Perforating gun body pressure relief blind hole pressure resistance test device

Abstract

The utility model relates to a pressure-resistant test device, in particular to a pressure-resistant test device for a pressure relief blind hole of a perforating gun body, which solves the problems that the existing pressure-resistant test device is large in occupied area demand and low in test efficiency, and high-pressure gas always exists in a large-sized high-pressure kettle, so that certain potential safety hazards exist. The high-pressure joint is screwed in the threaded hole of the fixed pipe, the inner end of the high-pressure joint extends into the fixed pipe, and the outer end of the high-pressure joint is connected with a high-pressure pipeline; the inner end of the high-pressure connector is connected with a pressure relief blind hole of a test piece arranged in the fixed pipe, and the test piece is formed by cutting a pipe fitting used for manufacturing the perforating gun into N sections; each section serves as a test piece, a plurality of pressure relief blind holes are formed in the outer wall of the test piece, abutting planes are arranged at the positions, corresponding to the pressure relief blind holes, of the outer wall of the test piece, and the inner end of the high-pressure connector is connected with one of the pressure relief blind holes; the end face of the inner end of the high-pressure connector abuts against the abutting plane, and a center hole of the high-pressure connector corresponds to the pressure relief blind hole.

Description

Technical Field

[0001] The utility model relates to a pressure resistance test device, in particular to a pressure resistance test device for a perforating gun body pressure relief blind hole. Background Art

[0002] In oil and gas field exploitation operations, composite perforation technology can reduce the initiation pressure, increase the critical pressure difference for sand production, and improve the flow efficiency of the fluid. Composite perforation technology also plays an important role in promoting the formation of fracture networks and expanding the drainage area of ​​oil reservoirs in volume fracturing, so it has been gradually promoted and used.

[0003] One of the most important components in composite perforating technology is the perforating gun. Commonly used perforating guns generally store perforating bullets and composite explosives inside a tubular gun body, and a number of pressure relief blind holes are arranged on the outer wall of the gun body. When the perforating gun is lowered into the well and reaches the specified depth, the depth is calibrated and then its position is adjusted to face the predetermined perforating direction. After the adjustment is completed, the perforating bullets and composite explosives are detonated. Because the structure at the pressure relief blind hole is weaker than that of other parts of the gun body, the perforating bullets and composite explosives will break through the pressure relief blind hole after the explosion, thus achieving composite perforation of the formation at that depth.

[0004] Because the perforating gun body needs to detonate the perforating bullets and composite explosives, its strength must ensure that the perforating bullets and composite explosives can only be ejected from the pressure relief blind hole during detonation without causing damage to other parts, and the deformation of the perforating gun body cannot exceed the standard requirements. Therefore, when designing the perforating gun, the selected materials need to undergo a pressure resistance test. The pressure resistance test is to apply pressure to the pressure relief blind hole and collect the pressure values ​​when different pressure relief blind holes are penetrated by high pressure. The test results obtained can provide data support for the selection of materials for the perforating gun.

[0005] The existing pressure test device usually takes the entire perforating gun as the test object, and the perforating gun is generally very long. In order to fix the perforating gun, the entire test device requires a large area. Secondly, when clamping the perforating gun, the existing pressure test device requires the cooperation of several people to complete the clamping, which leads to a longer test time and lower test efficiency. Thirdly, the pressure test conducted by the existing pressure test device is generally carried out in a large autoclave, and the procurement cost of the large autoclave is relatively high. During the test, high-pressure gas is always stored inside the large autoclave, which poses certain safety hazards. Utility Model Content

[0006] The utility model aims to solve the technical problems that the existing pressure test device has large floor space requirements, low test efficiency, and high-pressure gas always exists in the large autoclave, which has certain safety hazards, and provides a perforating gun body pressure relief blind hole pressure test device.

[0007] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0008] A perforating gun body pressure relief blind hole pressure resistance test device, which is special in that it includes a test assembly and a test piece;

[0009] The test assembly includes a fixed pipe and a high-pressure joint;

[0010] The fixed tube is provided with a threaded hole in the radial direction, the high-pressure joint is screwed into the threaded hole, and the inner end of the high-pressure joint extends into the fixed tube, and the outer end is used to connect with the high-pressure pipeline;

[0011] The test piece is formed by cutting a pipe used for making a perforating gun into N sections; each section is used as a test piece, and the outer wall of each test piece has a plurality of pressure relief blind holes, and the outer wall of each test piece is provided with an abutment plane at a position corresponding to the pressure relief blind holes, and the plurality of pressure relief blind holes are arranged along the axial direction; the test piece is set in a fixed pipe;

[0012] A center hole is axially opened on the high-pressure joint, and the inner end of the high-pressure joint is connected to one of the multiple pressure relief blind holes; the inner end face of the high-pressure joint abuts on the abutment plane to achieve sealing between the high-pressure joint and the pressure relief blind hole, and the center hole of the high-pressure joint corresponds to the pressure relief blind hole.

[0013] Furthermore, the distances from the bottom of the multiple pressure relief blind holes to the inner wall of the test piece are different; or, the multiple pressure relief blind holes are divided into multiple groups, each group includes at least two pressure relief blind holes, the distances from the bottom of the pressure relief blind holes in each group to the inner wall of the test piece are the same, and the distances from the bottom of the pressure relief blind holes to the inner wall of the test piece between each group are different.

[0014] Furthermore, corresponding positioning pin holes are opened in the radial direction on the fixed tube and the test piece. There is one positioning pin hole on the fixed tube, which is arranged radially relative to the threaded hole on the fixed tube; there are multiple positioning pin holes on the test piece distributed along the axial direction, and each positioning pin hole is arranged radially relative to the position of each pressure relief blind hole; the test assembly also includes a positioning pin, which is inserted into the positioning pin hole on the fixed tube and one of the positioning pin holes on the test piece.

[0015] Furthermore, a mounting groove is provided on the inner end surface of the high-pressure joint, the center hole is located at the center of the mounting groove, a sealing ring is provided in the mounting groove, the top of the sealing ring abuts against the bottom of the mounting groove, and the bottom abuts against the abutting plane.

[0016] Furthermore, the high-pressure joint includes a small-diameter section arranged near the outer end, a large-diameter section arranged near the inner end, and a connecting section connecting the two, the large-diameter section is screwed into the threaded hole on the fixed pipe, the mounting groove is located on the outer end surface of the large-diameter section, and the outer end surface of the large-diameter section abuts on the abutment plane; the small-diameter section is used to connect to the high-pressure pipeline, and the projection of the outer wall of the connecting section in the vertical direction is a regular hexagon.

[0017] Furthermore, the abutment plane is opened along the axial direction of the test piece, and the plurality of pressure relief blind holes are distributed at the middle position of the abutment plane along the axial direction.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] (1) A pressure resistance test device for a pressure relief blind hole of a perforating gun body provided by the present invention comprises a test assembly and a test piece, wherein the test assembly comprises a fixed pipe and a high-pressure joint installed on the fixed pipe, the outer end of the high-pressure joint is connected to the high-pressure pipeline, and the inner end is used to connect to one of a plurality of pressure relief blind holes on the test piece arranged in the fixed pipe, and the inner end face of the high-pressure joint abuts on the abutting plane where the pressure relief blind hole is located, so as to achieve sealing between the high-pressure joint and the pressure relief blind hole. The test piece is formed by cutting a pipe used for making a perforating gun into N sections, and its length is greatly reduced compared with the entire perforating gun, but its material properties are exactly the same as those of the perforating gun, the area required for the test is reduced, and the weight of the test piece is reduced compared with the previous one, and only one person is required to complete the clamping, thereby improving efficiency; during the entire test process, there is only a high-pressure area between the inner end of the high-pressure joint and the pressure relief blind hole, and the volume of the high-pressure area is significantly reduced. Even if an accident occurs and the two ends of the fixed pipe are not closed, the pressure can be released from the two ends of the fixed pipe, and no explosion will occur, thereby ensuring safety.

[0020] (2) The present invention provides a perforating gun body pressure relief blind hole pressure resistance test device, which has corresponding positioning pin holes on the fixed tube and the test piece in the radial direction. There is one positioning pin hole on the fixed tube, which is arranged radially relative to the threaded hole on the fixed tube; there are multiple positioning pin holes on the test piece distributed along the axial direction, and each positioning pin hole is arranged radially relative to the position of each pressure relief blind hole; the test assembly also includes a positioning pin, which is inserted into the positioning pin hole on the fixed tube and one of the positioning pin holes on the test piece. In this way, depending on which pressure relief blind hole needs to be tested, the positioning pin hole corresponding to the pressure relief blind hole is aligned with the positioning pin hole on the fixed tube, and then the positioning pin is inserted. In this way, after the inner end face of the high-pressure joint abuts against the abutment plane, the center hole of the high-pressure joint will be connected to the pressure relief blind hole, thereby improving the test efficiency.

[0021] (3) A perforating gun body pressure relief blind hole pressure resistance test device provided by the present invention has an installation groove on the inner end face of the high-pressure joint, and a sealing ring is arranged in the installation groove. The top of the sealing ring abuts against the bottom of the installation groove, and the bottom abuts against the abutting plane, which can improve the sealing performance during the test and prevent pressure leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of an embodiment of a perforating gun body pressure relief blind hole pressure resistance test device in use;

[0023] Figure 2 It is a cross-sectional view of a fixed pipe in an embodiment of a perforating gun body pressure relief blind hole pressure resistance test device of the utility model;

[0024] Figure 3 It is a cross-sectional view of a high-pressure joint in an embodiment of a perforating gun body pressure relief blind hole pressure resistance test device of the utility model;

[0025] Figure 4 It is a cross-sectional view of a test piece in an embodiment of a perforating gun body pressure relief blind hole pressure resistance test device of the utility model;

[0026] Figure 5 The utility model is a distribution diagram of the pressure relief blind holes in a perforating gun body pressure relief blind hole pressure resistance test device embodiment.

[0027] The following are the descriptions of the reference numerals:

[0028] 1-fixed pipe, 2-high pressure joint, 21-large diameter section, 22-connecting section, 23-small diameter section, 24-installation groove; 3-locating pin, 4-test piece, 41-pressure relief blind hole, 411-first pressure relief blind hole, 412-second pressure relief blind hole, 413-third pressure relief blind hole, 414-fourth pressure relief blind hole, 42-abutment plane, 5-sealing ring. DETAILED DESCRIPTION

[0029] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments.

[0030] Reference Figure 1-Figure 5 The utility model provides a perforating gun body pressure relief blind hole pressure resistance test device comprising a test assembly and a test piece 4, wherein the test assembly comprises a fixed pipe 1 and a high pressure joint 2 installed on the fixed pipe 1, and the structure of the fixed pipe 1 is as follows Figure 2 As shown, it is a tubular structure with openings at both ends. A threaded hole is radially opened on the fixing tube 1, and a positioning pin hole is also radially opened on the fixing tube 1. The positioning pin hole is arranged radially relative to the threaded hole.

[0031] The structure of the high pressure connector 2 is as follows Figure 3As shown, it includes a large diameter section 21, a small diameter section 23 and a connecting section 22 connecting the two. A center hole is opened axially on the high-pressure connector 2, wherein the large diameter section 21 of the high-pressure connector 2 is arranged near the inner end of the high-pressure connector 2, and the small diameter section 23 is arranged near the outer end of the high-pressure connector 2. The small diameter section 23 is used to connect with the high-pressure pipeline, and the large diameter section 21 is screwed into the threaded hole on the fixed pipe 1, and the large diameter section 21 extends into the fixed pipe 1. The projection of the outer wall of the connecting section 22 in the vertical direction is a regular hexagon. When the high-pressure connector 2 is screwed into the threaded hole, a wrench can be used to cooperate with the connecting section 22 to tighten it.

[0032] A test piece 4 is arranged in the fixed pipe 1. The test piece 4 is obtained by cutting the pipe used to make the perforating gun into N sections, N ≥ 2, each section is a test piece 4, and the outer wall of each test piece 4 has a plurality of pressure relief blind holes 41. The material properties of the test piece 4 obtained in this way are exactly the same as those of the perforating gun, but the length and weight are significantly reduced, the required test area is greatly reduced, and the clamping of the test piece 4 can be completed by a single person, thereby improving the test efficiency. The structure of one of the test pieces 4 is as follows: Figure 4 As shown, an abutment plane 42 is processed along the axial direction on the outer wall of the test piece 4, and a plurality of pressure relief blind holes 41 are distributed in the middle position along the axial direction on the abutment plane 42, and the distance from the bottom of each pressure relief blind hole 41 to the inner wall of the test piece 4 is different. In the present embodiment, four pressure relief blind holes 41 are provided on one of the test pieces 4, namely, a first pressure relief blind hole 411, a second pressure relief blind hole 412, a third pressure relief blind hole 413 and a fourth pressure relief blind hole 414. The four pressure relief blind holes 41 are evenly distributed along the axial direction, and the hole depths of the first pressure relief blind hole 411 to the fourth pressure relief blind hole 414 are arranged in equidistant order from front to back. The first pressure relief blind hole 411 is located at the front end and has the smallest hole depth. In the present embodiment, the hole depth of the first pressure relief blind hole 411 is 1.2 mm, and the second pressure relief blind hole 412 is 1.2 mm. The hole depth of pressure relief blind hole 12 is 1.3mm, the hole depth of the third pressure relief blind hole 413 is 1.4mm, the hole depth of the fourth pressure relief blind hole 414 is 1.5mm, and the depth difference between two adjacent pressure relief blind holes 41 is 0.1mm. In this way, the distance from the bottom of the hole to the inner wall of the test piece 4 of the first pressure relief blind hole 411 is the largest, and the distance from the bottom of the hole to the inner wall of the test piece 4 of the fourth pressure relief blind hole 414 is the smallest. After marking the first pressure relief blind hole 41 located at the front end, the distances of the remaining pressure relief blind holes 41 from the bottom of the hole to the inner wall of the test piece 4 can be calculated by the test personnel themselves, which is convenient for testing.

[0033] Or in other embodiments, for data accuracy, multiple pressure relief blind holes 41 on the same test piece 4 are divided into multiple groups, each group includes at least two pressure relief blind holes 41, and the distances from the bottom of the pressure relief blind holes 41 in each group to the inner wall of the test piece 4 are the same, but the distances from the bottom of the pressure relief blind holes 41 to the inner wall of the test piece 4 are different between groups. In this way, the average value between the same group can be calculated to improve data accuracy.

[0034] During the test, in order to improve the test efficiency, the large diameter section 21 needs to be inserted into the fixed tube 1 and directly aligned with the corresponding pressure relief blind hole 41, so a positioning pin hole is radially opened on the test piece 4, and there are multiple positioning pin holes on the test piece 4 distributed along the axial direction, and each positioning pin hole is arranged radially relative to the position of each pressure relief blind hole 41. In this embodiment, there are four positioning pin holes on the test piece 4. When it is necessary to perform a pressure resistance test on one of the pressure relief blind holes 41, the positioning pin hole corresponding to the pressure relief blind hole 41 is aligned with the positioning pin hole on the fixed tube 1, and then the positioning pin 3 is inserted into the positioning pin hole to fix the position of the pressure relief blind hole 41. In this way, when the outer end face of the large diameter section 21 abuts against the abutting plane 42, the center hole of the high-pressure connector 2 is connected to the pressure relief blind hole 41, so as to achieve the sealing between the pressure relief blind hole 41 and the high-pressure connector 2.

[0035] During the test, the high-pressure area is located between the inner end face of the high-pressure connector 2, that is, the outer end face of the large-diameter section 21 and the pressure relief blind hole 41. The pressure in this part is very high during the test. In order to ensure that there is no pressure leakage, a mounting groove 24 is opened on the outer end face of the large-diameter section 21 of the high-pressure connector 2. The center hole of the high-pressure connector 2 is located at the center position of the mounting groove 24. A sealing ring 5 is arranged in the mounting groove 24. The top of the sealing ring 5 abuts against the bottom of the mounting groove 24, and the bottom abuts against the abutting plane 42. Compared with directly achieving sealing through the outer end face of the large-diameter section 21 and the abutting plane 42, the sealing performance is better.

[0036] When in use, the following steps are specifically included:

[0037] S1: Cut a pipe used for making a perforating gun into N sections, each section being a test piece 4; and machining abutment planes 42 on the outer wall of each test piece 4 corresponding to a plurality of pressure relief blind holes 41; wherein N≥2;

[0038] S2: Screw the high-pressure connector 2 into the threaded hole on the fixed pipe 1, so that the inner end of the high-pressure connector 2 extends into the fixed pipe 1, and then connect the outer end of the high-pressure connector 2 to the high-pressure pipeline;

[0039] S3: Place the test piece 4 into the fixed tube 1, select the locating pin hole on the test piece 4 that is opposite to one of the pressure relief blind holes 41, and align the locating pin hole on the test piece 4 with the locating pin hole on the fixed tube 1, insert the locating pin 3 into the locating pin holes of the test piece 4 and the fixed tube 1, make the inner end surface of the high-pressure joint 2 abut against the abutting plane 42 corresponding to the pressure relief blind hole 41, and make the center hole of the high-pressure joint 2 abut against the pressure relief blind hole 41;

[0040] S4: gradually pressurizing the high-pressure pipeline, recording the pressure value of the pressure instrument set on the high-pressure pipeline when the pressure relief blind hole 41 is ruptured, and completing the pressure resistance test of the pressure relief blind hole 41;

[0041] S5: Return to step S3, and replace the next pressure relief blind hole 41 for the pressure test, until the pressure test of all the pressure relief blind holes 41 on the test piece 4 is completed;

[0042] S6: Replace another test piece 4 and repeat steps S3-S5 until the pressure test of all the pressure relief blind holes 41 on the N test pieces 4 is completed, that is, the pressure test of the pressure relief blind holes 41 of the entire perforating gun body is completed.

[0043] The embodiments described above are merely descriptions of the specific implementation methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A pressure-resistant test device for a perforating gun body pressure relief blind hole, characterized in that: comprising a test assembly and a test piece (4); The test assembly comprises a fixed pipe (1) and a high-pressure joint (2); The fixed tube (1) is provided with a threaded hole in the radial direction, the high-pressure connector (2) is screwed into the threaded hole, and the inner end of the high-pressure connector (2) extends into the fixed tube (1), and the outer end is used to be connected to the high-pressure pipeline; The test piece (4) is formed by cutting a pipe used for making a perforating gun into N sections; each section is a test piece (4); the outer wall of each test piece (4) has a plurality of pressure relief blind holes (41); the outer wall of each test piece (4) is provided with abutment planes (42) at positions corresponding to the pressure relief blind holes (41); the plurality of pressure relief blind holes (41) are arranged axially; the test piece (4) is arranged in a fixed pipe (1); The high-pressure connector (2) is provided with a center hole in the axial direction, and the inner end of the high-pressure connector (2) is connected to one of the plurality of pressure-relief blind holes (41); the inner end surface of the high-pressure connector (2) abuts against the abutment plane (42), thereby achieving sealing between the high-pressure connector (2) and the pressure-relief blind hole (41), and the center hole of the high-pressure connector (2) is arranged corresponding to the pressure-relief blind hole (41).

2. The perforating gun body pressure relief blind hole pressure resistance test device according to claim 1, characterized in that: The distances from the bottom of the plurality of pressure relief blind holes (41) to the inner wall of the test piece (4) are all different; or, the plurality of pressure relief blind holes (41) are divided into a plurality of groups, each group includes at least two pressure relief blind holes (41), the distances from the bottom of the pressure relief blind holes (41) in each group to the inner wall of the test piece (4) are the same, and the distances from the bottom of the pressure relief blind holes (41) to the inner wall of the test piece (4) between the groups are different.

3. The perforating gun body pressure relief blind hole pressure resistance test device according to claim 1 or 2, characterized in that: Positioning pin holes are correspondingly opened in the radial direction on the fixed tube (1) and the test piece (4); there is one positioning pin hole on the fixed tube (1), which is arranged radially relative to the threaded hole on the fixed tube (1); there are a plurality of positioning pin holes on the test piece (4) distributed along the axial direction, and each positioning pin hole is arranged radially relative to the position of each pressure relief blind hole (41); the test assembly also includes a positioning pin (3), which is inserted into the positioning pin hole on the fixed tube (1) and one of the positioning pin holes on the test piece (4).

4. The perforating gun body pressure relief blind hole pressure resistance test device according to claim 3, characterized in that: A mounting groove (24) is provided on the inner end surface of the high-pressure joint (2), the center hole is located at the center of the mounting groove (24), a sealing ring (5) is provided in the mounting groove (24), the top of the sealing ring (5) abuts against the bottom of the mounting groove (24), and the bottom abuts against the abutting plane (42).

5. The perforating gun body pressure relief blind hole pressure resistance test device according to claim 4, characterized in that: The high-pressure joint (2) comprises a small-diameter section (23) arranged near the outer end, a large-diameter section (21) arranged near the inner end, and a connecting section (22) connecting the two. The large-diameter section (21) is screwed into a threaded hole on the fixed pipe (1). The mounting groove (24) is located on the outer end surface of the large-diameter section (21). The outer end surface of the large-diameter section (21) abuts against the abutting plane (42). The small-diameter section (23) is used to connect to the high-pressure pipeline. The projection of the outer wall of the connecting section (22) in the vertical direction is a regular hexagon.

6. The perforating gun body pressure relief blind hole pressure resistance test device according to claim 1, characterized in that: The abutment plane (42) is opened along the axial direction of the test piece (4), and the plurality of pressure relief blind holes (41) are distributed at the middle position of the abutment plane (42) along the axial direction.

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