US4008603A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrasonic method and apparatus for measuring wall thickness of tubular members
Assignee: Shell USA Inc
•
Filing: 1975-12-29
•
Granted: 1977-02-22
•
Expires: 1995-12-29
Abstract
Abstract A method and apparatus for measuring the wall thickness of tubular members using pulses of ultrasonic energy and measuring the time interval between the echoes from the two surfaces of the wall. A rotating diagonal reflector in combination with a fixed transducer is used to scan the interior of the member with the time between the echo from the inner and outer surfaces of the wall being used as a measure of the wall thickness. Each of the time measurements is assigned to a particular counter to accumulate all measurements of a particular thickness. This provides a profile of the wall thickness of the tubular member.
Inventors
- 👤 George T. Paulissen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 17:37
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/04; G01N29/07; G01B; G01B17/00; G01B17/02; G01N2291/00; G01N2291/02; G01N2291/028; G01N2291/02854; Y; Y10; Y10S; Y10S73/00; Y10S73/901
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
79 words
A method for measuring the wall thickness of a tubular member comprising: repetitively generating within said member an ultrasonic pulse; directing said pulses in a direction normal to the wall of the member; detecting the returning echoes of said pulses; measuring time period between the echoes from inner and outer walls of the member; and accumulating said measured time periods in a series of counter memories, each of said counter memories accumulating the time periods falling within preset limits.
Claim 2
Independent Claim
79 words
A method for measuring the wall thickness of a tubular member comprising: repetitively generating within said member an ultrasonic pulse; directing said pulses in a direction normal to the wall of the member; detecting the returning echoes of said pulses; measuring time period between the echoes from inner and outer walls of the member; and accumulating said measured time periods in a series of counter memories, each of said counter memories accumulating the time periods falling within preset limits.
Claim 3
Dependent Claim
24 words
The method of claim 1 in which the preset limits of each counter memory corresponds to selected ranges of wall thickness of the member.
Claim 4
Independent Claim
218 words
An apparatus for measuring the wall thickness of a tubular member comprising: an ultrasonic transducer; a transceiver, said transceiver being coupled to said transducer to energize said transducer to produce an ultrasonic pulse and receive any returning echoes; housing means for said transducer, said housing means being adaptable for supporting said transducer within the tubular member to direct a beam of ultrasonic energy along the axis of the tubular member; an acoustical mirror, said mirror being rotatably mounted on said housing for rotation about the axis of the tubular member and having a reflecting surface inclined at an angle to said axis to direct the ultrasonic energy towards the wall of the tubular member; rotating means, said rotating means being coupled to said mirror; a water flow directing means, said water flow directing means being mounted on said housing to produce a water coupling between said transducer, said mirror and the tubular member; elapsed time measuring means, said time measuring means being coupled to said transceiver and disposed to measure the time between the echoes from the inner and outer walls of the tubular member; and accumulating means, said accumulating means being coupled to said elapsed time measuring means to accumulate the measured times that fall within one of a series of predetermined maximum and minimum time periods.
Claim 5
Independent Claim
218 words
An apparatus for measuring the wall thickness of a tubular member comprising: an ultrasonic transducer; a transceiver, said transceiver being coupled to said transducer to energize said transducer to produce an ultrasonic pulse and receive any returning echoes; housing means for said transducer, said housing means being adaptable for supporting said transducer within the tubular member to direct a beam of ultrasonic energy along the axis of the tubular member; an acoustical mirror, said mirror being rotatably mounted on said housing for rotation about the axis of the tubular member and having a reflecting surface inclined at an angle to said axis to direct the ultrasonic energy towards the wall of the tubular member; rotating means, said rotating means being coupled to said mirror; a water flow directing means, said water flow directing means being mounted on said housing to produce a water coupling between said transducer, said mirror and the tubular member; elapsed time measuring means, said time measuring means being coupled to said transceiver and disposed to measure the time between the echoes from the inner and outer walls of the tubular member; and accumulating means, said accumulating means being coupled to said elapsed time measuring means to accumulate the measured times that fall within one of a series of predetermined maximum and minimum time periods.
Claim 6
Dependent Claim
25 words
The apparatus of claim 3 in which said accumulating means comprises a plurality of counter memories, one counter memory being assigned to each time period.
Claim 7
Dependent Claim
88 words
The apparatus of claim 3 in which said elapsed time measuring means comprises a gate means coupled to said transceiver, said gate means being opened by the receiving of the first echo and closed by the receiving of the second echo to generate a pulse; a clock means for generating a series of clock pulses; a digital counting means, said gate means being coupled to both said clock means and said counting means to supply clock pulses to said counting means for the duration of said gate pulse.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-22 | 1980-08-23 | 1981-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-22 | 1984-08-23 | 1985-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-22 | 1988-08-23 | 1989-02-22 | $7700.00 | Window Closed / Lapsed |