Fuel Rod Inspection Device Using Reference Graduation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing inspection devices for fuel assemblies in nuclear plants are bulky, costly, and time-consuming, requiring specific equipment and lengthy calibration processes, which interfere with handling operations and increase operational costs.
Innovation Solution
A lightweight and compact inspection device using a digital image sensor and a boom with a reference graduation, where the bridge and lowerator provide support and displacement, allowing for rapid assembly and disassembly, and eliminating the need for bulky supporting means, with measurements taken off-line from snapshots for increased accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a bulky inspection device with specific supporting means and displacement mechanisms is used, then measurement capability is provided, but device complexity and cost increase
Solution Approach 1:
The inspection device uses the existing bridge and lowerator systems for both their original functions (assembly handling and positioning) and the additional function of supporting the inspection device. The bridge serves as both a handling mechanism and a support structure, while the lowerator provides both assembly positioning and camera displacement capability, eliminating the need for separate dedicated inspection equipment.
Solution Approach 2:
The inspection device utilizes the pool's existing infrastructure (bridge, lowerator, water pool) to provide measurement capabilities. The system serves itself by using the available resources for inspection purposes without requiring external or dedicated inspection equipment, thereby reducing overall system complexity.
2Measurement precision
If a bulky inspection device with specific supporting means is used, then measurement capability is provided, but the device occupies space and interferes with handling operations
Solution Approach 1:
The bridge and lowerator systems serve dual purposes: their original functions for assembly handling and the additional function of supporting the inspection device. This integration eliminates the need for separate bulky supporting structures that would interfere with handling operations, as the same structures used for handling also provide support for measurements.
3Measurement precision
If a traditional inspection device with calibration processes is used, then measurement accuracy is achieved, but inspection time increases
Solution Approach 1:
The patent replaces mechanical displacement measurement systems with an optical measurement system using a digital camera. Instead of mechanically displacing the camera along indexed axes and using displacement counters, the system uses optical imaging with a reference graduation scale. Measurements are taken off-line by analyzing images, eliminating the need for complex mechanical calibration and displacement counting, thereby reducing inspection time while maintaining accuracy.
4Measurement precision
If a bulky inspection device is installed in the pool, then inspection capability is provided, but decontamination becomes difficult
Solution Approach 1:
The inspection device is designed to be removable and can be taken out of the pool for decontamination. The device includes a removable fastening mechanism that allows it to be detached from the assembly and removed from the pool environment, facilitating easy decontamination compared to fixed or permanently installed inspection devices.
Data Source
AI summary
The invention relates to a device for inspecting a fuel assembly in the pool of a nuclear plant, that comprises an image sensor with an observation field, and further comprising a boom with at least one removable fastener to the assembly, a reference graduation extending along an axis parallel to a longitudinal axis of the assembly, so that the image sensor can monitor within its field both the boom and the assembly. The device is designed so that the boom can be removably attached to the fuel assembly when the latter is suspended outside the pool by the hook of the machine for handling the fuel assemblies. The invention also relates to a corresponding method.