Drill rod drainage device for hydraulic test

Abstract

The utility model discloses a drill rod drainage device for a hydraulic test, which comprises 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 a hydraulic test device, the valve body is provided with a central through hole along the axial direction of the drill rod, and the valve body is also provided with a drainage hole communicated with the central through hole; when a hydraulic test is carried out, the leakage preventing piston is clamped in the center through hole of the valve body to prevent water in the drill rod from flowing out of the water drainage hole, a center water path with one end communicated with the drill rod and the other end communicated with the hydraulic test device is further arranged on the leakage preventing piston, and the water in the drill rod flows into the hydraulic test device from the center water path during the hydraulic test; and after the hydraulic test is finished, the leakage preventing piston is pulled out, and water in the drill rod flows into the drill hole from the central through hole and the drainage hole. According to the utility model, the purpose of quick drainage and pressure relief after the deep drilling hydraulic test is completed can be achieved, and the difficulty and risk of drill lifting are reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of rock mechanics tests, and particularly relates to a drill rod water drainage device for hydraulic tests. Background Art

[0002] At present, wireline coring drilling technology has been popularized in the drilling construction of deep boreholes. For the convenience of implementation, hydraulic tests in boreholes often need to be carried out with the help of wireline coring drill rods. For example, in-situ stress tests by hydraulic fracturing method, conventional water pressure tests, high-pressure water pressure tests, etc. In deep boreholes, after the hydraulic test is completed, a large amount of water usually remains stored in the drill rod. During the process of pulling out the drill, the drilling rig often needs to bear a greater weight. Even in dry holes, the pressure formed by the water head difference inside and outside the drill rod causes the rubber plug to expand and it is impossible to pull out the drill, which greatly increases the difficulty and risk of pulling out the drill. In order to reduce the pressure on the drilling rig when pulling out the drill and lower the risk of pulling out the drill after the test, it is necessary to drain the water in the drill rod in advance, so as to improve the test efficiency and reduce the test cost. Therefore, it is of great significance to invent a drill rod hole internal water drainage device suitable for hydraulic tests. Content of the Utility Model

[0003] The purpose of the utility model is to provide a drill rod water drainage device for hydraulic tests aiming at the deficiencies of the prior art. This device can achieve the purpose of quickly draining water and relieving pressure after the hydraulic test of deep boreholes, and reduce the difficulty and risk of pulling out the drill.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A drill rod water drainage device for hydraulic tests, comprising:

[0006] A valve body, one end of which is connected to the drill rod, and the other end of the valve body is connected to the hydraulic test device. A central through hole is axially arranged on the valve body along the drill rod, and a water drainage hole communicating with the central through hole is also arranged on the valve body;

[0007] A water blocking piston. During the hydraulic test, the water blocking piston is clamped in the central through hole of the valve body to block the water in the drill rod from flowing out through the water drainage hole. A central water passage with one end connected to the drill rod and the other end connected to the hydraulic test device is also arranged on the water blocking piston. During the hydraulic test, the water in the drill rod flows into the hydraulic test device through the central water passage; after the hydraulic test is completed, the water blocking piston is pulled out, and the water in the drill rod flows from the central through hole and the water drainage hole into the borehole.

[0008] Preferably, the water blocking piston includes a blocking part, a connecting part and a conical head which are connected in sequence, and the blocking part is clamped in the central through hole of the valve body.

[0009] Preferably, a plurality of sealing rings are arranged on the outer wall of the blocking part, and the plurality of sealing rings are respectively located on the side of the water drainage hole away from the hydraulic test device and the side of the water drainage hole close to the hydraulic test device.

[0010] Preferably, a plurality of water inlet holes are provided on the side wall of the blocking portion exposed outside the central through hole, and the plurality of water inlet holes communicate with the central water passage.

[0011] Preferably, it further includes a fishing tool for clamping the blocking piston, and the fishing tool is also connected to a winch through a rope.

[0012] Preferably, the fishing tool includes a first clamping member and a second clamping member that are hinged to each other in the middle. One ends of the first clamping member and the second clamping member away from the valve body are connected by a spring. When the spring is in a natural elongation state, the ends of the first clamping member and the second clamping member close to the valve body form a triangular clamping opening for clamping the conical head of the blocking piston, and the size of the triangular clamping opening in the initial state is smaller than the size of the conical head.

[0013] Preferably, a first auxiliary member is provided on the side wall of the first clamping member away from the second clamping member, and a second auxiliary member is provided on the side wall of the second clamping member away from the first clamping member. The first auxiliary member and the second auxiliary member are arranged facing each other and the lengths of both are greater than those of the first clamping member and the second clamping member.

[0014] Preferably, the length difference between the two auxiliary members and the two clamping members is greater than the sum of the lengths of the connecting portion and the conical head.

[0015] Preferably, the distance between the inner side wall of the first auxiliary member extending out of the first clamping member and the inner side wall of the second auxiliary member extending out of the second clamping member is equivalent to the diameter of the blocking portion.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows: In deep drilling, since there is usually a large amount of water stored in the drill pipe after the hydraulic test, the drilling rig often needs to bear a greater weight during the process of lifting the drill pipe. Even in dry holes, the rubber plug cannot be lifted due to the pressure formed by the water head difference inside and outside the drill pipe. Based on this, the present utility model provides a water discharge device. After the hydraulic test is completed, this device can discharge the water in the drill pipe from the water discharge hole to the drill hole by pulling out the blocking piston, which also plays a role in pressure relief. There is no water head difference between the inside and outside of the drill pipe, and the rubber plug of the test device in the hole will not expand, preventing the risk of sticking the drill pipe and greatly reducing the difficulty and risk of lifting the drill pipe; the absence of water in the drill pipe can reduce the load on the lifting device during the process of lifting the drill pipe and can effectively reduce energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of the water discharge device according to an embodiment of the present utility model;

[0018] Figure 2 is a schematic structural diagram of the valve body according to an embodiment of the present utility model;

[0019] Figure 3Schematic diagram of the structure of the leakage-blocking piston in the embodiment of the present utility model;

[0020] Figure 4 Diagrams of different states in the working process of the embodiment of the present utility model, where (a) is before water discharge, (b) is during water discharge, and (c) is after water discharge. Specific embodiments

[0021] The technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0022] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments may be combined with each other.

[0023] The present invention will be further described below in conjunction with specific embodiments, but it is not a limitation of the present invention.

[0024] The embodiment of the present invention discloses a drill pipe water discharge device for hydraulic tests, as Figure 1 shown, which includes a valve body 11 and a leakage-blocking piston 12 clamped in the valve body 11. See Figure 2 . One end of the valve body 11 is connected to the drill pipe 2, and the other end of the valve body 11 is connected to the hydraulic test device 5. A central through hole 110 is also provided on the valve body 11 along the axial direction of the drill pipe, and a plurality of water discharge holes 111 communicating with the central through hole 110 are provided on the valve body 11 along the radial direction of the drill pipe 2. The water discharge holes 111 communicate with the drill holes outside the drill pipe 2 and are used to discharge the water in the drill pipe 2 at the end of the test.

[0025] See Figure 3, the blocking piston 12 includes a blocking portion 120, a connecting portion 121, and a conical head 122 that are connected in sequence and integrally formed. Among them, the blocking portion 120 is clamped in the central through hole 110 of the valve body 11 during the hydraulic test to block the water in the drill pipe 2 from flowing out through the water discharge hole 111. In order to improve the water blocking effect, a plurality of sealing rings 123 are sleeved on the blocking portion 120, and the plurality of sealing rings 123 are respectively located on one side of the plurality of water discharge holes 111 away from the hydraulic test device 5 and on one side of the water discharge holes 111 close to the hydraulic test device 5. The blocking portion 120 extends out of the central through hole 110, and a plurality of water inlet holes 124 are provided on the side wall of the blocking portion 120 extending out of the central through hole 110, and a central water passage 125 communicating with the plurality of water inlet holes 124 is provided in the axial direction of the blocking portion 120. In this way, during the hydraulic test, the water in the drill pipe 2 flows into the hydraulic test device 5 through the water inlet holes 124 and the central water passage 125. The connecting portion 121 is funnel-shaped, and its diameter near the conical head 122 is smaller than its diameter near the blocking portion 120. The connecting portion 121 and the conical head 122 are both located on the side of the drill pipe 3 away from the hydraulic test device 5.

[0026] To facilitate the extraction of the leakage-blocking piston 12, a fishing tool 4 for clamping the conical end of the leakage-blocking piston is also provided. The fishing tool 4 is also connected to a winch through a rope 6. The fishing tool 4 includes a first clamping member 401 and a second clamping member 402 that are hinged to each other in the middle. One ends of the first clamping member 401 and the second clamping member 402 away from the valve body 11 are connected by a spring 403. When the spring 403 is in a natural elongation state, a triangular clamping opening 404 for clamping the conical head 122 of the leakage-blocking piston 12 is formed at one ends of the first clamping member 401 and the second clamping member 402 close to the valve body, and the size of the triangular clamping opening 404 in the initial state is smaller than the size of the conical head 122. In this way, when the leakage-blocking piston needs to be extracted, the fishing tool 4 is lowered by the winch. Under the action of gravity, the conical head 122 of the leakage-blocking piston 12 is caught in the triangular clamping opening 404 of the fishing tool 4. To improve the clamping effect, a first auxiliary member 405 is provided on the outer side of the first clamping member 401, and a second auxiliary member 406 is provided on the outer side of the second clamping member 402. The first auxiliary member 405 and the second auxiliary member 406 are arranged facing each other and their lengths are both greater than those of the first clamping member 401 and the second clamping member 402. Among them, the length difference between the two auxiliary members and the two clamping members is greater than the sum of the lengths of the connecting portion 121 and the conical head 122. In addition, the distance between the inner side wall of the first auxiliary member 405 extending out of the first clamping member 401 and the inner side wall of the second auxiliary member 406 extending out of the second clamping member 402 is equivalent to the diameter of the blocking portion 120. To facilitate the fixing of the rope, the first auxiliary member 405 and the second auxiliary member 406 can be integrally formed, and the rope is fixed at its top. In this way, when the winch lowers the fishing tool 4, the two auxiliary members of the fishing tool 4 first limit the leakage-blocking piston 12 inside them. As the fishing tool 4 is gradually lowered, the conical head 122 of the leakage-blocking piston 12 is pushed into the triangular clamping opening 404. Under the action of the spring 403, the leakage-blocking piston 12 is firmly clamped. At this time, the winch pulls the rope, and the leakage-blocking piston 12 is extracted from the central through hole by the fishing tool 4.

[0027] The usage method of the water discharge device in this embodiment will be described below. After the hydraulic test is completed, the waterway device at the orifice of the surface drill pipe is removed. At this time, the working state is as Figure 4 (a) shown. From Figure 4As can be seen from (a), at this time, the leakage blocking piston 12 is clamped in the central through hole 110 of the valve body 11. At this time, the water passage 3 in the drill pipe 2 is communicated with the hydraulic test device 5 through the water inlet hole 124 and the central water passage 125. Then, a fishing tool 4 is put into the drill pipe 2 through a rope connected to a winch. When the fishing tool 4 is lowered in the drill pipe 2 and approaches the leakage blocking piston 12, the first auxiliary member 405 and the second auxiliary member 406 first clamp the blocking portion 120. As it is gradually lowered, the conical head 122 of the leakage blocking piston 12 is caught in the triangular clamping opening 404 of the fishing tool 4. The fishing tool 4 is lifted upward by the winch to extract the leakage blocking piston 12 from the valve body 11. At this time, a plurality of water discharge holes 111 are communicated with the water 3 in the drill pipe 2, and the water 3 in the drill pipe 2 flows from the water discharge holes 111 into the drill hole, and the water level in the drill pipe 2 drops rapidly. The working process is as shown in Figure 4 (b) and (c). Finally, the fishing tool 4 and the leakage blocking piston 12 are lifted out. At this time, all the water 3 in the drill pipe has completely drained into the drill hole, and the drill pipe 2 and the hydraulic test device 5 in the drill hole can be easily lifted out by operating the lifting system.

[0028] The above are only the preferred embodiments of the present invention, and do not limit the implementation manners and protection scope of the present invention. For those skilled in the art, it should be able to realize that all the equivalent replacements and obvious changes made by using the content of the specification of the present invention should be included in the protection scope of the present invention.

Claims

1. A drill pipe water discharge device for hydraulic testing, characterized in that: include: A valve body, one end of which is connected to the drill pipe, and the other end of which is connected to the hydraulic test device. A central through hole is arranged on the valve body along the axial direction of the drill pipe, and a drain hole connected to the central through hole is also arranged on the valve body; The anti-leakage piston is stuck in the central through hole of the valve body to block the water in the drill pipe from flowing out from the drain hole when conducting a hydraulic test. A central water channel is also provided on the anti-leakage piston, one end of which is connected to the drill pipe and the other end is connected to the hydraulic test device. During the hydraulic test, the water in the drill pipe flows into the hydraulic test device from the central water channel. After the hydraulic test is completed, the anti-leakage piston is pulled out, and the water in the drill pipe flows into the drill hole from the central through hole and the drain hole.

2. The drill pipe drain device for hydraulic testing according to claim 1, characterized in that: The anti-leakage piston comprises a blocking portion, a connecting portion and a conical head which are connected in sequence, and the blocking portion is clamped in the central through hole of the valve body.

3. The drill pipe drain device for hydraulic testing according to claim 2, characterized in that: A plurality of sealing rings are arranged on the outer wall of the blocking portion, and the plurality of sealing rings are respectively located at a side of the drain hole away from the hydraulic test device and a side of the drain hole close to the hydraulic test device.

4. The drill pipe drain device for hydraulic testing according to claim 2, characterized in that: A plurality of water inlet holes are arranged on the side wall of the blocking portion exposed outside the central through hole, and the plurality of water inlet holes are communicated with the central water channel.

5. The drill pipe drain device for hydraulic testing according to claim 2, characterized in that: The utility model also comprises a fishing device for clamping the leakage-proof piston, and the fishing device is also connected to the winch through a rope.

6. The drill pipe drain device for hydraulic testing according to claim 5, characterized in that: The salvage device includes a first clamping member and a second clamping member hinged to each other in the middle, and the first clamping member and the second clamping member are connected at one end away from the valve body by a spring. When the spring is in a naturally extended state, the first clamping member and the second clamping member form a triangular clamping opening at one end close to the valve body for clamping the conical head of the leakage-proof piston, and the size of the triangular clamping opening in the initial state is smaller than the size of the conical head.

7. The drill pipe drain device for hydraulic testing according to claim 6, characterized in that: A first auxiliary part is arranged on the side wall of the first clamping part away from the second clamping part, and a second auxiliary part is arranged on the side wall of the second clamping part away from the first clamping part. The first auxiliary part and the second auxiliary part are arranged opposite to each other and both are longer than the first clamping part and the second clamping part.

8. The drill pipe drain device for hydraulic testing according to claim 7, characterized in that: The difference in length between the two auxiliary parts and the two clamping parts is greater than the sum of the lengths of the connecting part and the conical head.

9. The drill pipe drain device for hydraulic testing according to claim 7, characterized in that: The distance between the inner side wall of the first auxiliary member extending out of the first clamping member and the inner side wall of the second auxiliary member extending out of the second clamping member is equivalent to the diameter of the blocking portion.

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