulic fracturing test can complete the whole hole measurement by drilling once, but the existing impression test technology generally only obtains the data of one measuring point by drilling each time, and needs to be tested repeatedly, which consumes a lot of time. Therefore, it is of great significance to invent a pressure channel conversion valve for hydraulic test and a fracturing fracture impression device which can reduce the number of drilling. SUMMARY

[0003] One purpose of the utility model is to solve the problems of the prior art, provide a pressure channel conversion valve for hydraulic test, the device can switch the waterway according to the needs, so that the two-section fracturing fracture impression test can be completed by drilling once, and the test time, manpower and material consumption can be effectively reduced.

[0004] To solve the above technical problems, the technical scheme adopted by the present application is as follows:

[0005] A pressure channel conversion valve for hydraulic test, comprising:

[0006] A valve body, one end of which is connected with a drill rod, and the other end of which is connected with an impression device, the valve body has a cavity, a water inlet hole for connecting the inner cavity of the impression device is arranged on the side wall of the valve body, and the water inlet hole is also connected with the cavity;

[0007] A packer piston, the packer piston comprises a piston base body having an axial through hole and being slidably arranged in the cavity of the valve body, a limit releasing device arranged on the inner wall of the piston base body, and a piston spearhead clamped in the axial through hole by the limit releasing device, and the axial through hole is connected with the central through hole of the impression device;

[0008] The limiting releasing device is arranged to clamp the piston lance in the axial through hole of the piston base in the initial state, and the piston lance is pulled to move the sealing piston in the cavity until the maximum stroke is reached, and the piston lance is continuously pulled, and the limiting releasing device is pressed to move to the extreme position in the direction of the impression device to release the limitation of the piston lance, at this time, the piston lance is pulled out of the valve body to communicate the drill pipe, the axial through hole and the central through hole.

[0009] Further, the cavity includes an opening close to the drill pipe and a cavity body communicated with the opening, wherein the inner diameter of the opening is smaller than the inner diameter of the cavity body, and the piston base is slidingly arranged in the cavity body of the valve body, and the outer diameter of the piston base is greater than the inner diameter of the opening, so that the piston base is limited to move in the cavity body.

[0010] Further, the limiting releasing device includes a limiting groove arranged on the end surface of the piston base towards the drill pipe, a spring fixed in the limiting groove, a jack connected with the other end of the spring, and a plurality of through holes arranged on the side wall of the piston base, each through hole is communicated with a limiting groove; a hemispherical lance groove corresponding to each through hole is arranged on the outer side wall of the piston lance, a hemispherical jack groove matched with each lance groove is arranged on the inner side wall of the jack, and a limiting ball is arranged in each lance groove, wherein the radius of the limiting ball is greater than the thickness of the through hole, but the inner diameter of the through hole is not less than the outer diameter of the limiting ball.

[0011] When the spring is in the natural elongation state, the jack extends out of the limiting groove, at this time, the limiting ball in the piston lance is clamped in the lance groove and the through hole to fix the piston lance in the piston base, the piston lance is pulled to move the sealing piston in the cavity of the valve body until the maximum stroke is reached, at this time, the piston base blocks the water inlet hole, the piston lance is continuously pulled, the spring is compressed until the spring is compressed to the shortest, the lance groove, the through hole and the jack groove are aligned, the limiting ball is offset from the lance groove to the jack groove, and the limitation of the piston lance is released and can be slid in the axial through hole.

[0012] Further, the piston lance includes a blocking part, a connecting part and a tapered head part connected in sequence, the blocking part is arranged in the axial through hole of the piston base, and the lance groove is arranged on the outer side wall of the blocking part.

[0013] Further, the tapered head part is tapered with the diameter gradually decreasing away from the impression device.

[0014] Further, the connecting part extends into the drill pipe from the cavity and is connected with the tapered head part, and the maximum outer diameter of the tapered head part is greater than the inner diameter of the end of the cavity close to the drill pipe.

[0015] Further, a plurality of first sealing rings are arranged on the outer wall of the blocking part, and the plurality of first sealing rings are arranged on the side wall of the blocking part below the lance head groove and close to the impression device.

[0016] Further, a plurality of second sealing rings are arranged on the inner wall of the piston base body, and the plurality of second sealing rings are respectively arranged on both sides of the water inlet hole.

[0017] The utility model also provides a fracturing fracture impression system, including pressure channel conversion valve for hydraulic test, the impression device and the electronic compass of setting in impression device end, wherein, the impression device includes first impression ware and second impression ware are connected with each other, first impression ware includes first center tube and first rubber plug of being sleeved on first center tube, and the closed first inner chamber is formed between first rubber plug and first center tube, and second impression ware includes second center tube and second rubber plug of being sleeved on second center tube, and the closed second inner chamber is formed between second rubber plug and second center tube, and first center tube and second center tube are connected in sequence and form the central through -hole of impression device, and first inner chamber is communicated with water inlet hole, and a plurality of water outlet holes are arranged on second center tube, and second inner chamber is communicated with second center tube through a plurality of water outlet holes.

[0018] Compared with the prior art, the utility model has the advantages that: the utility model discloses a pressure channel conversion valve structure is set up ingeniously, when the piston lance head is limited in the piston base body, the high pressure water in the drill rod is communicated with the inner chamber of one impression ware, when the piston lance head is lifted to a certain degree by the fishing tool, the communication channel of one impression ware and the high pressure water in the drill rod can be closed, and the communication channel of the drill rod and the inner chamber of another impression ware is opened, so that two-stage fracturing fracture impression tests can be completed once drilling, the test time, manpower and material consumption can be effectively reduced, the construction cost is greatly reduced, and the construction efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is the different state diagram of the working process of the fracturing fracture impression system of the utility model embodiment, wherein, (a) initial state, (b) the limitation of the piston lance head is removed, (c) after the piston lance head is pulled out.

[0020] Figure 2 It is the structure schematic view of the valve body of the pressure channel conversion valve of the utility model embodiment;

[0021] Figure 3 It is the structure schematic view of the piston base body of the pressure channel conversion valve of the utility model embodiment;

[0022] Figure 4 It is the structure schematic view of the piston lance head of the pressure channel conversion valve of the utility model embodiment. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0024] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0025] The present application will be further described below with reference to specific embodiments, but is not limited to the embodiments.

[0026] The present application discloses a pressure channel conversion valve for hydraulic test, as shown in Figure 1 and Figure 2 , comprising a hollow valve body 31 and a sealing piston arranged in the valve body. One end of the valve body 31 is connected with a drill rod 1, and the other end is connected with an impression device. The valve body 31 has a hollow cavity. In order to facilitate subsequent positioning of the sealing piston, the cavity includes an opening 311 close to the drill rod 1 and a cavity 312 in communication with the opening 311, wherein the inner diameter of the opening 311 is smaller than the inner diameter of the cavity 312 so that the end of the cavity close to the drill rod 1 is closed. A water inlet hole 314 for communicating the inner cavity of the impression device is arranged on the side wall of the valve body 31, and the water inlet hole 314 is in communication with the cavity 312.

[0027] As shown in Figure 3 and Figure 4 , the sealing piston comprises a piston base body 32 having an axial through hole 321 and being slidably arranged in the cavity of the valve body, a position releasing device arranged on the inner wall of the piston base body 32, and a piston spearhead 34 clamped in the axial through hole 321 by the position releasing device. The piston base body 32 is slidably arranged in the cavity 312 of the valve body 31 and can move a certain distance along the inner wall of the valve body 31. The outer diameter of the piston base body 32 is greater than the inner diameter of the opening, so that the piston base body 32 is limited to move in the cavity 312.

[0028] The position releasing device comprises a position limiting groove 331 arranged on the end face of the piston base 32 towards the drill pipe 1, a spring 332 fixed at one end in the position limiting groove 331, a top rod 333 connected with the other end of the spring 332, and a plurality of through holes 334 arranged on the side wall of the piston base 32, each of the through holes 334 being in communication with a position limiting groove 331. A semispherical lance groove is arranged on the outer side wall of the piston lance 34 in alignment with each of the through holes, a semispherical top rod groove 335 is arranged on the inner side wall of the top rod 333 in cooperation with each of the lance grooves, and a position limiting ball 344 is arranged in each of the lance grooves, wherein the radius of the position limiting ball 344 is greater than the thickness of the through hole 334, but the inner diameter of the through hole 334 is not less than the outer diameter of the position limiting ball 341.

[0029] When the spring 332 is in the natural elongation state, the top rod 333 extends out of the position limiting groove 331, at this time, the position limiting ball 341 in the piston lance 34 is clamped in the lance groove and the corresponding through hole 334 to fix the piston lance 34 in the piston base 32, the piston lance 34 is pulled, and the packer moves in the cavity until the maximum stroke is reached, at this time, the piston base 32 blocks the water inlet hole 314. Continue to pull the piston lance 34, the top rod 333 is compressed to compress the spring 332 in the direction of the impression device, when the spring 332 is compressed to the shortest, the lance groove, the through hole 334 and the top rod groove 335 are aligned, the position limiting ball 344 is offset from the lance groove to the top rod groove 335, at this time, the restriction of the position releasing device to the piston lance 34 is released, continue to pull, the piston lance 34 is pulled out, and the drill pipe 1, the axial through hole of the packer and the central through hole of the impression device are sequentially communicated.

[0030] In the embodiment, in order to facilitate clamping one end of the piston lance 34 in the axial through hole of the piston base and facilitating pulling the piston lance 34, the piston lance 34 comprises a blocking part 341, a connecting part 342 and a tapered head part 343 connected in sequence, the blocking part 341 is arranged in the axial through hole 321 of the piston base 32, and the lance groove is arranged on the outer side wall of the blocking part 341. The tapered head part 343 is tapered and gradually decreases in diameter away from the impression device, the connecting part 342 extends from the opening 311 to the drill pipe 1 and is connected with the tapered head part 343, and the maximum outer diameter of the tapered head part 343 is greater than the inner diameter of the opening.

[0031] In order to prevent the water in the drill pipe 1 from leaking into the center through hole of the mold device from the gap between the blocking part 341 and the inner wall of the piston base 32, a plurality of first sealing rings 345 are arranged on the outer wall of the blocking part 341, which are arranged below the lance groove of the blocking part 341 and close to the side wall of the mold device. In addition, in order to prevent the water in the drill pipe 1 from leaking into the water inlet hole from the gap between the piston base 32 and the inner wall of the valve body 31 when the piston base 32 blocks the water inlet hole 314, a plurality of second sealing rings 313 are arranged on the inner wall of the piston base 32, which are respectively located on both sides of the water inlet hole 314. The system device comprises the pressure channel switching valve for hydraulic testing, the mold device and the electronic compass 6 arranged at the end of the mold device. The mold device comprises the first mold 4 and the second mold 5 connected in series, which are connected through the drill pipe and the mold connector 51, and the length of the drill pipe is determined by the distance between the two measuring sections. The first mold 4 is connected with the end of the valve body 31 through the first connector 41. The first mold 4 comprises the first center pipe 43 and the first rubber plug 42 sleeved on the first center pipe 43, and the first inner cavity 44 is formed between the first rubber plug 42 and the first center pipe 43. The second mold 5 comprises the second center pipe 53 and the second rubber plug 52 sleeved on the second center pipe 53, and the second inner cavity 54 is formed between the second rubber plug 52 and the second center pipe 53. The first center pipe 43 and the second center pipe 53 are sequentially connected to form the center through hole of the mold device, the first inner cavity 44 is communicated with the water inlet hole 314, and a plurality of water outlet holes 55 are arranged on the second center pipe 53, and the second inner cavity 54 is communicated with the second center pipe 53 through the plurality of water outlet holes 55.

[0032] The fracture print mold system is used to obtain fracture occurrence information, and specifically includes the following steps:

[0033] Firstly, the drill pipe 1, the pressure channel switching valve 3, the first mold 4 and the second mold 5 are sequentially connected according to the depth of the first measuring section in the borehole, wherein the first measuring section corresponds to the first mold 4, and the first mold 4 is lowered into the borehole to the position of the fracture of the first measuring section through the drill pipe. Water is injected into the drill pipe 1 for a period of time, high-pressure water enters the first inner cavity 44 of the first mold 4 through the cavity of the pressure channel switching valve and the water inlet hole 314, the first rubber plug 42 absorbs water in the first inner cavity 44 to expand and tightly adhere to the borehole wall and make the fracture open, the soft rubber layer on the surface of the first rubber plug 42 will be squeezed into the fracture of the borehole wall to leave a trace, and the corresponding time period of pressure is recorded. At this time, the working state is as shown in Figure 1 (a);

[0034] Second step, the water in the drill pipe 1 is extracted to unload the pressure in the first impression ware 4, the wire rope is put into the rope core coring fish 2 through the winch device connection, is lowered to the fish 2 and is caught the piston lance 34, the fish 2 is lifted, the limiting ball 341 is stuck in the piston base body 32, the fish 2 is lifted, the fish 2 is driven by the piston lance 34 and moves upwards, when the barrier piston moves to the maximum stroke in the cavity, the piston base body 32 seals the water inlet hole 314 at this time. Figure 1 (b) shown, continue to pull, the piston lance 34 is completely pulled out from the piston base body 32, the axial through hole of the drill pipe 1, the piston base body 32, the first central tube 43 and the second central tube 53 are communicated at this time, and the water inlet hole 314 is sealed at this time, the pressure water enters the second inner cavity 54 of the second impression ware 5 from the drill pipe 1, the axial through hole 321, the first central tube 43, the second central tube 53 and the water outlet hole 55, and the working state is as shown in Figure 1 (c) shown;

[0035] Third step, according to the depth of the second measuring section in the borehole, the drill pipe 1 in the borehole is increased or reduced in turn, the second measuring section corresponds to the second impression ware 5, the second impression ware 5 is placed in the borehole corresponding to the position of the second test section fracture through the drill pipe, water is injected into the second inner cavity 54 for a period of time, the second rubber plug 52 absorbs water and expands and makes the fracture open, and the soft rubber layer on the surface of the second impression ware rubber plug 52 retains marks, and the corresponding time period of pressure is recorded.

[0036] Fourth step, the water pressure is unloaded to remove the device in the borehole, the surface continues to keep the device connection state, the electronic compass orientation device 6 is opened, the relative angles of the first impression ware rubber plug 42 retained marks, the second impression ware rubber plug 52 retained marks and the reference line are recorded respectively, the data in the electronic compass 6 is read, the azimuth data recorded by the first section and the second section impression corresponding to the pressure time period are found out respectively, and the occurrence information corresponding to the two fractures can be converted through the relative relationship among the retained marks, the reference line and the azimuth data.

[0037] The utility model can greatly save time, reduce the risk of pulling out the drill, and further produce obvious economic benefits, improve the efficiency of drilling test, reduce the test cost, and the method is simple to operate, the equipment requirement is lower, and it is convenient for large-scale popularization and application.

[0038] The above merely describes preferred embodiments of the present application, and is not intended to limit the implementation and protection scope of the present application. For those skilled in the art, it should be understood that any equivalent substitutions and obvious changes made according to the content of the present application should be included in the protection scope of the present application.

Claims

1. A pressure conduit changeover valve for hydraulic testing, characterised in that, The valve body is connected with the drill pipe at one end and connected with the impression device at the other end, and has a cavity in the middle. A water inlet hole is arranged on the side wall of the valve body and is in communication with the cavity and the inner cavity of the impression device. The sealing piston comprises a piston base body having an axial through hole and being slidably arranged in the cavity of the valve body, a position releasing device arranged on the inner wall of the piston base body, and a piston lance head clamped in the axial through hole by the position releasing device and in communication with the central through hole of the impression device. The position releasing device is arranged to clamp the piston lance head in the axial through hole of the piston base body in the initial state. When the piston lance head is pulled, the piston lance head drives the sealing piston to move in the cavity until the maximum stroke is reached. When the piston lance head is continuously pulled, the position releasing device is pressed to move to the limit position in the direction of the impression device, and the restriction of the piston lance head is released. At this time, the piston lance head is pulled out of the valve body to connect the drill pipe, the axial through hole and the central through hole. The cavity comprises an opening near the drill pipe and a cavity in communication with the opening. The inner diameter of the opening is smaller than the inner diameter of the cavity. The piston base body is slidably arranged in the cavity of the valve body. The outer diameter of the piston base body is greater than the inner diameter of the opening, so that the piston base body is limited to move in the cavity.

2. The pressure conduit switching valve for hydraulic testing according to claim 1, characterized in that The position releasing device comprises a limiting groove arranged on the end face of the piston base body towards the drill pipe, a spring fixed in the limiting groove at one end, a jack connected with the other end of the spring, and a plurality of through holes arranged on the side wall of the piston base body, each through hole being in communication with a limiting groove. A hemispherical lance groove corresponding to each through hole is arranged on the outer side wall of the piston lance head. A hemispherical jack groove corresponding to each lance groove is arranged on the inner side wall of the jack. A limiting ball is arranged in each lance groove. The radius of the limiting ball is greater than the thickness of the through hole, but the inner diameter of the through hole is not less than the outer diameter of the limiting ball.

3. The pressure conduit switching valve for hydraulic testing according to claim 1, characterized in that, When the spring is in the natural elongation state, the jack extends out of the limiting groove. At this time, the limiting ball in the piston lance head is clamped in the lance groove and the through hole to fix the piston lance head in the piston base body. When the piston lance head is pulled, the piston lance head drives the sealing piston to move in the cavity of the valve body until the maximum stroke is reached. At this time, the piston base body blocks the water inlet hole. When the piston lance head is continuously pulled, the jack compresses the spring until the spring is compressed to the shortest. The lance groove, the through hole and the jack groove are aligned. The limiting ball deviates from the lance groove to the jack groove. The limitation of the piston lance head is released and is slidable in the axial through hole. The piston lance head comprises a blocking part, a connecting part and a tapered head part connected in sequence. The blocking part is arranged in the axial through hole of the piston base body. The lance groove is arranged on the outer side wall of the blocking part.

4. The pressure conduit switching valve for hydraulic testing according to claim 3, characterized in that The tapered head part is tapered and gradually decreases in diameter away from the impression device.

5. The pressure conduit switching valve for hydraulic testing according to claim 4, characterized in that The connecting part extends into the drill pipe from the cavity and is connected with the tapered head part. The maximum outer diameter of the tapered head part is greater than the inner diameter of the end of the cavity near the drill pipe.

6. The pressure conduit switching valve for hydraulic testing according to claim 4, characterized in that A plurality of first sealing rings are arranged on the outer wall of the blocking part. The plurality of first sealing rings are arranged below the lance groove on the side wall of the blocking part near the impression device.

7. The pressure conduit switching valve for hydraulic testing according to claim 4, characterized in that ​ 8. The pressure conduit switching valve for hydraulic testing according to claim 1, characterized in that, A plurality of second sealing rings are arranged on the inner wall of the piston base, and the plurality of second sealing rings are respectively arranged on both sides of the water inlet hole.

9. A fracture impression system, comprising: The hydraulic test pressure channel switching valve, the mold device and the electronic compass are arranged at the end of the mold device, wherein the mold device comprises a first mold and a second mold which are connected in series, the first mold comprises a first center tube and a first rubber plug sleeved on the first center tube, a closed first inner cavity is formed between the first rubber plug and the first center tube, the second mold comprises a second center tube and a second rubber plug sleeved on the second center tube, a closed second inner cavity is formed between the second rubber plug and the second center tube, the first center tube and the second center tube are sequentially connected to form a center through hole of the mold device, the first inner cavity is communicated with the water inlet hole, and a plurality of water outlet holes are arranged on the second center tube, and the second inner cavity is communicated with the second center tube through the plurality of water outlet holes.

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