CA1150496A - Measuring device for internal pipe dimensions - Google Patents
Measuring device for internal pipe dimensionsInfo
- Publication number
- CA1150496A CA1150496A CA000355860A CA355860A CA1150496A CA 1150496 A CA1150496 A CA 1150496A CA 000355860 A CA000355860 A CA 000355860A CA 355860 A CA355860 A CA 355860A CA 1150496 A CA1150496 A CA 1150496A
- Authority
- CA
- Canada
- Prior art keywords
- tube
- flexible members
- internal surface
- detecting
- support
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D401/00—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom
- C07D401/02—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom containing two hetero rings
- C07D401/04—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom containing two hetero rings directly linked by a ring-member-to-ring-member bond
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/28—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring contours or curvatures
- G01B7/287—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring contours or curvatures using a plurality of fixed, simultaneously operating transducers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/12—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring diameters
- G01B7/13—Internal diameters
Abstract
MEASURING DEVICE FOR USE WITH TUBULAR PRODUCTS
Abstract of the Disclosure Apparatus for detecting variations in the internal dimensions of a pipe includes a plurality of cantilever members for engaging the internal surface and strain gauges mounted on the cantilever members which are responsive to the flexing of the cantilever members. A
Wheatstone bridge is utilized to measure changes in resistance of the strain gauges and hence the amount of flexing of the cantilevers due to undulations in the internal surface. The apparatus is particularly useful in detecting and measuring dents in tubes of nuclear power plant steam generators caused by corrosion of steel support plates.
Abstract of the Disclosure Apparatus for detecting variations in the internal dimensions of a pipe includes a plurality of cantilever members for engaging the internal surface and strain gauges mounted on the cantilever members which are responsive to the flexing of the cantilever members. A
Wheatstone bridge is utilized to measure changes in resistance of the strain gauges and hence the amount of flexing of the cantilevers due to undulations in the internal surface. The apparatus is particularly useful in detecting and measuring dents in tubes of nuclear power plant steam generators caused by corrosion of steel support plates.
Description
MEASI~RING DRVICE FOR lNTRRNAL PIPE DIMENSIONS
This invention relates generally to measuring apparatus, and more particularly the invention relates to apparatus for detecting variations in the internal dimensions oE a tubular product such as a pipe and the like.
Defects in the internal surfaces of steam generator tubes in nuclear power plants can result in failure of the tubes. More particularly, denting of steam generator tubes due to corrosion of carbon steel support plates occurs over a period of time and must be monitored. Defects such as pits and cracks can be monitored by eddy current sensors which detect variations in conductivity characteristics of the internal surface. However, such sensors are less reliable for measuring denting at support plates because of the complex electromagnetic response created by the steel support plates.
Accordingly, an object of the present invention is an improved apparatus for detecting variations in the internal dimensions of a tube and the like.
Another object of the invention is improved ~eans for monitoring denting of tubes due to corrosion of support plates.
A feature of the invention is the use of flexible members having surface portions for engaging the internal surface of a tubular product and transducer means for sensing flex of the members due to variations of the internal surfaceP
Another feature of the invention is a housing having a plurality of spring means for engaging the internal surface of a pipe and maintaining the apparatus generally in line with the center line of the pipe.
, ~-2-In a preferred emhodiment the apparatus of the present invention comprises support means of suitable dimensions for moving through a tube, the suppport means inc]uding an outer housing and a plurality of spring means for engaging the internal surface and maintaining the outer housing generally in line with the center line of the tube; a plurality of flexible members extending from the support means and having a surface portion for engaging the internal surface of the tube; transducer means mounted on each of the flexible members for sensing flex of the member; and eddy current detention means for detecting the presence of tube support structures externally of and adJacent the tube.
In the drawing, Figure 1 is a p~rspective view of measuring apparatus in accordance with one embodiment of the invention.
Figure 2 is a section view of the apparatus of Figure 1.
FigurP 3 is an electrical schematic illustrating the function of the flexible member in the apparatus of Figure 1.
Figure 4 is a plan view of a portion of the apparatus of Figure 1 with the outer housing removed.
Referring now to the drawings, Figure 1 is a perspective view of measuring apparatus in accordance with one embodiment of the invention. The apparatus includes a housing 10 of suitable material such as aluminum or steel having a plurality of springlike feelers 12 and 14 at either end of the housing. Feelers 12 and 14 are preferably formed of the housing material and are positioned about housing 10 to engage the inner surface of a tubular product and thereby maintain the apparatus positioned on the center line of the tubular product. In a preferred embodiment the feelers 12, 14 are positioned at 45 intervals about the circumference of housing 10 .
At the forward end of housing 10 is an eddy current locating coil 16 which is wound on a non-metallic bobbin 18 of wood or other suitable material and which projects fro~ support housing 10.
.. .
~ J ~ ~ 6 -2a-At the other end of the apparatus is a flexible coupling 20 which couples the apparatus to drive means such as a nylon tube 22 for moving the apparatus through the tubular product being inspected. Coupling 20 and tube 22 include a cavlty through which electrical wiring is provided.
Projecting through openings 24 in housing 10 intermediate the .. -, ~.
_3_ ~ $ ~4Ji~ ~ ~
centering springs 12 and 14 are a plurality of membe~s 26 which engage the inner surface of the tubular product being inspected.
As will be described further hereinbelow, the members 26 comprise surface portions of flexible members such as cantilevers which flex S in response to undulations such as dents in the inner surface of the tubular product being inspected.
Figure 2 is a section view of the apparatus of Figure 1 which further illustrates the components of the measuning apparatus and the mounting of components within housing 10. Bobbin 18 which supports the eddy current locating coil 16 extends from one end of the housing 10 and is of suitable configuration to accommodate the flexing of centering spring 14. Members 26 extend through windows 24 in housing 10 and are provided on the flexing end of cantilevers 28. The other ends of cantilevers 28 are affixed to or comprise part of support member 30 which is mounted within housing 10. Support member 30 receives the flexible coupler 20. The cantilevers are made of suitable material such as steel which has the requisite resilience. Mounted on cantilever 28 near the support ends are transducer means such as strain gauges 32 which change in resistive value upon the flex1ng of cantilevers 28. Support member 30 is of suitable configuration to accommodate the flexing of centering spring 12.
Figure 3 is an electrical schematic illustrating the function of the cantilever 28 and strain gauge 32 in a WheatstGne bridge type of readout circuit. The strain gauge 32 comprises two resistors in the Wheatstone bridge along with fixed resistors 34 and 36. A suitable DC voltage source 38 is provided 'or energi~ing the bridge. As the measuring apparatus is moved through the tubular product under inspection, the eddy current locating coil will give an indication of an approaching steel support plate for which the Wheats-tone bridge readout indicates the presence of denting. Thus, as the cantilever 28 flexes in response to the surface portion 26 engaging undulations in the inner surface of a tubular product, the readout from the Wheatstone bridge will likewise vary, thereby giving an indication of the inner surface undulation.
Figure 4 is a plan view of the apparatus of Figures 1 and 2 ~5~4~
with the outer housing removed to further illustrate the cantilever members 28 with the strain gauges 32 mounted thereon. Conductive wires 40 interconnect the strain gauges 32 to the external Wheatstone bridge readout through support 30 and the flexible coupling.
Apparatus in accordance with the present invention has proved to be particularly useful in inspecting tubes in steam generators in nuclear power plants and particularly the presence of dents in the tubes caused by corrosion of steel support plates which are nDt readily measured by prior art eddy current means.
While the invention has been described with reference to one embodiment and one application, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications and applications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims.
This invention relates generally to measuring apparatus, and more particularly the invention relates to apparatus for detecting variations in the internal dimensions oE a tubular product such as a pipe and the like.
Defects in the internal surfaces of steam generator tubes in nuclear power plants can result in failure of the tubes. More particularly, denting of steam generator tubes due to corrosion of carbon steel support plates occurs over a period of time and must be monitored. Defects such as pits and cracks can be monitored by eddy current sensors which detect variations in conductivity characteristics of the internal surface. However, such sensors are less reliable for measuring denting at support plates because of the complex electromagnetic response created by the steel support plates.
Accordingly, an object of the present invention is an improved apparatus for detecting variations in the internal dimensions of a tube and the like.
Another object of the invention is improved ~eans for monitoring denting of tubes due to corrosion of support plates.
A feature of the invention is the use of flexible members having surface portions for engaging the internal surface of a tubular product and transducer means for sensing flex of the members due to variations of the internal surfaceP
Another feature of the invention is a housing having a plurality of spring means for engaging the internal surface of a pipe and maintaining the apparatus generally in line with the center line of the pipe.
, ~-2-In a preferred emhodiment the apparatus of the present invention comprises support means of suitable dimensions for moving through a tube, the suppport means inc]uding an outer housing and a plurality of spring means for engaging the internal surface and maintaining the outer housing generally in line with the center line of the tube; a plurality of flexible members extending from the support means and having a surface portion for engaging the internal surface of the tube; transducer means mounted on each of the flexible members for sensing flex of the member; and eddy current detention means for detecting the presence of tube support structures externally of and adJacent the tube.
In the drawing, Figure 1 is a p~rspective view of measuring apparatus in accordance with one embodiment of the invention.
Figure 2 is a section view of the apparatus of Figure 1.
FigurP 3 is an electrical schematic illustrating the function of the flexible member in the apparatus of Figure 1.
Figure 4 is a plan view of a portion of the apparatus of Figure 1 with the outer housing removed.
Referring now to the drawings, Figure 1 is a perspective view of measuring apparatus in accordance with one embodiment of the invention. The apparatus includes a housing 10 of suitable material such as aluminum or steel having a plurality of springlike feelers 12 and 14 at either end of the housing. Feelers 12 and 14 are preferably formed of the housing material and are positioned about housing 10 to engage the inner surface of a tubular product and thereby maintain the apparatus positioned on the center line of the tubular product. In a preferred embodiment the feelers 12, 14 are positioned at 45 intervals about the circumference of housing 10 .
At the forward end of housing 10 is an eddy current locating coil 16 which is wound on a non-metallic bobbin 18 of wood or other suitable material and which projects fro~ support housing 10.
.. .
~ J ~ ~ 6 -2a-At the other end of the apparatus is a flexible coupling 20 which couples the apparatus to drive means such as a nylon tube 22 for moving the apparatus through the tubular product being inspected. Coupling 20 and tube 22 include a cavlty through which electrical wiring is provided.
Projecting through openings 24 in housing 10 intermediate the .. -, ~.
_3_ ~ $ ~4Ji~ ~ ~
centering springs 12 and 14 are a plurality of membe~s 26 which engage the inner surface of the tubular product being inspected.
As will be described further hereinbelow, the members 26 comprise surface portions of flexible members such as cantilevers which flex S in response to undulations such as dents in the inner surface of the tubular product being inspected.
Figure 2 is a section view of the apparatus of Figure 1 which further illustrates the components of the measuning apparatus and the mounting of components within housing 10. Bobbin 18 which supports the eddy current locating coil 16 extends from one end of the housing 10 and is of suitable configuration to accommodate the flexing of centering spring 14. Members 26 extend through windows 24 in housing 10 and are provided on the flexing end of cantilevers 28. The other ends of cantilevers 28 are affixed to or comprise part of support member 30 which is mounted within housing 10. Support member 30 receives the flexible coupler 20. The cantilevers are made of suitable material such as steel which has the requisite resilience. Mounted on cantilever 28 near the support ends are transducer means such as strain gauges 32 which change in resistive value upon the flex1ng of cantilevers 28. Support member 30 is of suitable configuration to accommodate the flexing of centering spring 12.
Figure 3 is an electrical schematic illustrating the function of the cantilever 28 and strain gauge 32 in a WheatstGne bridge type of readout circuit. The strain gauge 32 comprises two resistors in the Wheatstone bridge along with fixed resistors 34 and 36. A suitable DC voltage source 38 is provided 'or energi~ing the bridge. As the measuring apparatus is moved through the tubular product under inspection, the eddy current locating coil will give an indication of an approaching steel support plate for which the Wheats-tone bridge readout indicates the presence of denting. Thus, as the cantilever 28 flexes in response to the surface portion 26 engaging undulations in the inner surface of a tubular product, the readout from the Wheatstone bridge will likewise vary, thereby giving an indication of the inner surface undulation.
Figure 4 is a plan view of the apparatus of Figures 1 and 2 ~5~4~
with the outer housing removed to further illustrate the cantilever members 28 with the strain gauges 32 mounted thereon. Conductive wires 40 interconnect the strain gauges 32 to the external Wheatstone bridge readout through support 30 and the flexible coupling.
Apparatus in accordance with the present invention has proved to be particularly useful in inspecting tubes in steam generators in nuclear power plants and particularly the presence of dents in the tubes caused by corrosion of steel support plates which are nDt readily measured by prior art eddy current means.
While the invention has been described with reference to one embodiment and one application, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications and applications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims.
Claims (7)
1. Apparatus for detecting denting in the internal surface of a tube due to corrosion of support plates comprising support means of suitable dimensions for moving through said tube, said support means including an outer housing and a plurality of spring means for engaging said internal surface and maintaining said outer housing generally in line with the center line of said tube; a plurality of flexible members extended from said suuport means, each of said flexible members having a surface portion for engaging said internal surface;
transducer means mounted on each of said flexible members for sensing flex of said member; and eddy current detection means for detecting the presence of tube support structures.
transducer means mounted on each of said flexible members for sensing flex of said member; and eddy current detection means for detecting the presence of tube support structures.
2. Apparatus as defined by Claim 1 wherein said housing includes a plurality of openings and said surface portions of said flexible members extend through said openings.
3. Apparatus as defined by Claims 1 or 2 wherein each of said flexible members comprises a cantilever having an extended end and a supported end, said surface portion being near said extended end and said transducer means being mounted to said member near said supported end.
4. Apparatus as defined by Claim 3 wherein said transducer means comprises a strain gauge,
5. Apparatus as defined by Claim 4 wherein said transducer means further includes Wheatstone bridge means for detecting changes in said strain gauge as said cantilever is flexed.
6. Apparatus as defined by Claim 5 and including means for moving said support means through said tube.
7. Apparatus as defined by Claim 1 wherein said transducer means comprises a strain gauge which has an electrical resistance which changes in response to flexing of said member and Wheatstone bridge means for detecting changes in said electrical resistance.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US81,657 | 1979-10-04 | ||
| US06/081,657 US4301677A (en) | 1979-10-04 | 1979-10-04 | Measuring device for use with tubular products |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1150496A true CA1150496A (en) | 1983-07-26 |
Family
ID=22165544
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000355860A Expired CA1150496A (en) | 1979-10-04 | 1980-07-10 | Measuring device for internal pipe dimensions |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4301677A (en) |
| JP (1) | JPS5660305A (en) |
| KR (1) | KR830001925B1 (en) |
| CA (1) | CA1150496A (en) |
| DE (1) | DE3032424C2 (en) |
Families Citing this family (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CS209709B1 (en) * | 1979-11-23 | 1981-12-31 | Jan Jandera | Apparatus for internal inspection of long-distance pipelines |
| US4341113A (en) * | 1980-08-08 | 1982-07-27 | The Babcock & Wilcox Company | Inspection system for heat exchanger tubes |
| DE3231137A1 (en) * | 1982-08-21 | 1984-02-23 | Hermann 4450 Lingen Rosen | Measuring pig |
| US4495810A (en) * | 1983-04-20 | 1985-01-29 | General Electric Company | Probe mounting system |
| FR2553877B1 (en) * | 1983-10-19 | 1985-12-27 | Commissariat Energie Atomique | PROBE FOR MEASURING THE INTERNAL DIAMETER OF A TUBE AND DEVICE FOR INTRODUCING THE SAME INTO THE TUBE |
| JPS60196614A (en) * | 1984-03-21 | 1985-10-05 | Sumitomo Heavy Ind Ltd | Apparatus for measuring thickness of pipe |
| US4541278A (en) * | 1984-04-23 | 1985-09-17 | Union Oil Company Of California | Pipeline corrosion sensing device and method |
| JPS62163716U (en) * | 1986-04-08 | 1987-10-17 | ||
| DE3722254A1 (en) * | 1987-07-06 | 1989-01-19 | Schwenk Oskar Gmbh & Co Kg | Centring and aligning device for bore meters |
| ES2029505T3 (en) * | 1987-10-09 | 1992-08-16 | Marposs Societa' Per Azioni | APPARATUS TO CHECK THE LINEAR DIMENSIONS OF THE PARTS. |
| US4910877A (en) * | 1988-07-18 | 1990-03-27 | The United States Of America As Represented By The United States Department Of Energy | Tube curvature measuring probe and method |
| US6248083B1 (en) | 1997-03-25 | 2001-06-19 | Radi Medical Systems Ab | Device for pressure measurements |
| JP3679419B2 (en) * | 1997-03-25 | 2005-08-03 | ラディ・メディカル・システムズ・アクチェボラーグ | Guide wire assembly and system using the same |
| US5833605A (en) * | 1997-03-28 | 1998-11-10 | Shah; Ajit | Apparatus for vascular mapping and methods of use |
| WO2001070437A2 (en) * | 2000-03-20 | 2001-09-27 | Cognitens, Ltd. | Self-centering accessories for an industrial environment |
| GB0031216D0 (en) * | 2000-12-20 | 2001-01-31 | Aea Technology Plc | Measurement of stress |
| US20060106321A1 (en) * | 2003-01-16 | 2006-05-18 | Galil Medical Ltd. | Device, system, and method for detecting, localizing, and characterizing plaque-induced stenosis of a blood vessel |
| WO2004062525A2 (en) * | 2003-01-16 | 2004-07-29 | Galil Medical Ltd. | Device, system, and method for detecting and localizing obstruction within a blood vessel |
| US20060042363A1 (en) * | 2004-08-27 | 2006-03-02 | Honeywell International, Inc. | Method for detecting corrosion in industrial process equipment |
| DE602005001672T2 (en) * | 2004-09-20 | 2008-06-05 | Weatherford/Lamb, Inc., Houston | Diameter measuring devices |
| DE102005037433A1 (en) * | 2005-08-04 | 2007-02-08 | Rheinmetall Waffe Munition Gmbh | Measuring device for measuring an inner diameter, in particular in a weapon barrel |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2656613A (en) * | 1948-04-17 | 1953-10-27 | Eastman Oil Well Survey Co | Apparatus for calipering well bores |
| US3010212A (en) * | 1957-04-18 | 1961-11-28 | John C Kinley | Calipering tools |
| US2915830A (en) * | 1958-05-21 | 1959-12-08 | Tuboscope Company | Tubing caliper |
| US3024651A (en) * | 1959-01-12 | 1962-03-13 | Continental Oil Co | Method and apparatus for the testing of a tubular member |
| US3628029A (en) * | 1968-07-15 | 1971-12-14 | Schlumberger Technology Corp | Apparatus for inspecting tubular goods |
| US3939570A (en) * | 1974-06-20 | 1976-02-24 | Loftus William F | Apparatus for and process of determining overstress in pipe piles |
| US4109386A (en) * | 1975-05-29 | 1978-08-29 | John C. Kinley | Signal-producing pipe caliper |
| US4235020A (en) * | 1979-05-02 | 1980-11-25 | The Babcock & Wilcox Company | Inspection system for heat exchanger tubes |
-
1979
- 1979-10-04 US US06/081,657 patent/US4301677A/en not_active Expired - Lifetime
-
1980
- 1980-07-10 CA CA000355860A patent/CA1150496A/en not_active Expired
- 1980-08-28 DE DE3032424A patent/DE3032424C2/en not_active Expired
- 1980-10-02 JP JP13683580A patent/JPS5660305A/en active Pending
- 1980-10-04 KR KR1019800003821A patent/KR830001925B1/en active
Also Published As
| Publication number | Publication date |
|---|---|
| DE3032424C2 (en) | 1986-01-09 |
| KR830004597A (en) | 1983-07-16 |
| KR830001925B1 (en) | 1983-09-23 |
| DE3032424A1 (en) | 1981-04-09 |
| US4301677A (en) | 1981-11-24 |
| JPS5660305A (en) | 1981-05-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |