A multi-stage nuclear detection device

Abstract

The present application relates to the field of nuclear detection technology, and more specifically, to a multi-section nuclear detection device, including a shock absorbing mechanism, a first detector, a bearing mechanism, a second detector, and a supporting mechanism connected in sequence from top to bottom, wherein: the shock absorbing mechanism is arranged at the top, and a first insulating ceramic is arranged between the shock absorbing mechanism and the first detector; the bearing mechanism is arranged between the first detector and the second detector; the supporting mechanism is connected to the second detector and arranged at the bottom. The present application designs a multi-section detector structure that is easy to disassemble and assemble, and has a stable connection, which greatly reduces the time for disassembly and assembly, has complete shock absorbing components, can effectively reduce the vibration and impact of the detector, uses ceramic insulating blocks to completely separate the detection device from other installation mechanisms, has good insulation performance, and overcomes signal crosstalk. In addition, a moderator bearing structure is also arranged to effectively prevent the moderator from softening, deforming, squeezing, and leaking.

Description

Technical Field

[0001] The present application relates to the field of nuclear detection technology, and in particular to a multi-stage nuclear detection device. Background Art

[0002] Nuclear measurement is an important system for monitoring nuclear reactor power. It measures the neutron flux level escaping from the reactor pressure vessel through neutron detector assemblies arranged around the reactor to provide real-time power level and change trend of the reactor, providing support for the operation of the nuclear reactor.

[0003] Traditional nuclear power plant nuclear measurement detector assemblies are mostly hoisted. The reactor is located below the refueling pool. Therefore, a wellhead is opened at the bottom of the refueling pool, and the detector assembly is hoisted into the installation channel below the wellhead in advance, and then the wellhead is sealed. Since the refueling pool needs to be filled with water to shield the radiation during the refueling of the nuclear power plant, there is a risk of leakage at the wellhead. In order to improve safety, new nuclear power plants no longer open from the refueling pool, but reserve installation holes at the bottom of the reactor, and install them in the metal channel from bottom to top. The space at the bottom of the reactor is small, and the entire detector assembly cannot be placed in the installation channel at one time, and can only be assembled in sections. Nuclear measurement detector assemblies need to consider multiple factors such as radiation resistance, low neutron activation, electrical insulation, earthquake resistance, and resistance to high temperature and high pressure steam. The structure is complex and the installation takes a long time. After the nuclear power plant is put into operation, the radiation dose at the bottom of the reactor is high due to neutron activation, and personnel cannot work for a long time.

[0004] Existing multi-section extra-core nuclear detection detectors are connected by screws, which are extremely time-consuming to install and disassemble. It takes about half an hour to disassemble a single section. After the reactor is started, the environmental radiation dose is high. In order to protect operators from the effects of long-term ionizing radiation, the manual operation time required for disassembly and assembly of the detector should be minimized. In addition, the shock-absorbing structure of the nuclear detector is unreliable. The top end is suspended in the air, which causes a large swing when vibration occurs and collides with the outer installation tube. This collision will cause the overall reliability of the detector to decrease. At the same time, the insulation effect between the supporting structures is poor. Summary of the invention

[0005] The main purpose of the present application is to provide a multi-stage nuclear detection device, comprising a shock absorbing mechanism, a first detector, a bearing mechanism, a second detector and a supporting mechanism connected in sequence from top to bottom, wherein: the shock absorbing mechanism is arranged at the top, and a first insulating ceramic is arranged between the shock absorbing mechanism and the first detector; the bearing mechanism is arranged between the first detector and the second detector; the supporting mechanism is connected to the second detector and is arranged at the bottom.

[0006] Furthermore, the shock absorbing mechanism includes a shock absorbing base, a spring steel shock absorbing plate and an insulating partition screw. The spring steel shock absorbing plate is fixed around the shock absorbing base, and the insulating partition screw is used to fix the first insulating ceramic.

[0007] Furthermore, the interior of the first detector and the second detector both include polyethylene, a fixing device, a detection device, a spring and a docking slot, wherein: the polyethylene is fixed to the inner wall of the detector by the fixing device and the spring; the detection device is arranged in the middle of the detector; and the docking slot is arranged at the bottom of the detector.

[0008] Furthermore, a first docking buckle is provided on the top of the supporting mechanism and is matched and connected with the docking slot of the first detector.

[0009] Furthermore, the bearing mechanism also includes a cable clamping trough, a cable management device and a cable clamping and fixing device.

[0010] Furthermore, a second insulating ceramic is arranged between the supporting mechanism and the second detector.

[0011] Furthermore, a second docking buckle is provided on the top of the supporting mechanism, which is matched and connected with the docking slot of the second detector.

[0012] Furthermore, the supporting mechanism also includes a cable clamping trough, a cable management device and a cable clamping and fixing device.

[0013] The multi-stage nuclear detection device provided by the present invention has the following beneficial effects:

[0014] The present application designs a multi-section detector structure that is easy to disassemble and assemble and has a firm connection, which greatly reduces the disassembly and assembly time. It has complete shock-absorbing components that can effectively reduce the vibration and impact on the detector. Ceramic insulating blocks are used to completely separate the detection device from other installation mechanisms. The insulation performance is good and signal crosstalk is overcome. In addition, a moderator bearing structure is also provided to effectively prevent the moderator from softening, deforming, squeezing and leaking. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting a part of this application are used to provide a further understanding of this application, so that other features, purposes and advantages of this application become more obvious. The schematic embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0016] Figure 1 is a schematic diagram of a multi-stage nuclear detection device provided according to an embodiment of the present application;

[0017] Figure 2 is a schematic diagram of a shock absorbing mechanism provided according to an embodiment of the present application;

[0018] Figure 3 is a schematic diagram of a first docking buckle of a carrying mechanism provided according to an embodiment of the present application;

[0019] Figure 4is a first schematic diagram of the bottom of the supporting mechanism provided according to an embodiment of the present application;

[0020] Figure 5 is a schematic diagram of the interior of a first detector provided according to an embodiment of the present application;

[0021] Figure 6 is a second schematic diagram of the bottom of the carrying mechanism provided according to an embodiment of the present application;

[0022] In the figure: 1- shock absorbing mechanism, 11- shock absorbing base, 12- spring steel shock absorbing plate, 13- insulating partition screw, 2- first detector, 21- polyethylene, 22- fixing device, 23- detecting device, 24- spring, 25- docking slot, 3- bearing mechanism, 31- first docking buckle, 32- cable clamping slot, 33- cable clamping fixing device, 4- second detector, 5- supporting mechanism, 6- first insulating ceramic, 7- second insulating ceramic. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0024] like Figure 1-6 As shown, the present application provides a multi-stage nuclear detection device, including a shock absorbing mechanism 1, a first detector 2, a bearing mechanism 3, a second detector 4 and a supporting mechanism 5 connected in sequence from top to bottom, wherein: the shock absorbing mechanism 1 is arranged at the top, and a first insulating ceramic 6 is arranged between the shock absorbing mechanism 1 and the first detector 2; the bearing mechanism 3 is arranged between the first detector 2 and the second detector 4; the supporting mechanism 5 is connected to the second detector 4 and is arranged at the bottom.

[0025] Specifically, the multi-stage nuclear detection device provided in the embodiment of the present application measures the thermal neutron flux around the reactor by means of a number of neutron detectors arranged around the reactor pressure vessel, thereby calculating the real-time power of the reactor. In the embodiment of the present application, two detectors are preferably used, and the shock absorbing mechanism 1, the first detector 2, the bearing mechanism 3, the second detector 4 and the supporting mechanism 5 are all arranged in a cylindrical shape, and are sleeved and clamped with each other. The thermal neutron flux at different positions can be detected by the arrangement of the first detector 2 and the second detector 4, so that the measurement result is more accurate. The shock absorbing mechanism 1 is mainly used to reduce the vibration and impact of the detector during the detection process. The bearing mechanism 3 is arranged between the first detector 2 and the second detector 4, and the multi-section detector can be quickly installed and connected, which greatly reduces the time for disassembly and assembly. The supporting mechanism 5 is arranged at the bottom of the device, and is mainly used to fix the multi-section detector above the supporting mechanism to ensure that the detector can work stably. The first insulating ceramic 6 is preferably a zirconia insulating ceramic block, which insulates the first detector 2 from the shock absorbing mechanism 1 at the top, has good insulation performance, overcomes signal crosstalk, and strengthens the strength of the overall detection device 23 to a certain extent.

[0026] Further, such as Figure 2 As shown, the shock absorbing mechanism 1 includes a shock absorbing base 11, a spring steel shock absorbing sheet 12 and an insulating partition screw 13. The spring steel shock absorbing sheet 12 is fixedly surrounded on the shock absorbing base 11, and the insulating partition screw 13 is used to fix the first insulating ceramic 6. The shock absorbing base 11 is mainly used to maintain the stability of the detector and reduce the vibration and impact of the detector. The spring steel shock absorbing sheet 12 can keep the top of the detector in contact with the installation pipe, thereby reducing the flexible swing. The insulating partition screw 13 can be set in two groups, upper and lower, according to actual conditions, to clamp the first insulating ceramic 6 in the center to ensure the insulation performance of the first detector 2.

[0027] Further, such as Figure 5 As shown, the interior of the first detector 2 and the second detector 4 both include polyethylene 21, a fixing device 22, a detection device 23, a spring 24 and a docking slot 25, wherein: the polyethylene 21 is fixed to the inner wall of the detector by the fixing device 22 and the spring 24; the detection device 23 is arranged in the middle of the detector; and the docking slot 25 is arranged at the bottom of the detector. The detection device 23 of the first detector 2 and the second detector 4 is arranged in the middle of the interior, and is used to detect the thermal neutron flux. In addition, high-density polyethylene 21 is also arranged inside, which is mainly used to moderate neutrons. The high-density polyethylene 21 can withstand a high working temperature of about 200 degrees without melting, and has good performance. It is fixed to the sensitive area of ​​the inner wall of the detector by the fixing device 22 and the spring 24. Through this structure, the moderator can be given appropriate expansion space, thereby improving the problem of deformation and leakage of the moderator of the traditional detector.

[0028] Further, such as Figure 3 As shown, a first docking buckle 31 is provided on the top of the supporting mechanism 3, which is matched and connected with the docking slot 25 of the first detector 2. The first docking buckle 31 of the supporting mechanism 3 is matched and connected with the docking slot 25 at the bottom of the first detector 2. When in use, the assembly and docking can be directly performed, which ensures quick alignment during connection and saves time and effort.

[0029] Furthermore, the bearing mechanism 3 also includes a cable clamping groove 32, a wire management device and a cable clamping and fixing device 33. The bearing mechanism 3 also has the function of arranging and leading out the cables. The cables led out of the first detector 2 first pass through the cable clamping groove 32 to prevent the armored cables from twisting and interfering with the overall installation of the first detector 2, and then are arranged by the internal wire management device. Finally, the neat cables are fixed and led out to the inside of the second detector 4 through the cable clamping and fixing device 33 to prevent the pulling and vibration during the traction process from affecting the stability of the welding point.

[0030] Furthermore, a second insulating ceramic 7 is provided between the supporting mechanism 3 and the second detector 4. The second insulating ceramic 7 is also preferably a zirconia insulating ceramic block, which is fixed by two sets of upper and lower insulating partition screws to insulate the supporting mechanism 3 from the second detector 4. It has high strength and good seismic resistance, and can well cope with vibrations inside the reactor compartment and possible earthquakes outside, greatly improving safety.

[0031] Furthermore, a second docking buckle is provided on the top of the support mechanism 5, which is matched and connected with the docking slot of the second detector 4. The second docking buckle of the support mechanism 5 is matched and connected with the docking slot at the bottom of the second detector 4. When in use, the assembly and docking can be directly performed, which ensures quick alignment during connection and saves time and effort.

[0032] Furthermore, the support mechanism 5 also includes a cable clamping groove, a cable management device and a cable clamping and fixing device. The support mechanism 5 also has the function of arranging and leading out the cables. The cables led out of the second detector 4 first pass through the cable clamping groove, and then are arranged by the internal cable management device. Finally, the neat cables are fixed and led out to the external control system through the cable clamping and fixing device.

[0033] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A multi-stage nuclear detection device, characterized in that: It includes a shock absorbing mechanism, a first detector, a bearing mechanism, a second detector and a supporting mechanism connected in sequence from top to bottom, wherein: The shock absorbing mechanism is arranged at the top, and a first insulating ceramic is arranged between the shock absorbing mechanism and the first detector; The bearing mechanism is arranged between the first detector and the second detector; The supporting mechanism is connected to the second detector and is arranged at the bottom; The shock absorbing mechanism, the first detector, the bearing mechanism, the second detector and the supporting mechanism are all arranged in a cylindrical shape; The first detector and the second detector both include polyethylene, a fixing device, a detection device, a spring and a docking slot, wherein: The polyethylene is fixed to the inner wall of the detector through the fixing device and the spring; The detection device is arranged in the middle of the detector; The docking slot is arranged at the bottom of the detector; A first docking buckle is provided on the top of the carrying mechanism and is matched and connected with the docking slot of the first detector; The bearing mechanism also includes a cable clamping slot, a cable management device and a cable clamping and fixing device; A second docking buckle is provided on the top of the support mechanism, and is matched and connected with the docking slot of the second detector; The supporting mechanism also includes a cable clamping groove, a cable management device and a cable clamping and fixing device.

2. The multi-stage nuclear detection device according to claim 1, characterized in that: The shock absorbing mechanism includes a shock absorbing base, a spring steel shock absorbing sheet and an insulating partition screw. The spring steel shock absorbing sheet is fixedly surrounded on the shock absorbing base, and the insulating partition screw is used to fix the first insulating ceramic.

3. The multi-stage nuclear detection device according to claim 1, characterized in that: A second insulating ceramic is arranged between the supporting mechanism and the second detector.

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