A device for water pressure test of borehole

Abstract

The utility model discloses a kind of drilling water pressure test devices, including water stop plug assembly, the upper end of water stop plug assembly is connected water injection valve, water injection valve includes valve body, valve core, valve body is sequentially centrally arranged from lower end to upper end the through hole of mutual intercommunication and diameter ladder increasing, spring hole, valve core hole, the inner periphery of valve core hole is equipped with bushing, the water injection cavity in capsule is communicated with the water injection passage of water injection valve;The upper end of valve core is connected with rotating rod, the lower end of valve core is inserted into valve core hole and is equipped with spring between the lower end of spring hole, valve core can be moved along valve core hole, the lower end of valve core is communicated with outside by water pressure passage hole, valve core is equipped with the upper blind hole extending from upper end downward, the lower part of upper blind hole is extended to valve core outside by the capsule water injection hole of radially arranged and forms water pressure passage, when spring is not compressed, capsule water injection hole is communicated with water injection passage.The invention avoids reducing the leakage between expansion plug and hole wall, test result is accurate, and cost is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of engineering survey, and specifically relates to a borehole water pressure test device. Background Technology

[0002] Hydropower exploration typically requires various physical and mechanical property tests as well as hydrogeological tests. Among these, the water pressure test (5m as a test section), as described in CN102221712B, is a commonly used in-situ testing method to obtain hydrogeological data. The water pressure test is usually conducted after drilling is completed and the drill rod is fully withdrawn. Then, a water pressure plug and a water injection pipe are lowered into the borehole for the test. The borehole is sealed by two water pressure plugs, and water is then injected into the space between the two plugs through the water injection pipe.

[0003] The drawbacks of traditional water pressure testing are as follows: Conventional borehole water pressure testing requires all drill string to be pulled out of the borehole before lowering an independent expansion plug (or capsule) and a dedicated water injection pipe. After the packer is set, the water pressure pipe is replaced for the test. After the test, the drill string is pulled out again to retrieve the packer. Each test requires at least two drill string pulls, taking 2–3 hours, which is a high percentage of machine shifts and keeps exploration costs high. Due to the increased water pressure in the borehole during pipe replacement, water in the expansion plug may be forced out, causing the packer to loosen or shift, resulting in upper leakage. Test water also tends to seep along the borehole wall, leading to generally higher measured Lü Rong values, which cannot accurately reflect the permeability of the rock mass. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a single-circuit single-plug high-pressure water pressure test device for boreholes, which can use only one pressurization pipeline of the drill rod. A water circuit conversion component is added between the drill rod and the plug. During the test, water is first injected into the plug to pressurize it, and then the water circuit is converted to the test section of the borehole rock mass through the water circuit conversion component for testing. The water circuit conversion component is used to seal the water injection port of the expansion plug to prevent water in the expansion plug from being forced out and to reduce leakage between the expansion plug and the borehole wall.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows: a drilling water pressure test device, comprising a water-stopping plug assembly, which consists of a core tube, a capsule sleeved outside the core tube, and a connector that seals both ends of the capsule to the core tube. The two ends of the capsule are sealed to the connector using a compression cap and a conical sleeve. The upper end of the core tube is connected to a water injection valve, which includes a valve body and a valve core. The valve body extends from the lower end to the upper end, and sequentially features interconnected through holes, spring holes, and valve core holes with progressively increasing diameters. A bushing is fitted inside the valve core hole. A water injection cavity is formed between the core tube and the capsule. A water injection channel extending upwards from the lower end is provided in the shell of the valve body, and the upper side of the water injection channel is connected to a radially arranged valve body through hole. Extending into the valve core hole, the bushing has a bushing hole corresponding to the valve body through hole, and the bushing hole penetrates the inner and outer sides of the bushing. The water injection chamber inside the capsule is connected to the water injection channel of the water injection valve. The upper end of the valve core is connected to the rotating rod, and the lower end of the valve core extends into the valve core hole and is provided with a spring between it and the lower end of the spring hole. The valve core can move along the bushing. The lower end of the valve core is connected to the outside through the pressure water channel hole. The valve core has an upper blind hole extending downward from the upper end. The lower part of the upper blind hole extends to the outside of the valve core through the radially arranged capsule water injection hole to form a pressure water channel. When the valve core presses the spring into the spring hole, the capsule water injection hole on the valve core is not blocked by the bushing. When the spring pushes the valve core to return to its original position, the capsule water injection hole is aligned and connected with the water injection channel.

[0006] The water plug assembly has a water injection pipe inside the connector on the side near the water injection valve. One end of the water injection pipe is connected to the water injection chamber inside the capsule, and the other end is connected to the water injection pipe connector.

[0007] The lower end of the water injection channel is connected to the water injection pipe connector on the water plug assembly connector via the capsule water injection pipe.

[0008] The bushing has annular grooves on its inner and outer circumferences, and O-rings are filled in the annular grooves.

[0009] The lower end of the valve body 5 is provided with a protruding columnar tube, which is pivotally connected to the core tube.

[0010] The pressure water channel hole is radially arranged inside the lower end of the valve core, with one end extending to the lower blind hole (65) and the other end extending to the outer periphery of the valve core.

[0011] Beneficial effects: This utility model can use only one pressurized pipeline on the drill rod and add a water circuit conversion component between the drill rod and the plug for testing, which effectively prevents water from being forced out of the expansion plug, reduces leakage between the expansion plug and the hole wall, makes the data test results accurate, reduces the number of times the drill is pulled up, improves work efficiency, reduces costs, and makes operation more convenient. Attached Figure Description

[0012] Figure 1 Diagram showing the water injection status of the expansion plug in the borehole water pressure test device; Figure 2This is a diagram showing the water injection status of the drill rod in the borehole pressure water test device. Detailed Implementation

[0013] In the description of this utility model, it should be understood that the terms "above", "below", "top", "upper part", "middle part", "bottom", "axial", "radial", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0014] In this utility model, unless otherwise explicitly specified and limited, the terms "connected," "installed," and "equipped with" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0015] like Figure 1-2 As shown, a borehole water pressure testing device includes a water-stopping plug assembly, a water injection valve, and a coupling. The water-stopping plug assembly is prior art disclosed in CN2139953Y. The water-stopping plug assembly consists of a core tube 1, a capsule 2 that is sleeved outside the core tube 1, and a connector 3 that seals both ends of the capsule 2 to the core tube 1. The two ends of the capsule 2 are sealed to the connector 3 using a compression cap 4 and a conical sleeve. The upper end of the core tube 1 is connected to the water injection valve.

[0016] The connector 3 near the water valve of the water plug assembly is equipped with a water injection pipe 31. One end of the water injection pipe 31 is connected to the water injection chamber 33 inside the capsule 2, and the other end is connected to the water injection pipe connector 34.

[0017] The water injection valve includes a valve body 5 and a valve core 6. The lower end of the valve body 5 has a protruding cylindrical tube 51. From the lower end to the upper end of the valve body 5, interconnected through holes 52, a spring hole 53, and a valve core hole 54 with progressively increasing diameters are arranged sequentially. The cylindrical tube 51 is pivotally connected to the core tube 1. A bushing 55 is fitted inside the valve core hole 54, with the length of the bushing 55 being less than the length of the valve core hole 54. A certain distance is spaced between the bottom of the valve core hole 54 and the bottom of the bushing 55. Annular grooves 56 are provided on the inner and outer circumferences of the bushing 55, and O-ring seals 57 are filled in the annular grooves 56. The lower end of the valve core 6 extends into the valve core hole 54 and can move along the valve core hole 54. The upper end of the valve core 6 is connected to a rotating rod above the valve body 5 via a vertically connected coupling 7. The rotating rod is open at both ends for injecting water into the valve core 6.

[0018] The valve core 6 has an upper blind hole 61 extending downward from its upper end. The lower part of the upper blind hole 61 extends to the outside of the valve core 6 through a radially arranged capsule water injection hole 62, serving as a pressure water channel. A spring 8 is provided between the lower end of the valve core 6 and the lower end of the spring hole 53. The lower end of the valve core 6 has a lower blind hole 65 extending upward from its upper end. The lower blind hole 65 also communicates with the pressure water channel hole 66 at the lower end of the valve core 6. The pressure water channel hole 66 is arranged radially inside the lower end of the valve core 6, with one end extending to the lower blind hole 65 and the other end extending to the outer periphery of the valve core 6. The shell of the valve body 5 has an axially extending water injection channel 58. The lower end of the water injection channel 58 is connected to the water injection pipe connector on the water plug assembly connector 3 through a capsule water injection pipe 59. The upper end of the water injection channel 58 is connected to the valve body through hole 71. The valve body through hole 71 is arranged radially inside the valve body 5 and extends to the inner periphery of the valve body 5. The bushing 55 is provided with a bushing hole 551 corresponding to the valve body through hole 71, and the bushing hole 551 passes through the inner and outer sides of the bushing 55.

[0019] When in use, the stop plug assembly of the borehole pressure test device is inside the borehole and the spring 8 of the water injection valve is not compressed. The valve core 6 is in its original position. The capsule water injection hole 62 on the valve core 6, the valve body through hole 71 on the valve body 5, and the bushing hole 551 are aligned and connected to each other. Water can be injected into the water injection channel 58 through the rotating rod, the coupling 7, and the valve core 6. Water flows into the water injection chamber 33 inside the capsule 2 through the capsule water injection pipe 59 and the water injection pipe 31 in the connector 3 of the water plug assembly. This causes the capsule 2 to expand, sealing the upper part of the borehole and isolating the borehole test section from other parts of the borehole wall.

[0020] Then, the valve core 6 is pressed down. When the lower end of the valve core 6 contacts the bottom of the valve core hole 54, the capsule water injection hole 62 on the valve core 6 moves to the position between the bottom of the bushing 55 and the valve core hole 54. Water can be injected into the valve core hole 54 through the rotating rod, coupling 7, and valve core 6. The bushing 55 blocks the water from the valve core hole 54 from flowing into the valve body through hole 71 and bushing hole 551. The water in the valve core hole 54 can only flow into the columnar tube 51 from the pressure water channel hole 66 and the lower blind hole 65 at the lower end of the valve core 6. The water flows into the drilled test section along the core tube 1 to carry out the pressure water test.

[0021] While the specific embodiments of this disclosure have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this disclosure. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this disclosure are still within the scope of protection of this disclosure.

Claims

1. A borehole water pressure test device, comprising a water-stopping plug assembly, the water-stopping plug assembly consisting of a core tube (1), a capsule (2) sleeved outside the core tube (1), and a connector (3) sealing both ends of the capsule (2) to the core tube (1), the two ends of the capsule (2) being sealed to the connector (3) by a compression cap (4) and a conical sleeve, characterized in that, The upper end of the core tube (1) is connected to a water injection valve. The water injection valve includes a valve body (5) and a valve core (6). The valve body (5) extends from the lower end to the upper end and includes a through hole (52), a spring hole (53), and a valve core hole (54) that are centrally located, interconnected, and have progressively increasing diameters. A bushing (55) is fitted inside the valve core hole (54). A water injection cavity (33) is formed between the core tube (1) and the capsule (2). A water injection channel (58) extending upward from the lower end is provided in the shell of the valve body (5). The upper side of the water injection channel (58) extends into the valve core hole (54) through a radially arranged valve body through hole (71). The bushing (55) has a bushing hole (551) corresponding to the valve body through hole (71). The bushing hole (551) penetrates the inner and outer sides of the bushing (55). The water injection cavity (33) inside the capsule (2) is connected to the core tube (54). The water injection channel (58) of the water injection valve is connected; the upper end of the valve core (6) is connected to the rotating rod, and the lower end of the valve core (6) extends into the valve core hole (54) and is provided with a spring (8) between it and the lower end of the spring hole (53). The valve core (6) can move along the bushing (55). The lower end of the valve core (6) is connected to the outside through the water pressure channel hole (66). The valve core (6) is provided with an upper blind hole (61) extending downward from the upper end. The lower part of the upper blind hole (61) extends to the outside of the valve core (6) through the radially arranged capsule water injection hole (62) to form a water pressure channel. When the valve core (6) presses the spring (8) into the spring hole (53), the capsule water injection hole (62) on the valve core (6) is not blocked by the bushing (55). When the spring (8) pushes the valve core (6) to reset upward, the capsule water injection hole (62) is aligned and connected with the water injection channel (58).

2. The borehole water pressure testing device according to claim 1, characterized in that, The water plug assembly has a water injection pipe (31) inside the connector (3) near the water injection valve. One end of the water injection pipe (31) is connected to the water injection chamber (33) inside the capsule (2), and the other end is connected to the water injection pipe connector (34).

3. The borehole water pressure testing device according to claim 2, characterized in that, The lower end of the water injection channel (58) is connected to the water injection pipe connector (34) on the water plug assembly connector (3) via the capsule water injection pipe (59).

4. The borehole water pressure testing device according to claim 1, characterized in that, The bushing (55) has an annular groove (56) on its inner and outer circumferences, and an O-ring (57) is filled in the annular groove (56).

5. The borehole water pressure testing device according to claim 1, characterized in that, The lower end of the valve body (5) is provided with a protruding columnar tube (51), which is pivotally connected to the core tube (1).

6. The borehole water pressure testing device according to claim 1, characterized in that, The water pressure channel hole (66) is radially disposed inside the lower end of the valve core (6), with one end extending to the lower blind hole (65) and the other end extending to the outer periphery of the valve core (6).

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