A gripper for a nuclear magnetic resonance system

Abstract

A holder for a nuclear magnetic resonance system provided by the present invention belongs to the technical field of nuclear magnetic resonance detection, and includes: a clamping main body made of a non-metallic material and having an accommodation cavity for placing a sample; an annular skeleton sleeved on the outer wall of the clamping main body and having a gap with the outer wall of the clamping main body; and a radio frequency coil disposed around the outer wall of the annular skeleton. The clamping main body of the present invention is made of a non-metallic material to avoid the interference of paramagnetic substances on nuclear magnetic resonance signals; the annular skeleton is sleeved on the outer wall of the clamping main body, and the radio frequency coil is wound around the outer wall of the annular skeleton, so that the radio frequency coil does not need to bear the pressure inside the clamping main body; there is a gap between the annular skeleton and the outer wall of the clamping main body, which reduces the heat transfer from the clamping main body to the radio frequency coil; in the above structure, since the radio frequency coil does not need to bear pressure and high heat, a radio frequency coil made of a general material can meet the use requirements and the design cost is relatively low.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear magnetic resonance detection, and particularly relates to a gripper for a nuclear magnetic resonance system. Background Art

[0002] In oil and gas exploration and development as well as deep rock mass engineering, there are complex relationships of interaction and mutual restriction among the stress field, temperature field, seepage field and rock mass deformation field in the environment where the rock mass of the relevant formation is located. During the process of rock mass excavation and oil and gas production, in order to avoid disasters induced by stress concentration and unloading of the rock mass and to avoid affecting the production efficiency due to high temperature, high pressure and high seepage, it is necessary to take out rock samples from the relevant formation and simulate the environment where the rock is located to measure parameters such as porosity, permeability and saturation of the rock samples.

[0003] Most nuclear magnetic resonance grippers adopt an all-metal gripper structure. The nuclear magnetic resonance radio frequency coil can only be placed inside the gripper, and the radio frequency coil also needs to be designed into a pressure-resistant structure. At the same time, the temperature resistance ability of the radio frequency coil also needs to be considered. The design is difficult and the cost is high. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the nuclear magnetic resonance radio frequency coil placed inside the gripper in the prior art is difficult to meet the performance requirements of high pressure and high temperature resistance, so as to provide a gripper for a nuclear magnetic resonance system.

[0005] To solve the above technical problem, the gripper for a nuclear magnetic resonance system provided in the present invention includes:

[0006] A clamping main body, made of a non-metallic material, having a receiving cavity for placing a sample;

[0007] An annular skeleton, sleeved on the outer wall of the clamping main body, and having a gap with the outer wall of the clamping main body;

[0008] A radio frequency coil, arranged around the outer wall of the annular skeleton.

[0009] As a preferred solution, the outer wall of the annular skeleton has a positioning groove suitable for receiving the radio frequency coil.

[0010] As a preferred solution, it further includes: an axial force-bearing body, sleeved on the outer walls of the clamping main body and the annular skeleton.

[0011] As a preferred solution, sealing rings are respectively arranged at both ends of the annular skeleton, and the sealing rings are inserted between the annular skeleton and the outer wall of the clamping main body.

[0012] As a preferred solution, the sealing ring has an abutting platform for abutting against the end of the annular skeleton, and the axial force-bearing body forms an abutment against the sealing ring.

[0013] As a preferred solution, the sealing ring is provided with a coolant receiving groove and a coolant injection hole.

[0014] As a preferred solution, the coolant receiving groove on the sealing ring communicates with the space between the annular skeleton and the clamping body.

[0015] As a preferred solution, at least one through groove is provided on the outer wall of the axially stressed body.

[0016] As a preferred solution, it further includes:

[0017] A shielding cover detachably covers the outside of the RF coil.

[0018] As a preferred solution, an electrical connecting member adapted to be connected to the RF coil is provided on the shielding cover.

[0019] The technical solution of the present invention has the following advantages:

[0020] 1. For the holder for a nuclear magnetic resonance system provided by the present invention, the clamping body is made of a non-metallic material to avoid the interference of paramagnetic substances on the nuclear magnetic resonance signal; the annular skeleton is sleeved on the outer wall of the clamping body, and the RF coil is wound around the outer wall of the annular skeleton, and the RF coil avoids bearing the pressure inside the clamping body; there is a space between the annular skeleton and the outer wall of the clamping body, which reduces the heat transfer from the clamping body to the RF coil. With the above structure, since the RF coil does not need to bear pressure and high heat, an RF coil of a general material can meet the use requirements and the design cost is relatively low.

[0021] 2. For the holder for a nuclear magnetic resonance system provided by the present invention, the positioning grooves on the annular skeleton realize the fixation and positioning of the RF coil.

[0022] 3. For the holder for a nuclear magnetic resonance system provided by the present invention, the setting of the axially stressed body not only increases the strength of the overall structure, but also facilitates the connection and fixation of the annular skeleton.

[0023] 4. For the holder for a nuclear magnetic resonance system provided by the present invention, the sealing ring is inserted between the outer walls of the annular skeleton and the clamping body, ensuring a fixed interval between the annular skeleton and the clamping body.

[0024] 5. For the holder for a nuclear magnetic resonance system provided by the present invention, the sealing ring abuts against the axially stressed body and the annular skeleton respectively, thereby realizing the axial limit of the sealing ring and the annular skeleton.

[0025] 6. For the holder for a nuclear magnetic resonance system provided by the present invention, the heat on the outer wall of the clamping body is conducted to the annular skeleton through the sealing ring, and the coolant cools the sealing ring through the coolant injection hole, thereby reducing the heat conduction phenomenon.

[0026] 7. The holder for the nuclear magnetic resonance system provided by the present invention allows the coolant to flow into the space between the annular skeleton and the clamping body through the coolant receiving groove, cooling and reducing the temperature of the clamping body, and reducing the radiant heat to the annular skeleton.

[0027] 8. The holder for the nuclear magnetic resonance system provided by the present invention has a through groove on the outer wall of the axially stressed body, which facilitates the installation and adjustment of the annular skeleton through the through groove.

[0028] 9. The holder for the nuclear magnetic resonance system provided by the present invention is provided with a shielding cover to prevent the radio frequency coil from radiating to the outside.

[0029] 10. For the holder for the nuclear magnetic resonance system provided by the present invention, the electrical connector connected to the radio frequency coil is arranged inside the shielding cover, that is, the wire connected to the radio frequency coil is also enclosed in the shielding cover to prevent the wire from being pulled out when it is placed outside. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 It is a schematic perspective view of the holder for the nuclear magnetic resonance system provided in the present invention.

[0032] Figure 2 It is Figure 1 the front view cross-sectional view of

[0033] Figure 3 It is a schematic perspective view of the clamping body.

[0034] Figure 4 It is a schematic perspective view of the axial pressure end cover.

[0035] Figure 5 It is Figure 4 the front view cross-sectional view of

[0036] Figure 6 It is a schematic perspective view of the axial pressure push rod.

[0037] Figure 7 It is Figure 6 the front view cross-sectional view of

[0038] Figure 8 It is a schematic perspective view of the axial pressure ejector rod.

[0039] Figure 9is Figure 8 the front view cross-sectional view of

[0040] Figure 10 the front view cross-sectional view of the positioning post.

[0041] Figure 11 is the three-dimensional structure schematic diagram of the axial force-bearing body.

[0042] Figure 12 is Figure 11 the front view cross-sectional view of

[0043] Figure 13 the three-dimensional structure schematic diagram of the axial gland.

[0044] Figure 14 is Figure 13 the front view cross-sectional view of

[0045] Figure 15 the three-dimensional structure schematic diagram of the annular skeleton.

[0046] Figure 16 is the three-dimensional structure schematic diagram of the sealing ring.

[0047] Figure 17 is Figure 16 the front view cross-sectional view of

[0048] Explanation of reference numerals:

[0049] 1. Clamping main body; 2. Axial force-bearing body; 3. Annular skeleton; 4. Axial pressure push rod; 5. Axial pressure ejector rod; 6. Axial pressure end cover; 7. Axial gland; 8. Accommodating cavity; 9. Flat section; 10. First resisting flange; 11. First stepped hole; 12. Second stepped hole; 13. Axial pressure through hole; 14. Surrounding pressure through hole; 15. Driving flange; 16. Sealing gasket ring; 17. First displacement through hole; 18. Second displacement through hole; 19. Second resisting flange; 20. First through hole; 21. Second through hole; 22. Circular groove; 23. Radiation groove; 24. Positioning post; 25. Transition through hole; 26. Third stepped hole; 27. Fourth stepped hole; 28. Through groove; 29. Sleeve; 30. Clamping flange; 31. Stepped groove; 32. Stepped platform; 33. Weight reduction hole; 34. Sealing ring; 35. Positioning groove; 36. Electrical connection component; 37. Housing bracket; 38. End plate; 39. Side wall plate; 40. Abutting platform; 41. Coolant accommodating groove; 42. Coolant injection hole; 43. Groove. Detailed implementation manners

[0050] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0051] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0052] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0053] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0054] The holder for a nuclear magnetic resonance system provided in this embodiment, as Figure 1 、 Figure 2 shown, includes: a clamping main body 1, a plugging component, an axially stressed body 2, an annular skeleton 3, a radio frequency coil, and a shielding cover. The radio frequency coil is sleeved on the outer wall of the clamping main body 1 through the annular skeleton 3. Among them, the plugging component includes: an axial pressure push rod 4, an axial pressure top rod 5, an axial pressure end cover 6, and an axial pressure cover 7.

[0055] As Figure 2 、 Figure 3 shown, the clamping main body 1 is made of zirconia. The clamping main body 1 is a columnar structure and has an accommodation cavity 8 that penetrates axially inside. A sample is suitable to be placed in the accommodation cavity 8. Flat cut surfaces 9 are symmetrically provided on the outer walls at both ends of the clamping main body 1.

[0056] As Figure 2 、 Figure 4 、 Figure 5As shown, the outer wall of the axial compression end cover 6 has a first resisting flange 10 extending radially outward, and internally has a first stepped hole 11 and a second stepped hole 12 penetrating axially; one end of the axial compression end cover 6 extends into the accommodation cavity 8, the first resisting flange 10 abuts against the end of the accommodation cavity 8, and the outer wall of the axial compression end cover 6 is sealingly connected to the inner wall of the accommodation cavity 8 through a sealing ring; one end of the axial compression cover 7 facing the first resisting flange 10 has an axial compression through hole 13 and a confining pressure through hole 14, and both the axial compression through hole 13 and the confining pressure through hole 14 are parallel to the axis of the axial compression cover 7; the axial compression through hole 13 communicates the outside with the second stepped hole 12; the confining pressure through hole 14 communicates the outside with the accommodation cavity 8 of the clamping body 1 and is not communicated with the first stepped hole 11 and the second stepped hole 12.

[0057] As Figure 2 , Figure 6 , Figure 7 shown, the axial compression push rod 4 slides through the first stepped hole 11 and the second stepped hole 12 and partially extends into the accommodation cavity 8; the axial compression push rod 4 has a driving flange 15 extending radially outward, and the outer wall of the driving flange 15 is in contact and sliding connection with the second stepped hole 12; a driving groove is formed between the driving flange 15 and the inner stepped surface of the axial compression end cover 6, and the axial compression through hole 13 communicates with the driving groove; a sealing gasket ring 16 is provided between the driving flange 15 and the inner stepped surface of the axial compression end cover 6, and the sealing gasket ring 16 is in sliding seal with the second stepped hole 12; the outer wall of the driving flange 15 and the second stepped hole 12 are in sliding seal through a sealing ring, and the outer wall of the axial compression push rod 4 and the first stepped hole 11 are in sliding seal through a sealing ring. The interior of the axial compression push rod 4 is provided with a first displacement through hole 17 and a second displacement through hole 18 at intervals, and the first displacement through hole 17 penetrates the axis of the axial compression push rod 4.

[0058] As Figure 2 , Figure 8 , Figure 9 , one end of the axial compression push rod 4 facing the interior of the clamping body 1 is threadedly connected with the axial compression ejector rod 5, and the axial compression ejector rod 5 is made of zirconia material; the axial compression ejector rod 5 has a second resisting flange 19 extending radially outward, and the second resisting flange 19 abuts against the end of the axial compression push rod 4; there is a gap between the outer wall of the second resisting flange 19 and the inner wall of the accommodation cavity 8 of the clamping body 1, and the confining pressure through hole 14 communicates with the accommodation cavity 8 through the gap. The interior of the axial compression ejector rod 5 has a first through hole 20 and a second through hole 21 respectively communicating the first displacement through hole 17 and the second displacement through hole 18, and the end face of the axial compression ejector rod 5 has a circular groove 22, and the circular groove 22 is communicated with the first through hole 20 and the second through hole 21 through a radial groove 23.

[0059] As Figure 2 , Figure 10 shown, a positioning post 24 is connected between the first displacement through-hole 17 and the first through-hole 20. One end of the positioning post 24 is embedded in the first through-hole 20, and the other end is embedded in the first displacement through-hole 17. A transition through-hole 25 communicating the first displacement through-hole 17 and the first through-hole 20 is provided inside the positioning post 24. The outer wall of the positioning post 24 is hermetically connected to the first displacement through-hole 17 and the first through-hole 20 respectively through a sealing ring.

[0060] As Figure 2 , Figure 11 , Figure 12 shown, the axial force-bearing body 2 is of a cylindrical structure and is sleeved on the outer wall of the clamping main body 1. External threads are provided at both ends of the axial force-bearing body 2. A third stepped hole 26 and a fourth stepped hole 27 penetrating axially are provided inside the axial force-bearing body 2. Four through grooves 28 are symmetrically provided on the outer wall of the fourth stepped hole 27 to facilitate the installation and adjustment of the annular skeleton 3 through the through grooves 28. The inner wall of the fourth stepped hole 27 abuts against the outer wall of the clamping main body 1 through a sleeve 29. A clamping flange 30 that abuts against the flat section 9 of the clamping main body 1 is provided on the inner wall of the sleeve 29. The clamping flange 30 abuts and blocks between the first resisting flange 10 of the axial pressure end cover 6 and the clamping main body 1. An interval suitable for installing the annular hanger is provided between the inner wall of the fourth stepped hole 27 and the outer wall of the clamping main body 1.

[0061] As Figure 2 , Figure 13 , Figure 14 , the axial pressure cover 7 has a through stepped groove 31 inside. The axial pressure cover 7 is sleeved on the outer wall of the axial force-bearing body 2. The first resisting flange 10 of the axial pressure end cover 6 abuts against the stepped platform 32 of the stepped groove 31. The axial pressure cover 7 presses the axial pressure end cover 6 against the clamping main body 1 by being threadedly connected to the axial force-bearing body 2. The axial pressure cover 7 is made of titanium alloy, and a weight-reducing hole 33 is provided at the outer end of the axial pressure cover 7.

[0062] As Figure 2 , Figure 15As shown, the annular skeleton 3 is made of polytetrafluoroethylene and sleeved on the outer wall of the clamping body 1. The two ends are respectively abutted against the axial force body 2 through the sealing rings 34, and there is a gap between the annular skeleton 3 and the outer wall of the clamping body 1. A plurality of positioning grooves 35 suitable for accommodating the radio frequency coil are provided on the outer wall of the annular skeleton 3, and the radio frequency coil is sleeved on the annular skeleton 3. The shielding cover is connected to the outer wall of the axial force body 2 by screws, that is, it covers the outside of the radio frequency coil to prevent the radio frequency coil from radiating to the outside; an electrical connector 36 suitable for connecting with the radio frequency coil is provided on the inner wall of the shielding cover to prevent the wire from being pulled out when it is placed outside. As Figure 1 shown, the shielding cover is a cuboid frame structure, including: a housing bracket 37, an end plate 38 and a side wall plate 39.

[0063] As Figure 2 , Figure 16 , Figure 17 shown, the outer wall of the sealing ring 34 is stepped. One end is inserted between the annular skeleton 3 and the outer wall of the clamping body 1 and is hermetically connected to the clamping body 1 through a sealing ring. The other end has an abutting platform 40 suitable for abutting against the end of the annular skeleton 3. The sealing ring 34 realizes the axial limit of the annular skeleton 3. The sealing ring 34 is provided with a coolant accommodating groove 41 and a coolant injection hole 42, and the coolant injection hole 42 communicates with the coolant accommodating groove 41. A plurality of grooves 43 are provided on the inner side wall of the sealing ring 34, and the grooves 43 communicate between the coolant accommodating groove 41 and the gap between the annular skeleton 3 and the clamping body 1. The heat on the outer wall of the clamping body 1 is conducted to the annular skeleton 3 through the sealing ring 34, and the coolant cools the sealing ring 34 through the coolant injection hole 42, thereby reducing the heat conduction phenomenon; and the coolant can flow into the gap between the annular skeleton 3 and the clamping body 1 through the coolant accommodating groove 41 to cool the clamping body 1 and reduce the radiant heat to the annular skeleton 3.

[0064] Obviously, the above embodiments are only examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A holder for a nuclear magnetic resonance system, characterized in that, it includes: A clamping main body (1), made of non-metallic material, having a receiving cavity (8) for placing a sample; An annular skeleton (3), sleeved on the outer wall of the clamping main body (1), and having a gap with the outer wall of the clamping main body (1); A radio frequency coil, arranged around the outer wall of the annular skeleton (3); It further includes: an axial force-bearing body (2), sleeved on the outer walls of the clamping main body (1) and the annular skeleton (3); The interior of the axial force-bearing body (2) has a third stepped hole (26) and a fourth stepped hole (27) that penetrate axially, and four through grooves (28) are symmetrically opened on the outer wall of the fourth stepped hole (27); Sealing rings (34) are respectively arranged at both ends of the annular skeleton (3), and the sealing rings (34) are inserted between the annular skeleton (3) and the outer wall of the clamping main body (1); The sealing ring (34) has an abutting platform (40) for abutting against the end of the annular skeleton (3), and the axial force-bearing body (2) forms an abutment against the sealing ring (34); The sealing ring (34) has a coolant receiving groove (41) and a coolant injection hole (42); The coolant receiving groove (41) on the sealing ring (34) communicates with the gap between the annular skeleton (3) and the clamping main body (1).

2. The holder for a nuclear magnetic resonance system according to claim 1, characterized in that, The outer wall of the annular skeleton (3) has a positioning groove (35) suitable for accommodating the radio frequency coil.

3. The holder for a nuclear magnetic resonance system according to claim 2, characterized in that, The outer wall of the axial force-bearing body (2) has at least one through groove (28).

4. The holder for a nuclear magnetic resonance system according to any one of claims 1-3, characterized in that, it further includes: A shielding cover, detachably covering the outside of the radio frequency coil.

5. The holder for a nuclear magnetic resonance system according to claim 4, characterized in that, The shielding cover is provided with an electrical connecting member (36) suitable for connecting with the radio frequency coil.

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