US3715914A
Expired / Lapsed
US
⏱️ 0.0 years remaining
On site pressure vessel inspection device
Assignee: Babcock International Ltd
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Filing: 1970-10-12
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Granted: 1973-02-13
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Expires: 1990-10-12
Abstract
Abstract A remotely controlled method for the non-destructive inspection of the primary pressure containment means of a nuclear reactor, on the site of use, for the detection of degradation resulting from sustained exposure to radiation. This method utilizes dual probes operating on a send-and-receive basis, wherein an ultrasonic beam is sent into a thick vessel wall describing a Vlike path in the same. The transducers are fixed with respect to each other, and are transported about a programmed course in fixed relation to the vessel, so as to allow the beam to inspect 100 percent of the steel in such wall. If a defect was present in the steel, it would interfere with the path of the ultrasonic beam and a corresponding loss of energy would be detected and recorded. A comparison of the record of signals resulting from this inspection, with an established pattern of signals having its inception prior to service would indicate the initiation and propagation of a defect so that, if necessary, remedial procedures could be undertaken.
Inventors
- 👤 L Gross
- 👤 C Johnson
- 👤 S Nattsas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:30
CPC Classifications
G; G21; G21C; G21C17/00; G21C17/003; G01; G01N; G01N29/00; G01N29/04; G01N29/11; G01N2291/00; G01N2291/02; G01N2291/023; G01N2291/0234; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
147 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: establishing a precise reference signal for each of a succession of elemental regions of said pressure vessel, prior to service, in a predetermined course of precise locations on said vessel''s wall, said reference signal representing the lack of mechanical degradation in said region due to radiation, subsequently, generating and establishing a second signal for each of a series of said regions in a programmed sequence in accordance with said course of precise locations, said second signal representing the condition of said region after said vessel has been exposed to radiation for a sustained period of time, and comparing electronically said reference and said second signal to establish an indicator signal identifying those elemental regions which have degraded over said interval of time.
Claim 2
Independent Claim
147 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: establishing a precise reference signal for each of a succession of elemental regions of said pressure vessel, prior to service, in a predetermined course of precise locations on said vessel''s wall, said reference signal representing the lack of mechanical degradation in said region due to radiation, subsequently, generating and establishing a second signal for each of a series of said regions in a programmed sequence in accordance with said course of precise locations, said second signal representing the condition of said region after said vessel has been exposed to radiation for a sustained period of time, and comparing electronically said reference and said second signal to establish an indicator signal identifying those elemental regions which have degraded over said interval of time.
Claim 3
Independent Claim
147 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: establishing a precise reference signal for each of a succession of elemental regions of said pressure vessel, prior to service, in a predetermined course of precise locations on said vessel''s wall, said reference signal representing the lack of mechanical degradation in said region due to radiation, subsequently, generating and establishing a second signal for each of a series of said regions in a programmed sequence in accordance with said course of precise locations, said second signal representing the condition of said region after said vessel has been exposed to radiation for a sustained period of time, and comparing electronically said reference and said second signal to establish an indicator signal identifying those elemental regions which have degraded over said interval of time.
Claim 4
Independent Claim
147 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: establishing a precise reference signal for each of a succession of elemental regions of said pressure vessel, prior to service, in a predetermined course of precise locations on said vessel''s wall, said reference signal representing the lack of mechanical degradation in said region due to radiation, subsequently, generating and establishing a second signal for each of a series of said regions in a programmed sequence in accordance with said course of precise locations, said second signal representing the condition of said region after said vessel has been exposed to radiation for a sustained period of time, and comparing electronically said reference and said second signal to establish an indicator signal identifying those elemental regions which have degraded over said interval of time.
Claim 5
Dependent Claim
25 words
The method of claim 1 wherein said reference and said second signals are each electronically evaluAted on a separate basis and recorded prior to comparison.
Claim 6
Dependent Claim
37 words
The method of claim 1 wherein on a separated basis, said reference and said second signal are each electronically measured, addressed with respect to location of said sensors relative to said vessel, and recorded prior to comparison.
Claim 7
Dependent Claim
64 words
The method of claim 1 wherein said reference and said second signal are each electronically processed on a separate basis prior to comparison by the steps which comprise: measuring said signal, simultaneously monitoring the origin of said signal, converting said measured signal to digital data, addressing said digital data based on origin, and recording said address and data in the form of permanent copy.
Claim 8
Dependent Claim
110 words
The method of claim 1 wherein said reference signal and said second signal are each electronically processed on a separate basis prior to comparison by the steps which comprise: accepting each of said signals in the form of a video pulse whose height is proportional to the amplitude of said established signal, sorting said pulses for the lowest pulse height during a specific reception interval, selecting the most significant pulse for said interval, converting said pulse to a digitalized form of data, addressing said digitalized signal with relationship to the specific origin of said signal relative to said vessel, and presenting said data and said address in hard copy form.
Claim 9
Dependent Claim
138 words
The method of claim 1 wherein said reference and said second signal are each electronically processed on a separate basis prior to comparison by the steps which comprise: accepting each of said signals in the form of a video pulse whose height is proportional to the amplitude of said establish signal, sorting said pulses by gating means so that only the pulse of lowest height is transmitted further, integrating said transmitted pulse to provide a d-c signal whose amplitude is proportional to pulse height, converting said d-c signal to digital form, monitoring the location relative to said vessel of the means generating said initial signals, supplying an address for said digital data based on said monitoring, converting said address and digital data into serial form for transmission to an output station, and reducing said data to permanent copy.
Claim 10
Independent Claim
139 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: generating a reference signal for each of a succession of elemental regions of said pressure vessel in a predetermined course of precise locations on said vessel wall, said reference signal representing the lack of mechanical degradation in said region due to radiation, subsequently, generating a second signal for each of a series of said regions in a programmed sequence with said course of precise locations, said second signal representing the condition or said regions after said vessel has been exposed to radiation for a sustained period of time, and comparing electronically said reference and said second signal to establish an indicator signal identifying those elemental regions which have degraded over said interval of time.
Claim 11
Independent Claim
139 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: generating a reference signal for each of a succession of elemental regions of said pressure vessel in a predetermined course of precise locations on said vessel wall, said reference signal representing the lack of mechanical degradation in said region due to radiation, subsequently, generating a second signal for each of a series of said regions in a programmed sequence with said course of precise locations, said second signal representing the condition or said regions after said vessel has been exposed to radiation for a sustained period of time, and comparing electronically said reference and said second signal to establish an indicator signal identifying those elemental regions which have degraded over said interval of time.
Claim 12
Independent Claim
120 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: examining, in depth, the interior of the wall of said vessel by means of an acoustical sensor thereby establishing a reference pattern of signals characterizing the overall condition of said vessel prior to service in an environment of radiation, exposing said vessel to radiation for a sustained period of time, subsequently, scanning the elemental regions of said exposed vessel by said sensor in accordance with said reference pattern to establish a second pattern of signals, and comparing electronically said reference and second signal to detect a difference representing degradation of said vessel due to radiation.
Claim 13
Independent Claim
120 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: examining, in depth, the interior of the wall of said vessel by means of an acoustical sensor thereby establishing a reference pattern of signals characterizing the overall condition of said vessel prior to service in an environment of radiation, exposing said vessel to radiation for a sustained period of time, subsequently, scanning the elemental regions of said exposed vessel by said sensor in accordance with said reference pattern to establish a second pattern of signals, and comparing electronically said reference and second signal to detect a difference representing degradation of said vessel due to radiation.
Claim 14
Independent Claim
142 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: positioning an acoustical sensor for an initial scan of each of a series of elemental regions of said vessel thereby establishing a reference pattern of signals for said vessel, characterizing the condition of said vessel prior to service in an environment of radiation based on said pattern of signals, exposing said vessel to radiation for a sustained period of time, subsequently, scanning said elemental regions of said exposed vessel by said sensor in a programmed sequence of positions in accordance with said initial scan to generate a second pattern of signal characterizing said vessel after exposure to radiation, comparing electronically said reference and second pattern to detect a difference representing degradation of said vessel due to radiation.
Claim 15
Independent Claim
142 words
A method of inspecting a pressure vessel of a nuclear reactor to ascertain the development of mechanical degradation from exposure to excessive radiation which comprises: positioning an acoustical sensor for an initial scan of each of a series of elemental regions of said vessel thereby establishing a reference pattern of signals for said vessel, characterizing the condition of said vessel prior to service in an environment of radiation based on said pattern of signals, exposing said vessel to radiation for a sustained period of time, subsequently, scanning said elemental regions of said exposed vessel by said sensor in a programmed sequence of positions in accordance with said initial scan to generate a second pattern of signal characterizing said vessel after exposure to radiation, comparing electronically said reference and second pattern to detect a difference representing degradation of said vessel due to radiation.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |