Hall Probe Yoke Layout for Quantitative Pipe Defect Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional inspection probes are limited in size, making it difficult to achieve the necessary magnetic flux density for quantitative defect measurement in small-diameter or thick magnetic members.
Innovation Solution
A defect measuring device with a yoke configuration that includes a large-diameter yoke and a magnetic sensor, allowing for the formation of a magnetic circuit that achieves the required magnetic flux density, enabling quantitative defect measurement in small-diameter or thick magnetic members.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a small-diameter magnet is used in the inspection probe, then the probe can be used on small-diameter magnetic members, but the magnetic flux density is insufficient for quantitative defect measurement
Solution Approach 1:
The patent introduces a yoke component that extends the magnetic circuit in a spatial dimension, creating a larger magnetic flux path that includes both a first counter surface (facing the magnetic member) and a second counter surface (closer to the magnetic member). This dimensional extension allows the magnetic flux density to be enhanced at the measurement location without increasing the magnet size, thereby enabling quantitative defect measurement on small-diameter magnetic members.
2Measurement precision
If a larger magnet is used to increase magnetic flux density, then quantitative defect measurement becomes possible, but the inspection probe cannot be applied to small-diameter magnetic members
Solution Approach 1:
The yoke is divided into multiple surfaces (first counter surface and second counter surface) with different functions. The first counter surface faces the magnetic member while the second counter surface is positioned closer to enable magnetic flux concentration. This segmentation allows the magnetic circuit to achieve high flux density at the measurement point without requiring a large magnet, thus maintaining probe compactness for small-diameter member inspection.
3Stress or pressure
If the magnet size is increased, then the magnetic flux density increases, but the probe size exceeds the limitation for small-diameter members
Solution Approach 1:
The yoke acts as an intermediary component between the magnet and the magnetic member. It contains and directs the magnetic flux through its magnetic circuit, concentrating the flux at the second counter surface which is positioned close to the magnetic member. This intermediary structure enables high magnetic flux density at the measurement point without requiring a large magnet, thus keeping the probe size within limits for small-diameter member inspection.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables accurate quantitative measurement of defects in small-diameter or thick magnetic members by optimizing the magnetic flux density within the magnetic circuit.
Implementation Method 1
a magnetic sensor which is configured to be located between the yoke and the magnetic member and which is configured to detect a density of magnetic flux flowing in a magnetic circuit
Data Source
Figure 1
Figure 2(a)~2(c)
Figure 3
AI summary
An inspection probe (100) includes a Hall element (3) which detects the density of magnetic flux flowing in a magnetic circuit formed by a yoke (1), a magnet (2), and a magnetic pipe (P). A second outer circumferential surface (12a) of the yoke (1) is arranged to be located closer to the magnetic pipe (P) than a first outer circumferential surface (11a) of the yoke (1) is to the magnetic pipe (P).