Anti-loosening device for II-type detector in radiation monitoring system area of nuclear power plant

Abstract

The utility model relates to a nuclear power plant radiation monitoring system area II-type detector anti-loosening device which is used for anti-loosening treatment when a radiation monitoring system area II-type detector is installed, preventing foreign matter invasion when equipment is disassembled and assembled, and improving the reliability of a radiation monitoring system. A circular opening is formed in the A face of the L-shaped support and used for fixing the cylindrical detector, a cushioning gasket is fixed to the B face of the L-shaped support, meanwhile, an anti-loosening bolt is arranged on the B face, and the support and the detector are installed on a wall through the anti-loosening bolt. Operation steps of personnel are reduced, and working efficiency of the personnel is improved; equipment stability is improved, and detection reliability is guaranteed; the foreign matter event that the fixed bolt falls into the foreign matter prevention first-level area is avoided; the equipment can be matched with the bracket no matter how the equipment is replaced; and the dosage of personnel is reduced.

Description

Technical Field

[0001] This utility model relates to an anti-loosening device for a Type II area detector in a nuclear power plant radiation monitoring system. It is used to prevent loosening during the installation of the Type II area detector in the radiation monitoring system, prevent foreign objects from entering during equipment disassembly and assembly, and improve the reliability of the radiation monitoring system. Background Technology

[0002] Currently, the Type II detectors in the radiation monitoring system at the Fuqing site do not use anti-loosening devices. The equipment is directly fixed to the wall with bolts, leading to several problems on-site: 1. Low on-site work efficiency. Without anti-loosening devices, workers must constantly adjust the position to ensure correct installation. Furthermore, installation near water tanks is difficult due to the confined space, significantly increasing manpower and time, often resulting in a full day of testing without completion, thus reducing efficiency; 2. Low stability during installation and disassembly. During operation, the confined installation environment and the presence of loose parts can cause bolts to fall during detector installation and disassembly, potentially causing foreign objects to fall; 3. Impact on foreign object protection safety. The equipment is installed in a primary foreign object protection zone without reliable anti-loosening measures. Vibrations during equipment operation pose a significant risk of foreign object incidents, potentially affecting the nuclear power plant's foreign object protection safety; 4. Incompatible equipment mounting brackets. The equipment was changed from Factory 262 to Factory 719 after being replaced by other equipment. This resulted in a mismatch between the support frame and the equipment, which could lead to unstable detector installation and abnormal equipment drops. 5. Increased radiation dose to personnel. The equipment needs to be installed near the spent fuel pool and reactor during the overhaul. If the equipment's position and angle are unstable and cannot be quickly adjusted, the radiation dose rate to personnel will be greatly increased, thus increasing radiation protection costs.

[0003] The Type II area detector of the nuclear power plant radiation monitoring system is installed near the reactor and spent fuel pool to monitor radiation dose in primary foreign object protection areas such as the fuel pool area. During major overhauls of nuclear power plant units, the equipment needs to be installed on-site after the island is opened. However, the confined working environment and high foreign object protection requirements significantly increase the difficulty of equipment installation. This invention aims to ensure foreign object protection safety during equipment installation and improve the operational efficiency of personnel. It also makes subsequent operation and maintenance of the nuclear power plant radiation monitoring system more efficient and safer. Utility Model Content

[0004] Currently, the Type II area detectors in the Fuqing on-site radiation monitoring system lack anti-loosening devices, causing numerous problems in on-site operation. Because the equipment is located in the primary foreign object protection zone, the installation location of the detectors is critical. It must be ensured that the cables connecting to the processing display box can reach the detectors, and that the detectors are reliably and stably installed to effectively monitor radiation doses in the reactor and spent fuel pool areas. When contamination is detected, the monitors automatically issue audible and visual alarms.

[0005] The purpose of this utility model is to provide an anti-loosening device for the Type II area detector in a nuclear power plant radiation monitoring system, which solves the following problems encountered in the field of nuclear power plant radiation monitoring systems due to the lack of anti-loosening devices: ① loss of radiation dose measurement of reactor and spent fuel pool accessories; ② bolts for detector installation falling into the reactor or pool due to loosening during disassembly and assembly; ③ low on-site work efficiency and increased radiation dose to personnel, etc.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] A type II detector anti-loosening device for a nuclear power plant radiation monitoring system has a circular opening on surface A of an L-shaped bracket for fixing a cylindrical detector. A shock-absorbing pad is fixed on surface B of the L-shaped bracket, and anti-loosening bolts are also present on surface B. The bracket and detector are mounted on the wall using the anti-loosening bolts.

[0008] The L-shaped bracket is 18cm wide.

[0009] The L-shaped bracket has a circular opening with a diameter of 10cm on surface A.

[0010] The L-shaped bracket is made of stainless steel.

[0011] The shock-absorbing pads are square.

[0012] The shock-absorbing pads are made of plastic.

[0013] There is an anti-loosening bolt at each of the four corners on the B side of the L-shaped bracket.

[0014] The beneficial effects achieved by this utility model are as follows:

[0015] The Type II area detector of the nuclear power plant radiation monitoring system is installed near the reactor and spent fuel pool to monitor radiation dose in primary foreign object protection areas such as the fuel pool area. During major overhauls of nuclear power plant units, the equipment needs to be installed on-site after the island is opened. However, the confined working environment and high foreign object protection requirements significantly increase the difficulty of equipment installation. This invention aims to ensure foreign object protection safety during equipment installation and improve the operational efficiency of personnel. It also makes subsequent operation and maintenance of the nuclear power plant radiation monitoring system more efficient and safer.

[0016] This device features: 1) anti-loosening treatment for the detector; 2) direct disassembly and assembly with the detector, simplifying operation and improving maintenance efficiency; 3) preventing loose parts from falling into the primary foreign object protection zone. It reduces operational steps, improves work efficiency, enhances equipment stability, ensures detection reliability, prevents foreign object incidents such as fixing bolts falling into the primary foreign object protection zone, ensures compatibility with the support frame regardless of equipment replacement, and reduces the radiation dose received by personnel. Attached Figure Description

[0017] Figure 1 A front view of a type II area detector anti-loosening device in a nuclear power plant radiation monitoring system;

[0018] Figure 2 A side view of an anti-loosening device for a Type II area detector in a nuclear power plant radiation monitoring system;

[0019] Figure 3 A top view of an anti-loosening device for a Type II area detector in a nuclear power plant radiation monitoring system;

[0020] Figure 4 To prevent the bolts from loosening;

[0021] The top view shows side A, and the side view shows side B.

[0022] 1. Shock-absorbing pad; 2-11 are bolt holes, with anti-loosening bolts installed at 8-11. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0024] A type II detector anti-loosening device for a nuclear power plant radiation monitoring system comprises an 18cm wide L-shaped stainless steel bracket, a shock-absorbing pad, and four anti-loosening bolts. The A-side of the L-shaped bracket has a 10cm diameter circular opening for securing a cylindrical detector. The B-side of the L-shaped bracket is fitted with a plastic shock-absorbing pad, primarily for equipment vibration damping. Additionally, each of the four corners of the B-side has an anti-loosening bolt, which allows the bracket and detector to be mounted to a wall.

[0025] The L-shaped bracket is fixedly attached to a plastic shock-absorbing pad on one side. The detector is secured through a circular hole on the other side of the L-shaped bracket. The side of the L-shaped bracket with the plastic shock-absorbing pad is connected to the wall using four anti-loosening bolts. The detector is cylindrical. The shock-absorbing pad is square. The shock-absorbing pad is made of plastic. The bracket is made of stainless steel.

[0026] During installation, the cylindrical detector can be pre-installed at the circular opening on side A and secured with bolts before being brought to the installation site. Upon arrival, the bracket (side B) is placed against the wall, and the metal bracket, along with the detector, is secured to the wall using the four anti-loosening bolts on side B. This fixing position can be adjusted horizontally as needed. When removing the detector after a major overhaul, simply loosen the four anti-loosening bolts on side B, then remove the bracket and detector together and take them out of the site.

[0027] This anti-loosening device can effectively fix the cylindrical detector, preventing it from becoming loose or shifting due to vibration or other factors on site, thus affecting the equipment's detection efficiency. During maintenance and installation, the anti-loosening bolts allow for quick disassembly and assembly of the bracket, requiring only four bolts for stable installation, greatly improving installation efficiency and reducing the occurrence of foreign object intrusion.

[0028] By machining, a stable and reliable anti-loosening component is obtained, reducing environmental vibrations experienced by the equipment after installation on site. Using fixing bolts, the bracket base and bolts are permanently fixed as a whole, avoiding the risk of bolts falling off during equipment disassembly and assembly, and greatly reducing the possibility of foreign objects entering the system. With this anti-loosening device, the detector only requires tightening four bolts to complete the fixation on site, greatly reducing the operational difficulty and time for on-site personnel, and reducing radiation exposure. The bracket B side is permanently fixed to the vibration damping pad 1 to prevent the detector from loosening or shifting due to vibration or other factors on site, thus affecting the equipment's detection efficiency. During the work preparation stage, fixing bolts 2-7 are used to permanently fix the bracket A side and the detector as a whole, avoiding the risk of bolts falling off during temporary disassembly and assembly on site, and greatly reducing the possibility of foreign objects entering the system. After arriving at the work site, the detector with the vibration damping pad 1 is attached to the wall, and the anti-loosening bolts 8-11 are tightened to complete the fixation, greatly reducing the operational difficulty and time for on-site personnel, and reducing radiation exposure. During the equipment dismantling process, only bolts 8-11 need to be removed to remove the device along with the detector from the site.

Claims

1. A loose-tight device for a region II type probe of a nuclear power plant radiation monitoring system, characterized in that: The L-shaped bracket has a circular opening on side A for fixing a cylindrical detector. The L-shaped bracket has a shock-absorbing pad on side B, and anti-loosening bolts on side B to mount the bracket and detector to the wall.

2. The nuclear power plant radiation monitoring system Area II type probe anti-loosening device according to claim 1, characterized in that: The L-shaped bracket is 18cm wide.

3. The nuclear power plant radiation monitoring system Area II type probe anti-loosening device of claim 1, wherein: The L-shaped bracket has a circular opening with a diameter of 10cm on surface A.

4. The nuclear power plant radiation monitoring system Area II type probe anti-loosening device of claim 1, wherein: The L-shaped bracket is made of stainless steel.

5. The nuclear power plant radiation monitoring system Area II type probe anti-loosening device of claim 1, wherein: The shock-absorbing pads are square.

6. The nuclear power plant radiation monitoring system Area II type probe anti-loosening device of claim 1, wherein: The shock-absorbing pads are made of plastic.

7. The nuclear power plant radiation monitoring system Area II type probe anti-loosening device of claim 1, wherein: There is an anti-loosening bolt at each of the four corners on the B side of the L-shaped bracket.

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