Patent US3732726A successfully refreshed from Google Patents.
US3732726A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for determining the internal diameter of pipes
Assignee: Ver Deutsche Metallwerke AG
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Filing: 1970-12-04
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Granted: 1973-05-15
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Expires: 1990-12-04
Abstract
Abstract A method of and an apparatus for measuring the internal diameter of a pipe in which two inductive displacement pickups detect the external diameter of the pipe and an ultrasonic resonance system is employed for detecting the wall thickness, the pipe being axially shifted through the apparatus and being rotated about its axis concurrently. Periodic variation of the signal representing the wall thickness at a frequency equal to the angular velocity of the pipe are suppressed by filter means. The pipe may also be tested at the same time for longitudinal and transverse defects by means of ultrasonic waves.
Inventors
- 👤 F Ferber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:01
CPC Classifications
G; G01; G01B; G01B7/00; G01B7/12; G01B17/00; G01B17/02; G01B7/125; G01B7/13
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
135 words
A method of continuously testing the internal diameter of a pipe, comprising the steps of: automatically and continuously electromagnetically measuring the external diameter of said pipe to produce an electrical-signal output proportional to said external diameter; automatically and continuously measuring the wall thickness of said pipe by ultrasonic resonance from the exterior thereof to produce an electrical-signal output representing said wall thickness, the electromagnetic measuremenT of the pipe and the ultrasonic-resonance measurement of the wall thickness of the pipe being carried out in the same plane perpendicular to the axis of the pipe; axially shifting said pipe concurrently with rotation thereof past said plane at which said pipe is subjected to electromagnetic and ultrasonic measurement and automatically combining said output electronically to yield a further electrical output signal representing the internal diameter of the pipe.
Claim 2
Independent Claim
135 words
A method of continuously testing the internal diameter of a pipe, comprising the steps of: automatically and continuously electromagnetically measuring the external diameter of said pipe to produce an electrical-signal output proportional to said external diameter; automatically and continuously measuring the wall thickness of said pipe by ultrasonic resonance from the exterior thereof to produce an electrical-signal output representing said wall thickness, the electromagnetic measuremenT of the pipe and the ultrasonic-resonance measurement of the wall thickness of the pipe being carried out in the same plane perpendicular to the axis of the pipe; axially shifting said pipe concurrently with rotation thereof past said plane at which said pipe is subjected to electromagnetic and ultrasonic measurement and automatically combining said output electronically to yield a further electrical output signal representing the internal diameter of the pipe.
Claim 3
Independent Claim
145 words
A method of continuously determining the internal diameter of a pipe, comprising the steps of: axially shifting said pipe concurrently with rotation thereof past a measuring station; measuring the external diameter of said pipe electromagnetically to produce an electrical output proportional to its external diameter during pipe rotation; effecting ultrasonic resonance measurement of the wall thickness of said pipe during rotation thereof to produce an electrical output representing said wall thickness, the electromagnetic measurement and the ultrasonic resonance measurement being carried out in the same plane perpendicular to the axis of said pipe, the output representing the wall thickness having a periodic variation proportional to the speed of rotation of said pipe about said axis; filtering such periodic variations from the last-mentioned output; and electrically combining said outputs subsequent to filtering to yield a further electrical output signal representing the internal diameter of said pipe.
Claim 4
Independent Claim
145 words
A method of continuously determining the internal diameter of a pipe, comprising the steps of: axially shifting said pipe concurrently with rotation thereof past a measuring station; measuring the external diameter of said pipe electromagnetically to produce an electrical output proportional to its external diameter during pipe rotation; effecting ultrasonic resonance measurement of the wall thickness of said pipe during rotation thereof to produce an electrical output representing said wall thickness, the electromagnetic measurement and the ultrasonic resonance measurement being carried out in the same plane perpendicular to the axis of said pipe, the output representing the wall thickness having a periodic variation proportional to the speed of rotation of said pipe about said axis; filtering such periodic variations from the last-mentioned output; and electrically combining said outputs subsequent to filtering to yield a further electrical output signal representing the internal diameter of said pipe.
Claim 5
Dependent Claim
50 words
The method defined in claim 2, further comprising the step of comparing the output signal representing the internal diameter with a set point signal representing the desired internal diameter and producing an alarm signal upon a deviation of said output signal from said set point signal beyond a predetermined limit.
Claim 6
Dependent Claim
50 words
The method defined in claim 2, further comprising the step of comparing the output signal representing the internal diameter of said pipe with a set point signal representing desired internal diameter and marking said pipe upon a deviation of said outputs signal from said set signal beyond a predetermined limit.
Claim 7
Dependent Claim
25 words
The method defined in claim 4, further comprising the step of testing said pipe concurrently for longitudinal and transverse defects by means of ultrasonic waves.
Claim 8
Dependent Claim
18 words
The method defined in claim 2 wherein ultrasonic vibrations are transmitted to the pipe through a liquid medium.
Claim 9
Independent Claim
180 words
The system for checking the internal diameter of a pipe, comprising: a pair of diametrically opposed inductive displacement sensors trained upon an external wall of said pipe for positioning an output signal representing the external diameter thereof; an ultrasonic resonance detector coplanar with said inductive displacement sensors for producing an output representing the wall thickness of said pipe; means for combining said outputs to produce a further output signal representing the internal diameter of the pipe; means forming a liquid column between said detector and said pipe for transmitting ultrasonic vibrations between them; the last-mentioned means including a basin for receiving a bath of liquid in contact with said pipe, said detector extending vertically in said basin and said sensors extending substantially horizontally above said bath; means for displacing said pipe longitudinally through said basin while rotating said pipe about its axis, the means for combining said outputs including a summing amplifier; and filter means between said summing amplifier and said detector for rejecting from the output thereof signals with a periodicity proportional to the angular velocity of said pipe.
Claim 10
Independent Claim
180 words
The system for checking the internal diameter of a pipe, comprising: a pair of diametrically opposed inductive displacement sensors trained upon an external wall of said pipe for positioning an output signal representing the external diameter thereof; an ultrasonic resonance detector coplanar with said inductive displacement sensors for producing an output representing the wall thickness of said pipe; means for combining said outputs to produce a further output signal representing the internal diameter of the pipe; means forming a liquid column between said detector and said pipe for transmitting ultrasonic vibrations between them; the last-mentioned means including a basin for receiving a bath of liquid in contact with said pipe, said detector extending vertically in said basin and said sensors extending substantially horizontally above said bath; means for displacing said pipe longitudinally through said basin while rotating said pipe about its axis, the means for combining said outputs including a summing amplifier; and filter means between said summing amplifier and said detector for rejecting from the output thereof signals with a periodicity proportional to the angular velocity of said pipe.
Claim 11
Dependent Claim
29 words
The system defined in claim 7, further comprising recording means for providing a visual indication of said internal diameter and energized by the output signal of said summing amplifier.
Claim 12
Dependent Claim
69 words
The system defined in claim 8, further comprising comparator means energized by said output signal of said summing amplifier, means foR applying a set point signal representing a desired internal diameter to said comparator means, and marking means responsive to said comparator means for applying a marking to the pipe upon deviation of the output signal of said summing amplifier from said set point signal beyond a predetermined level.
Claim 13
Dependent Claim
62 words
The system defined in claim 9, further comprising comparator means energized by said output signal of said summing amplifier, means for applying a set point signal representing a desired internal diameter to said comparator means, and alarming means for providing a sensored output upon deviation of the output signal of said summing amplifier from said set point signal beyond a predetermined level.
Claim 14
Independent Claim
145 words
The system for checking the internal diameter of a pipe, comprising: a pair of diametrically opposed inductive displacement sensors trained upon an external wall of said pipe for producing an output signal representing the external diameter thereof; an ultrasonic resonance detector coplanar with said inductive displacement sensors for producing an output representing the wall thickness of said pipe; means forming a liquid column between said detector and said pipe for transmitting ultrasonic vibrations between them, wherein said last mentioned means is a basin for receiving a bath of liquid in contact with said pipe, said detector extending vertically in said basin and said sensors extending substantially horizontally above said bath; means for combining said outputs to produce a further output signal representing the internal diameter of the pipe; and means for displacing said pipe longitudinally through said basin while rotating said pipe about its axis.
Claim 15
Independent Claim
145 words
The system for checking the internal diameter of a pipe, comprising: a pair of diametrically opposed inductive displacement sensors trained upon an external wall of said pipe for producing an output signal representing the external diameter thereof; an ultrasonic resonance detector coplanar with said inductive displacement sensors for producing an output representing the wall thickness of said pipe; means forming a liquid column between said detector and said pipe for transmitting ultrasonic vibrations between them, wherein said last mentioned means is a basin for receiving a bath of liquid in contact with said pipe, said detector extending vertically in said basin and said sensors extending substantially horizontally above said bath; means for combining said outputs to produce a further output signal representing the internal diameter of the pipe; and means for displacing said pipe longitudinally through said basin while rotating said pipe about its axis.
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) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |