CN114353656A - Eddy current measurement curved surface correction method for thickness of coating of workpiece with gradually-changing curvature - Google Patents
Eddy current measurement curved surface correction method for thickness of coating of workpiece with gradually-changing curvature Download PDFInfo
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- CN114353656A CN114353656A CN202210028534.XA CN202210028534A CN114353656A CN 114353656 A CN114353656 A CN 114353656A CN 202210028534 A CN202210028534 A CN 202210028534A CN 114353656 A CN114353656 A CN 114353656A
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- 238000000576 coating method Methods 0.000 title claims abstract description 35
- 239000011248 coating agent Substances 0.000 title claims abstract description 34
- 238000005259 measurement Methods 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000001514 detection method Methods 0.000 claims abstract description 15
- 239000000523 sample Substances 0.000 claims description 22
- 239000007787 solid Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 238000009675 coating thickness measurement Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000003380 propellant Substances 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
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Abstract
The invention relates to an eddy current measurement and correction method for the coating thickness of a continuous variable-curvature workpiece, which comprises the following steps: calibrating M (M is more than or equal to 6) lifting distances of N (N is more than or equal to 6) curvature radius uncoated standard parts in a curvature interval of a variable-curvature workpiece by using a laser eddy current sensor, and obtaining laser measurement values DJ (N, M) and eddy current measurement values DW (N, M) under N multiplied by M conditions, wherein N is 1. M1.. M; the invention improves the automatic detection by combining laser and eddy current, provides an eddy current measurement correction method for a continuous variable curvature workpiece, and overcomes the influence of human factors in calibration.
Description
Technical Field
The invention belongs to the technical field of workpiece coating thickness measurement, and particularly relates to a method for correcting a curved surface of a workpiece with gradually-changed curvature in eddy current measurement of the coating thickness.
Background
In the modern industrial production process, in order to ensure that the surface of a product has certain characteristics of strengthening, heat insulation and the like, one or more layers of coatings with different thicknesses can be formed on the surface of the product, for example, the coating of a solid rocket engine between a metal shell and a propellant becomes an important component of engine charging, and the coating is not only directly related to the internal function of the solid rocket engine, but also is one of the determinants of the service life of the solid rocket engine. In addition, the coating thickness is determined according to the use environment of the component. The excessive thickness of the coating can cause the excessive internal stress of the product, so that the bonding strength of the substrate and the coating is reduced, and the coating is easy to fall off; if the coating is too thin, the surface treatment requirement of the product cannot be met. Therefore, it is very important to accurately measure the thickness of the coating on the surface of the product to be tested.
In actual detection, an enterprise adopts an eddy current coating thickness gauge for the coating of a curved surface workpiece at present, manual contact is needed in measurement, the influence of physical factors such as pressure is easily caused, and meanwhile, automation is difficult to realize due to the need of contact. The detection method which can realize automation in the prior publication is to adopt the combination of laser and eddy current to automatically detect the solid rocket engine (see Chinese patent No. CN 201610268322.3). The eddy current needs to be calibrated in advance when a curved surface workpiece is measured, but calibration cannot be performed on workpieces with gradually changed curvatures under the condition of each curvature radius. The existing literature and related reports do not relate to the problem of correcting the eddy current measurement of the gradual curvature.
Disclosure of Invention
The invention provides a method for correcting an eddy current measurement curved surface of the thickness of a gradually-changing curvature workpiece coating.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for correcting an eddy current measurement curved surface of the thickness of a coating of a workpiece with gradually-changed curvature comprises the following steps:
1) calibrating the lifting distance of a non-coating standard part with a U curvature radius in a curvature interval of a workpiece with gradually changed curvature by adopting a laser eddy current sensor, wherein the number of the lifting distances is V1、V2...Vu...VxU, wherein U1.. U; x is U; the V is1+V2+...Vu...+VxIs 81, and U is more than or equal to 5; can obtain V1+V2+...Vu...+VxUncoated laser measurements DJ (U, v) and uncoated eddy current measurements DW (U, v) in the case where U1.. U; v ═ Vu；VuCalculating a calibrated value DH (u, v) ═ DJ (u, v) -D0 for the total number of the lifting distances at the u-th curvature radius, wherein D0 is the distance between the laser probe and the eddy current probe;
2) fitting algorithm DH (U, v) ═ A + B · R (U) for DH (U, v), R (U), and DW (U, v) at lifting-off distances of U different radii of curvature2·DW(u,v)2+C·R(u)·DW(u,v)2+D·DW(u,v)2+E·R(u)2·DW(u,v)+F·R(u)·DW(u,v)+G·DW(u,v)+H·R(u)2Obtaining all parameters A, B, C, D, E, F, G, H and I of the lifting distance of the U curvature radius, wherein R (U) is the radius value of the U curvature radius in the curvature interval;
3) detecting the designated position of the workpiece with the gradual change curvature of the coating by adopting a laser eddy current sensor, respectively obtaining a laser measured value TJ with the coating and an eddy current measured value TW with the coating, and correcting a formula TH (A + B r) according to the curvature radius r of the detected position and an eddy current curved surface2·TW2+C·r·TW2+D·TW2+E·r2·TW+F·r·TW+G·TW+H·r2+ I.r, obtaining the corrected lift-off value TH measured by the eddy current probe;
4) calculating to obtain the coating thickness TT (D0 + TH-TJ) at the specified position according to the geometric relation;
5) if the overall detection of the workpiece with the gradually-changed curvature is required, the step 3) and the step 4) are circulated aiming at each detection position.
Furthermore, the laser eddy current sensor consists of a laser probe and an eddy current probe, and the laser probe is fixed right above the eddy current probe.
Compared with the prior art, the invention has the following advantages:
the invention improves the automatic detection based on the combination of laser and eddy current, and provides a correction method for the eddy current measurement curved surface of the workpiece with the gradual change curvature, which not only overcomes the influence caused by human factors in calibration during measurement, simplifies a correction model from the aspect, can effectively improve the operation flow efficiency in engineering practice to a certain extent, improves the universality of the gradual change curvature radius, reduces the measurement error and meets the detection requirement of a solid rocket engine.
Drawings
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a schematic diagram illustrating thickness detection of a curved surface workpiece;
FIG. 3 is a schematic diagram of the use of a laser eddy current sensor;
FIG. 4 is a schematic error plot of the eddy current measurement and the true value before being corrected;
FIG. 5 is a schematic diagram of an error between a corrected lift-off value and a true value of eddy current measurement in a gradient curvature interval;
in the figure, a main measuring arm-1, a joint-2, an auxiliary measuring arm-3, a laser eddy current sensor-4, a coating-5, a detection workpiece-6, a laser probe-7, an eddy current probe-8 and a probe moving direction-9.
Detailed Description
In order to further illustrate the technical solution of the present invention, the present invention is further illustrated by the following examples.
As shown in fig. 1 to 3, a method for correcting an eddy current measurement curved surface of a coating thickness of a workpiece with a gradually-changing curvature includes the following steps:
1) calibrating the lifting distance of a non-coating standard part with a U curvature radius in a curvature interval of a workpiece with gradually changed curvature by adopting a laser eddy current sensor, wherein the number of the lifting distances is V1、V2...Vu...VxU, wherein U1.. U; x is U; the V is1+V2+...Vu...+VxIs 81, and U is more than or equal to 5; can obtain V1+V2+...Vu...+VxUncoated laser measurements DJ (U, v) and uncoated eddy current measurements DW (U, v) in the case where U1.. U; v ═ Vu；VuCalculating a calibrated value DH (u, v) ═ DJ (u, v) -D0 for the total number of the lifting distances at the u-th curvature radius, wherein D0 is the distance between the laser probe and the eddy current probe;
2) fitting algorithm DH (U, v) ═ A + B · R (U) for DH (U, v), R (U), and DW (U, v) at lifting-off distances of U different radii of curvature2·DW(u,v)2+C·R(u)·DW(u,v)2+D·DW(u,v)2+E·R(u)2·DW(u,v)+F·R(u)·DW(u,v)+G·DW(u,v)+H·R(u)2Obtaining all parameters A, B, C, D, E, F, G, H and I of the lifting distance of the U curvature radius, wherein R (U) is the radius value of the U curvature radius in the curvature interval;
3) detecting the designated position of the workpiece with the gradual change curvature of the coating by adopting a laser eddy current sensor, respectively obtaining a laser measured value TJ with the coating and an eddy current measured value TW with the coating, and correcting a formula TH (A + B r) according to the curvature radius r of the detected position and an eddy current curved surface2·TW2+C·r·TW2+D·TW2+E·r2·TW+F·r·TW+G·TW+H·r2+ I.r, obtaining the corrected lift-off value TH measured by the eddy current probe;
4) calculating to obtain the coating thickness TT (D0 + TH-TJ) at the specified position according to the geometric relation;
5) if the overall detection of the workpiece with the gradually-changed curvature is required, the step 3) and the step 4) are circulated aiming at each detection position.
In the above embodiment, the laser eddy current sensor is composed of a laser probe and an eddy current probe, and the laser probe is fixed right above the eddy current probe.
As can be seen from fig. 4 and 5, when the workpiece curvature radius section [20,50] is detected, and the eddy current signals at the section designated positions r of 25, 35, and 45 are acquired, the maximum measurement errors before the correction are 0.09mm, 0.07mm, and 0.06mm, respectively, and the maximum measurement error after the correction is 0.024mm by the eddy current measurement curved surface correction method herein, respectively, can be obtained. It can be seen that after improvement, the measurement error of the workpiece with the gradual change curvature is obviously reduced, the detection standard of the workpiece with the gradual change curvature in engineering practice is met, the applicability of the gradual change curvature is improved, and the detection requirement of a solid rocket engine is met.
While there have been shown and described what are at present considered to be the essential features and advantages of the invention, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (2)
1. A method for correcting the eddy current measurement curved surface of the thickness of a gradually-changed curvature workpiece coating is characterized by comprising the following steps of: comprises the following steps:
1) calibrating the lifting distance of a non-coating standard part with a U curvature radius in a curvature interval of a workpiece with gradually changed curvature by adopting a laser eddy current sensor, wherein the number of the lifting distances is V1、V2...Vu...VxWherein u isU1.. U; x is U; the V is1+V2+...Vu...+VxIs 81, and U is more than or equal to 5; can obtain V1+V2+...Vu...+VxUncoated laser measurements DJ (U, v) and uncoated eddy current measurements DW (U, v) in the case where U1.. U; v ═ Vu；VuCalculating a calibrated value DH (u, v) ═ DJ (u, v) -D0 for the total number of the lifting distances at the u-th curvature radius, wherein D0 is the distance between the laser probe and the eddy current probe;
2) fitting algorithm DH (U, v) ═ A + B · R (U) for DH (U, v), R (U), and DW (U, v) at lifting-off distances of U different radii of curvature2·DW(u,v)2+C·R(u)·DW(u,v)2+D·DW(u,v)2+E·R(u)2·DW(u,v)+F·R(u)·DW(u,v)+G·DW(u,v)+H·R(u)2Obtaining all parameters A, B, C, D, E, F, G, H and I of the lifting distance of the U curvature radius, wherein R (U) is the radius value of the U curvature radius in the curvature interval;
3) detecting the designated position of the workpiece with the gradual change curvature of the coating by adopting a laser eddy current sensor, respectively obtaining a laser measured value TJ with the coating and an eddy current measured value TW with the coating, and correcting a formula TH (A + B r) according to the curvature radius r of the detected position and an eddy current curved surface2·TW2+C·r·TW2+D·TW2+E·r2·TW+F·r·TW+G·TW+H·r2+ I.r, obtaining the corrected lift-off value TH measured by the eddy current probe;
4) calculating to obtain the coating thickness TT (D0 + TH-TJ) at the specified position according to the geometric relation;
5) if the overall detection of the workpiece with the gradually-changed curvature is required, the step 3) and the step 4) are circulated aiming at each detection position.
2. The method for correcting the eddy current measurement curved surface of the coating thickness of the workpiece with the gradually-changed curvature according to claim 1, wherein the method comprises the following steps: the laser eddy current sensor consists of a laser probe and an eddy current probe, and the laser probe is fixed right above the eddy current probe.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116202874A (en) * | 2023-05-05 | 2023-06-02 | 青岛宇通管业有限公司 | Drainage pipe flexibility testing method and system |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1230379A (en) * | 1985-06-28 | 1987-12-15 | Northern Telecom Limited | Measuring the thickness of a non-metallic coating on an arcuate metal surface |
| JPH0655614A (en) * | 1992-08-04 | 1994-03-01 | Hitachi Zosen Sangyo Kk | Device and method for measuring thickness of sheet-shaped component |
| CN101614533A (en) * | 2008-06-26 | 2009-12-30 | 中国科学院金属研究所 | A kind of energy accurately measuring thickness of ultrathin workpieces method and instrument |
| CN102538654A (en) * | 2011-12-26 | 2012-07-04 | 中北大学 | Cylindrical part wall thickness auto-measurement device and measurement method |
| CN105806234A (en) * | 2016-04-27 | 2016-07-27 | 中北大学 | Automatic detection device and detection method for thickness of solid rocket engine coating |
| US20210404929A1 (en) * | 2020-06-29 | 2021-12-30 | Illinois Tool Works Inc. | Thickness correction for video extensometer systems and methods |
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1230379A (en) * | 1985-06-28 | 1987-12-15 | Northern Telecom Limited | Measuring the thickness of a non-metallic coating on an arcuate metal surface |
| JPH0655614A (en) * | 1992-08-04 | 1994-03-01 | Hitachi Zosen Sangyo Kk | Device and method for measuring thickness of sheet-shaped component |
| CN101614533A (en) * | 2008-06-26 | 2009-12-30 | 中国科学院金属研究所 | A kind of energy accurately measuring thickness of ultrathin workpieces method and instrument |
| CN102538654A (en) * | 2011-12-26 | 2012-07-04 | 中北大学 | Cylindrical part wall thickness auto-measurement device and measurement method |
| CN105806234A (en) * | 2016-04-27 | 2016-07-27 | 中北大学 | Automatic detection device and detection method for thickness of solid rocket engine coating |
| US20210404929A1 (en) * | 2020-06-29 | 2021-12-30 | Illinois Tool Works Inc. | Thickness correction for video extensometer systems and methods |
Non-Patent Citations (2)
| Title |
|---|
| 杨晓辉等: "基于涡流检测的曲面涂层厚度影响因素分析", 中北大学学报(自然科学版), vol. 36, no. 1, pages 86 - 90 * |
| 陶正瑞;党嘉强;徐锦泱;安庆龙;陈明;王力;任斐;: "曲面基体绝缘涂镀层涡流测厚高精度标定方法", 浙江大学学报(工学版), no. 06, pages 1218 - 1227 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116202874A (en) * | 2023-05-05 | 2023-06-02 | 青岛宇通管业有限公司 | Drainage pipe flexibility testing method and system |
| CN116202874B (en) * | 2023-05-05 | 2023-07-14 | 青岛宇通管业有限公司 | Drainage pipe flexibility testing method and system |
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