Controllable source neutron generator mechanical structure

Abstract

A controllable source neutron generator mechanical structure disclosed by the present invention comprises a high-voltage transmission line, a high-voltage screw plug, a multiplying short section, an insulating shell and a transformer seat, the high-voltage transmission line is connected with a voltage multiplying short section through the high-voltage screw plug, the insulating shell is sleeved outside the high-voltage transmission line, and the insulating shell is connected with the transformer seat through a screw. The high-voltage transmission line is connected with the high-voltage screw plug connecting hole in a matched mode and is compressed through threads in the radial direction to form a small assembly. The high-pressure plug screw and the upper end of the multiplying nipple are positioned through a special-shaped shaft shoulder, the end faces are aligned, a radial screw is fixed to form a high-pressure transmission line, and the high-pressure plug screw and the multiplying nipple are consistent in axial direction. Then, a large assembly composed of the high-voltage transmission line, the high-voltage plug screw and the multiplication short section is positioned and connected with a center special-shaped hole of the transformer in a matched mode through a special-shaped shaft shoulder at the lower end of the multiplication short section, end faces are aligned, and the neutron generator core shaft core is formed through radial fixing by screws. In the whole assembling process, all components only move in the axial direction in one direction, rotation and reciprocating are avoided, and the assembling process is simplified.

Description

Technical Field

[0001] The present invention belongs to the field of nuclear logging in oil exploration, and particularly relates to a novel mechanical structure of a controllable source neutron generator. Background Art

[0002] A controllable source neutron generator is a radioactive instrument. The structure of the controllable source neutron generator mainly includes a neutron tube, an insulating shell, a multiplication short section, and a transformer. Each component is connected by threads.

[0003] The current is regulated to a high voltage of 110 kV through the multiplication short section and transmitted to the neutron tube through a high-voltage transmission line, thereby generating neutron rays. Due to the inherent volume limitation, the high-voltage transmission line is offset at the lower end of the instrument axis. The high-voltage transmission line is a wrapped wire with a diameter of about 8 mm and a length of 400 mm. The inner core is a copper rod with a diameter of 2 mm, and the outside is tightly wrapped with a polyimide film in circles until the outer diameter reaches 8 mm to ensure the insulation of 110 kV high voltage. Since this process is manual operation, the edge sealing of the polyimide film is not particularly firm, and it is easy to peel and wrinkle, reducing the insulation performance. Multiple wire harnesses also need to be arranged axially and radially inside the generator to ensure power transmission, communication, and control functions. Therefore, there are requirements for the axial direction consistency of multi-component assembly to meet the wiring needs. The overall process must solve the problems of high-voltage insulation in a narrow space, correct connection and firm reliability of each component. It is necessary to assemble as many components in place at one time as possible to avoid peeling and wrinkling of the insulation layer caused by repeated trial assembly, and the decrease in insulation performance leading to high-voltage current leakage and creeping phenomenon, resulting in poor reliability and unstable operation of the whole machine. The existing mechanical structure remains in the technical state of the 1990s, and there are the following defects in the design of the directional connection and assembly between the multiplication short section and its accessory components:

[0004] 1. Four components, namely the multiplication short section, the high-voltage plug, the insulating shell, and the transformer base, are connected by threads. Due to the uncontrollability of the threads, after the four are connected, their respective axial states are uncontrollable, and it is difficult to unify the direction in wiring. It is necessary to continuously extract the multiplication short section and rotate to adjust the high-voltage plug. Therefore, the assembly process is cumbersome. Even if the adjustment is in place, it will cause an axial gap between the multiplication short section and the high-voltage plug, reducing the electrical connection reliability and overall seismic resistance.

[0005] 2. The upper and lower ends of the multiplication short section are threaded structures and are spirally connected to the upper and lower components. This easily causes the axial position of the high-voltage transmission line to be uncertain, so that it is inconsistent with the eccentric wire passing hole of the insulating shell, and it is necessary to frequently adjust the position of the high-voltage transmission line, resulting in wrinkles in the outer insulating layer of the insulated wire, reducing the insulation performance and causing high-voltage current creeping phenomenon.

[0006] 3. The high-pressure plug and the multiplier sub-section are connected in a spiral manner, and the high-pressure output end of the multiplier sub-section is pressed tightly against the end face of the skeleton by the thread of the high-pressure plug. Since the multiplier sub-section is a high-temperature insulating non-metal, the strength and self-lubricity of the thread do not match those of the metal, and the pressing force of the fit is prone to looseness under the downhole high-temperature and vibration environment, resulting in loose connection. Summary of the Invention

[0007] In view of the deficiencies in the mechanical design of the current controllable-source neutron generator, this invention adopts the concept of special-shaped positioning and originally innovatively designs a new type of multiplier sub-section, high-pressure plug, insulating housing, and transformer base to form a new structure of the controllable-source neutron generator. It solves the technological problems of the directional assembly of four components: the high-pressure transmission line, the multiplier sub-section, the insulating housing, and the transformer base.

[0008] This invention includes a high-pressure transmission line, a high-pressure plug, a multiplier sub-section, an insulating housing, and a transformer base. The high-pressure transmission line is connected to the multiplier sub-section through the high-pressure plug, and an insulating housing is sleeved outside. The insulating housing is connected to the transformer base through screws.

[0009] The high-pressure transmission line is mated with the connection hole of the high-pressure plug, and the radial direction is pressed tightly by the thread to form a small component. The high-pressure plug and the upper end of the multiplier sub-section are positioned by a special-shaped shaft shoulder, the end faces are aligned, and the radial screws are fixed to make the high-pressure transmission line, the high-pressure plug, and the multiplier sub-section point in the same axial direction. Then, the large component composed of the high-pressure transmission line, the high-pressure plug, and the multiplier sub-section is used to position and mate with the special-shaped hole at the center of the transformer by the special-shaped shaft shoulder at the lower end of the multiplier sub-section, the end faces are aligned, and the radial screws are fixed to form the core axis of the neutron generator.

[0010] The core axis is installed in the insulating housing. First, the high-pressure transmission line is slowly inserted into the offset through-hole in the insulating housing. After reaching the inner hole end face, the radial threaded hole at the end of the transformer base is exactly aligned with the radial through-hole at the lower end of the insulating housing, and they are connected and fixed with screws. Through the above innovative design, when the four components of the high-pressure transmission line, the multiplier sub-section, the insulating housing, and the transformer are assembled, the axes of the multiplier sub-section and the high-pressure transmission line are coplanar. Taking this coplanarity as the reference, the purpose of a unified interface is achieved at the relevant positioning and connection positions with the insulating housing and the transformer. It achieves simple and convenient assembly, and the process is smooth. It avoids the reduction of insulation performance caused by the wrinkles and peeling of the insulation layer due to multiple trial assemblies, and the occurrence of high-voltage current creepage phenomenon.

[0011] To solve the technological problems of the directional assembly of the four components of the high-pressure transmission line, the multiplier sub-section, the insulating housing, and the transformer base, and to solve three types of defects in the original design, innovative structural designs are carried out on the above relevant components. The special-shaped positioning design is adopted to make them remain on the same interface axis after the final assembly, with reliable and stable positioning, completely avoiding axial and radial displacements, and ensuring the electrical connection reliability and the seismic resistance of the instrument from the structure.

[0012] With the structural design of the present invention, during the entire assembly process, each component only moves in one axial direction, without rotation or reciprocation, simplifying the assembly process. It avoids the wrinkles on the outer insulation layer of the insulated wire caused by repeated adjustments in the past, reduces the insulation performance, and triggers the phenomenon of high-voltage current creepage. At the same time, all screw pairs use homogeneous materials, and the strength and self-lubrication degree of the threads are perfectly matched, avoiding the hidden danger of loosening of the connection under the downhole high-temperature and vibration environment. Brief Description of the Drawings

[0013] Figure 1 is the structural schematic diagram of the present invention

[0014] Figure 2 is the assembly schematic diagram of the present invention

[0015] Figure 3 is the multiplier sub-section of the present invention;

[0016] Figure 4 is the high-voltage plug of the present invention;

[0017] Figure 5 is the insulating housing of the present invention;

[0018] Figure 6 is the transformer base of the present invention. Detailed Description of the Invention

[0019] Referring to Figure 1 、 Figure 2 As shown, for the high-voltage transmission line, high-voltage plug, multiplier sub-section, insulating housing and transformer base, the high-voltage transmission line is connected to the multiplier sub-section through the high-voltage plug, and an insulating housing is sleeved outside, and the insulating housing is connected to the transformer base by screws.

[0020] Referring to Figure 3 As shown, two different-sized special-shaped positioning shoulders are designed at both ends of the multiplier sub-section, which is a combination of an arc and a plane to maintain the orientation consistency of the mating parts.

[0021] Referring to Figure 4 As shown, the middle hole of the high-voltage plug is a special-shaped positioning hole, which is matched with one end of the special-shaped shoulder of the multiplier sub-section and fixed at both ends with screws. The high-voltage transmission line is inserted into the high-voltage transmission line connection hole and fixed at both ends with screws. Since the positions of the middle special-shaped hole and the transmission line connection hole are fixed, it ensures the correct axial coplanar pointing of the high-voltage transmission line after the correct assembly of the high-voltage plug and the multiplier sub-section.

[0022] Referring to Figure 5 As shown, innovative design of the insulating housing: the connection position between the insulating housing and the transformer is a radial positioning through-hole, which is connected with a setscrew.

[0023] Referring to Figure 6As shown, the connection between the transformer base and the insulating housing is designed as a radially positioned screw hole and fixed with four screws radially; the connection with the multiplier short section is designed as a central special-shaped positioning hole and fixed with screws at both ends.

[0024] The high-voltage transmission line 1 is inserted into the connection hole at the lower end of the high-voltage plug 2 and pressed tightly by threads to form a sub-assembly. The high-voltage plug 2 is positioned with the upper end of the multiplier short section 3 through a special-shaped shoulder, and then connected with screws to make the high-voltage transmission line 1, the high-voltage plug 2 and the multiplier short section 3 coplanar axially and fixed in direction. Then, the assembly composed of the high-voltage transmission line 1, the high-voltage plug 2 and the multiplier short section 3 is connected to the transformer base 5. The special-shaped shoulder at the lower end of the multiplier short section 3 is mated with the central special-shaped hole of the transformer base 5 and fixed radially with screws. Next, the above-connected assembly is installed into the insulating housing 4. First, the high-voltage transmission line 1 is passed through the offset hole of the insulating housing 4. When the high-voltage plug 2 contacts the inner hole end face of the insulating housing 4 and the radial threaded hole on the outer diameter of the transformer base 5 is exactly aligned with the radial through hole at the lower end of the insulating housing 4, it is fixed with screws. The whole assembly process moves axially in one direction only, without rotation and reciprocation, and is completed in one step.

Claims

1. A mechanical structure of a controllable source neutron generator, characterized in that It includes a high-voltage transmission line, a high-voltage plug, a voltage multiplier sub-section, an insulating housing, and a transformer base. The high-voltage transmission line is connected to the voltage multiplier sub-section through the high-voltage plug, and an insulating housing is sleeved outside. The insulating housing is connected to the transformer base by screws.

2. The mechanical structure of a controllable source neutron generator according to claim 1, characterized in that, The high-voltage transmission line is mated with the connection hole of the high-voltage plug, and a small component is formed by radial compression with threads.

3. The mechanical structure of a controllable source neutron generator according to claim 1, characterized in that, The high-voltage plug is positioned with the upper end of the voltage multiplier sub-section through a special-shaped shoulder, the end faces are flush, and they are fixed by radial screws to make the high-voltage transmission line, the high-voltage plug, and the voltage multiplier sub-section point in the same axial direction.

4. A mechanical structure of a controllable source neutron generator according to claim 3, characterized in that, The high-voltage transmission line, the high-voltage plug, and the voltage multiplier sub-section are assembled into a large component.

5. The mechanical structure of a controllable source neutron generator according to claim 1, characterized in that, The lower end of the voltage multiplier sub-section is positioned and mated with the special-shaped hole in the center of the transformer through a special-shaped shoulder, the end faces are flush, and they are fixed by radial screws to form the core axis of the neutron generator.

6. The mechanical structure of a controllable source neutron generator according to claim 1, wherein, The high-voltage transmission line is aligned with the offset through-hole in the insulating housing and inserted.

7. The mechanical structure of a controllable source neutron generator according to claim 1, characterized in that, The core axis of the neutron generator is inserted into the insulating housing.

8. The mechanical structure of a controllable source neutron generator according to claim 1, characterized in that, The radial threaded hole at the end of the transformer base is aligned with the radial through-hole at the lower end of the insulating housing, and they are connected and fixed by screws.

9. The mechanical structure of a controllable source neutron generator according to claim 1, characterized in that, The axes of the voltage multiplier sub-section and the high-voltage transmission line are coplanar. Based on this coplanar plane, a unified interface is achieved at the relevant positioning and connecting positions with the insulating housing and the transformer.

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