Nondestructive test system comprising a neutron emission unit for emitting fast neutrons and a neutron detection unit for detecting thermal neutrons, and nondestructive test method

Patent metadata

Field	Value
Publication number	US-11754516-B2
Application number	US-202017310845-A
Country	US
Kind code	B2
Filing date	Feb 27, 2020
Priority date	Feb 27, 2019
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

A neutron emission unit is configured to emit neutrons such that a center axis (Nh) of a neutron emission intersects a center axis direction of collimators ( 23 a to 23 e). A calculation unit is capable of generating information about an inspection object in the center axis direction of the collimators, based on position information of a neutron detector and/or position information of the neutron emission unit, information about an angle (θ 1 ) at which the center axis of the neutron emission intersects the center axis direction of the collimators, and a neutron amount detected by the neutron detector.

First claim

The invention claimed is:

1. A non-destructive inspection system, comprising:
a neutron emission unit capable of emitting neutrons;
a neutron detector capable of detecting the neutrons emitted from the neutron emission unit and penetrating through an inspection object;
a collimator positioned between the inspection object and the neutron detector and arranged so that the neutrons penetrating through the inspection object enter the neutron detector with a predetermined directivity; and
a calculation unit configured to perform a calculation based on a result detected by the neutron detector,
wherein:
the neutron emission unit emits the neutrons such that a center axis of a neutron emission intersects a center axis direction of the collimator, and
the calculation unit is capable of generating information about the inspection object in the center axis direction of the collimator, based on position information of the neutron detector and/or position information of the neutron emission unit, information about an angle at which the center axis of the neutron emission intersects the center axis direction of the collimator, and a neutron amount detected by the neutron detector.

2. The non-destructive inspection system of claim 1 , wherein the neutron emission unit is configured to emit the neutrons such that the center axis of the neutron emission intersects the center axis direction of the collimator at the angle of 10 degrees to 80 degrees.

3. The non-destructive inspection system of claim 2 , wherein:
the neutron detector comprises a plurality of detection units,
the calculation unit specifies a detection unit, out of the plurality of detection units, which detects a peculiar neutron amount based on neutron amounts detected by the plurality of detection units.

4. The non-destructive inspection system of claim 2 , wherein:
the neutron emission unit is capable of emitting the neutrons toward a first position and a second position, which are differently distanced from the collimator in the center axis direction of the collimator,
the neutron detector is capable of detecting a first neutron amount detected when the neutron emission unit emits the neutrons toward the first position and a second neutron amount detected when the neutron emission unit emits the neutrons toward the second position, and
the calculation unit is capable of generating information about the inspection object between the first position and the second position based on the first neutron amount and the second neutron amount.

5. The non-destructive inspection system of claim 1 , wherein:
the neutron detector comprises a plurality of detection units,
the calculation unit specifies a detection unit, out of the plurality of detection units, which detects a peculiar neutron amount based on neutron amounts detected by the plurality of detection units.

6. The non-destructive inspection system of claim 5 , wherein the calculation unit generates a fitting curve based on the neutron amounts detected by the plurality of detection units, and specifies the detection unit that detects the peculiar neutron amount based on a difference between the fitting curve and a neutron amount detected by each of the plurality of detection units.

7. The non-destructive inspection system of claim 6 , wherein:
the neutron emission unit is capable of emitting the neutrons toward a first position and a second position, which are differently distanced from the collimator in the center axis direction of the collimator,
the neutron detector is capable of detecting a first neutron amount detected when the neutron emission unit emits the neutrons toward the first position and a second neutron amount detected when the neutron emission unit emits the neutrons toward the second position, and
the calculation unit is capable of generating information about the inspection object between the first position and the second position based on the first neutron amount and the second neutron amount.

8. The non-destructive inspection system of claim 5 , wherein the calculation unit specifies the detection unit that detects the peculiar neutron amount based on a difference between standard information corresponding to material information of the inspection object and a neutron amount detected by each of the plurality of detection units.

9. The non-destructive inspection system of claim 8 , wherein:
the neutron emission unit is capable of emitting the neutrons toward a first position and a second position, which are differently distanced from the collimator in the center axis direction of the collimator,
the neutron detector is capable of detecting a first neutron amount detected when the neutron emission unit emits the neutrons toward the first position and a second neutron amount detected when the neutron emission unit emits the neutrons toward the second position, and
the calculation unit is capable of generating information about the inspection object between the first position and the second position based on the first neutron amount and the second neutron amount.

10. The non-destructive inspection system of claim 5 , wherein:
the neutron emission unit is movable relatively to the inspection object, and
the calculation unit specifies the detection unit that detects the peculiar neutron amount, based on the neutron amounts detected by the plurality of detection units before a movement of the neutron emission unit and the neutron amounts detected by the plurality of detection units after the movement of the neutron emission unit.

11. The non-destructive inspection system of claim 5 , wherein:
the neutron emission unit is capable of emitting the neutrons toward a first position and a second position, which are differently distanced from the collimator in the center axis direction of the collimator,
the neutron detector is capable of detecting a first neutron amount detected when the neutron emission unit emits the neutrons toward the first position and a second neutron amount detected when the neutron emission unit emits the neutrons toward the second position, and
the calculation unit is capable of generating information about the inspection object between the first position and the second position based on the first neutron amount and the second neutron amount.

12. The non-destructive inspection system of claim 1 , wherein:
the neutron emission unit is capable of emitting the neutrons toward a first position and a second position, which are differently distanced from the collimator in the center axis direction of the collimator,
the neutron detector is capable of detecting a first neutron amount detected when the neutron emission unit emits the neutrons toward the first position and a second neutron amount detected when the neutron emission unit emits the neutrons toward the second position, and
the calculation unit is capable of generating information about the inspection object between the first position and the second position based on the first neutron amount and the second neutron amount.

13. The non-destructive inspection system of claim 12 , wherein
the neutron emission unit is configured to emit the neutrons to the first position and the second position by changing relative positions of the neutron detector and the neutron emission unit.

14. The non-destructive inspection system of claim 12 , wherein
the neutron emission unit is configured to emit the neutrons to the first position and the second position by changing an emitting direction of the neutrons emitted from the neutron emission unit.

15. The non-destructive inspection system of claim 12 , wherein

Assignees

• Topcon Corp
• Riken

Inventors

• Tsukada Hisashi
• Nagano Shigenori
• Otake Yoshie
• Sunaga Hideyuki
• Yoshimura Yuichi
• IKADO Koji

Classifications

• G01N23/204 Primary

  using neutrons · CPC title

• G01N23/20

  by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials · CPC title

• G01N2223/1066

  thermal · CPC title

• G01N2223/316

  collimators · CPC title

• G01N2223/646

  flaws, defects · CPC title