CN105716528A - Oil pipe thread size parameter detection method and device - Google Patents
Oil pipe thread size parameter detection method and device Download PDFInfo
- Publication number
- CN105716528A CN105716528A CN201610300946.9A CN201610300946A CN105716528A CN 105716528 A CN105716528 A CN 105716528A CN 201610300946 A CN201610300946 A CN 201610300946A CN 105716528 A CN105716528 A CN 105716528A
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- light source
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/08—Measuring arrangements characterised by the use of optical techniques for measuring diameters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/14—Measuring arrangements characterised by the use of optical techniques for measuring distance or clearance between spaced objects or spaced apertures
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/2425—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures of screw-threads
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/26—Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention relates to an oil pipe thread size parameter detection method and device. A collimated light source is used for lighting, a bi-telecentric lens and an area array CCD digital camera are used for acquiring an upper section image and a lower section image of the oil pipe thread; image processing software is used for extracting outline sub-pixel edge, and computing geometric parameters of the upper section image and the lower section image. The detection device of the invention is mainly composed of a base, an image acquiring component, and a lifting guide rail mechanism and like components; the image acquiring component is composed of a bracket, two collimated LED light sources, two bi-telecentric lenses, two area array CCD digital monochrome camera and the image acquiring and processing software. By virtue of the collimated light source and the bi-telecentric lens, the parts shape image can be acquired, the image cannot be distorted along the distance in a certain range, the measurement speed is fast, and the high-precision measurement result is obtained.
Description
Technical field
The invention belongs to machine components detection technique field, relate to digital picture acquisition methods and the equipment of part, can be used for regular screw threads and the detection of other accessory sizes.
Background technology
Oil pipe is the pipeline that former oil and gas has transported from oil-gas Layer earth's surface after having drilled, and makes consumption very big in oil field, and the quality of tubing round thread directly influences the normal production in oil field.But at present in the production process of oil pipe, manual method is commonly used in tubing round thread dimensional measurement, using external thread gauge and cone gauge to coordinate a series of instruments to carry out manual detection, this measuring method inefficiency, artifical influence factor is very big.
How quickly, accurately measure the size of tubing round thread spatial geometric shape, be a current detection technology difficult problem urgently to be resolved hurrily.
Universal threaded measuring instrument is divided into contact and optical laying formula.Contact type measurement instrument realizes the measurement of screw thread by two hemispherics self-centering methods of probe, there is problems of the processing request to probe high, probe easily abrasion in use procedure, probe easily comes off, needing when measuring screw thread to use the supplementary meanss such as three pins, efficiency is low, complex operation.Optical laying formula is mainly through optical instrument measurements such as universal tool-measuring microscopes, and the subject matter existed is by human eye visual sight, and personal error factor is many, automaticity is low, efficiency is low, and long-time use causes people eyestrain, and universal threaded measuring instrument can not on-line measurement.
Summary of the invention
Present invention aims to the deficiency that above-mentioned existing detection method exists, it is proposed to the method and apparatus of a kind of image on-line checking tubing round thread physical dimension, to improve detection efficiency, accuracy of detection, reduce detection equipment cost.
In order to realize foregoing invention purpose, adopt following detection method:
1, use parallel LED illumination light source, doubly telecentric camera lens, area array CCD digital monochrome collected by camera thread segment image；
2, extract profile sub-pixel edge with image processing software；
3, calculate threads geometrical parameters, the parameter such as including the tooth depth of screw thread, pitch, cone angle and diameter.
The detection equipment of the present invention:
Technical scheme: main be made up of base and the image acquisition component that is arranged on base, image acquisition component by the bracket being arranged on base, be fixed on bracket two restraint parallel LED illumination light source, two doubly telecentric camera lenses, two area array CCD digital monochrome cameras and image acquisition and process software forms.
In image acquisition component, parallel LED illumination light source and telecentric lens are coaxially mounted on bracket.Bracket is arranged on base, it is desirable to lens axis is parallel with light source axis, is positioned at screw thread tooth depth part.
Top image acquisition component is arranged on support plate rail plate, and this rail plate is provided with the elevating screw being mated lifting, and tested tubing round thread is placed on processing unit (plant) support, and measurement apparatus camera lens is parallel with hand of thread spiral.
The source of parallel light of described two groups of doubly telecentric camera lenses and correspondence；Upper group of camera lens light source can according to tubing diameter up-down adjustment position；It is connected with camera lens light source bracket.
Image acquisition and the isoparametric calculating process of tooth depth, pitch, cone angle and diameter:
Adjust base, adjust lens location by base, make lens axis be positioned at thread segment immediate vicinity, fix camera position.
Illumination intensity, camera gain and aperture time are set.
The uncalibrated image of shooting known fixed size component, comes the position of calibration for cameras.Uncalibrated image is made up of two, top and the bottom image, and this group image is detected edge line, and under present image coordinate system, two straight lines of setpoint distance edge line half diametral distance are as demarcation.
Gather screw thread gray level image to be measured with camera real-time online, and the measurement image in gatherer process can be intercepted at any time.
With image processing software the screw image intercepted is processed, computing, obtain corresponding geometric parameter, the parameter such as the tooth depth of screw thread, pitch, cone angle and diameter.
Detection method simple in construction, installation cost is low, simple to operate, and error is in 0.003mm.
Beneficial effects of the present invention:
Part parts physical dimension measurement will be offered convenience and measure more accurately by the present invention, is convenient for measuring, and is also more conducive to the accurate processing of machine part.
The major advantage of the present invention:
Adopting source of parallel light, telecentric lens can ensure that the External Shape image collected, and is not distorted with distance within the specific limits.Software measurement image parameter speed is fast.
Image procossing adopts sub-pix calculate, obtain the measurement result of degree of precision.
May be mounted on process equipment, On-line sampling system.
Accompanying drawing explanation
In order to be illustrated more clearly that embodiment of the present invention technical scheme, below the accompanying drawing used required during embodiment is described is briefly described, apparently, accompanying drawing in the following describes is only that the present invention is in order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below the accompanying drawing used required in p-embodiment or description of the prior art is briefly described, for those of ordinary skill in the art, under the premise not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the structural representation of the present invention.
In figure: 1, base, 2, CCD digital monochrome cameras, 3, doubly telecentric camera lens, 4, camera lens light source bracket, 5, rail plate, 6, support riser, 7, elevating screw, 8, parallel LED illumination light source, 9, tested screw thread.
Detailed description of the invention
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is only a part of embodiment of the present invention, rather than whole embodiments.Based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art obtain under not making creative work premise, broadly fall into the scope of protection of the invention.
Embodiment 1
Camera calibration is measured, known profile size component is installed on part processing stations to be measured, adjust correct position, make its lower edges fall within two camera perspectives, shoot its contour images, set camera gain and aperture time, gather image, obtain demarcating upper and lower two the cross section gray-scale image of parts, extract two width image border profiles, calibrate the position relationship between two cameras by contour line relevant position.
Embodiment 2
Screw thread physical dimension is measured: keep each asset location motionless placement screw thread to be measured, gather upper and lower two the interface gray level images of screw thread, extract thread contour edge in image, find the lower edges of thread, calculating the equation of upper edge and place, lower edge straight line, the distance between two straight lines is the tooth depth of screw thread；Finding out a parallel lines between two straight lines, there is intersection point at this straight line and helical gear edge, and the distance often skipping an intersection point is pitch；Utilize the silhouette edge extracted edge and utilize its cone angle of calibrated and calculated and diameter.Each parameter above, or use nominal data, each through geometrical calculation, obtain the physical dimension parameter of thread segment.
The foregoing is only presently preferred embodiments of the present invention, not in order to limit the present invention, all within the spirit and principles in the present invention, any amendment of making, equivalent replacement, improvement etc., should be included within protection scope of the present invention.
Claims (5)
1. a tubing round thread dimensional parameters detection equipment, it is characterised in that:
Including base and be arranged on the image acquisition component on base, described image acquisition component is made up of the bracket being arranged on base, the parallel LED illumination light source being fixed on bracket, doubly telecentric camera lens, area array CCD digital monochrome camera；
In image acquisition component, parallel LED illumination light source and doubly telecentric camera lens are coaxially mounted on bracket；Bracket is arranged on base, it is desirable to lens axis is parallel with light source axis, is positioned at screw thread tooth depth part.
2. a kind of tubing round thread dimensional parameters detection equipment as claimed in claim 1, it is characterised in that:
Top image acquisition component is arranged on support plate rail plate, and this rail plate is provided with the elevating screw being mated lifting, and tested tubing round thread is placed on processing unit (plant) support, and measurement apparatus camera lens is parallel with hand of thread spiral.
3. a kind of tubing round thread dimensional parameters detection equipment as claimed in claim 1, it is characterised in that:
The source of parallel light of described two groups of doubly telecentric camera lenses and correspondence；Upper group of camera lens light source can according to tubing diameter up-down adjustment position.
4. the tubing round thread dimensional parameters detection method of the equipment used described in any one of claim 1-3, it is characterised in that the method comprises the steps:
(1) using parallel LED illumination light source, doubly telecentric camera lens, area array CCD digital monochrome collected by camera one fixes known profile size component cross-sectional image；
(2) utilize in (1) and measure fixing outline data, demarcate the relative distance position of two cameras；
(3) by two groups of parallel LED illumination light source, doubly telecentric camera lens, area array CCD digital monochrome camera gathers upper and lower thread contour cross-sectional image respectively；
(4) profile sub-pixel edge is extracted with image processing software；
(5) by the upper and lower cross-sectional image of screw thread and camera relative distance position, its geometric parameter is calculated.
5. method as claimed in claim 4, it is characterised in that:
(1) adjusting base, adjust lens axis position by base, make set below lens axis between lower thread, by elevating screw, adjustment one group of lens axis above is between the screw thread of top；
(2) illumination intensity, camera gain and aperture time are set；
(3) the relative distance location position of uncalibrated image collection and camera is as follows:
After arrangement above is intact, place fixing known profile size component on support so that it is lower edges falls within two camera perspectives, shoots its contour images；
With image processing software the component outline image collected is processed, computing, obtain and demarcate the relative distance position of Current camera；
(4) the detection process of screw image collection to be measured and geometric parameter is as follows:
After above step is carried out, keep current all adjustment and arrange constant, taking off demarcation parts, placing screw thread to be measured, shooting its upper and lower contour images；
With image processing software the thread contour image collected is processed, computing, obtain the corresponding required geometric parameter calculated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610300946.9A CN105716528A (en) | 2016-05-09 | 2016-05-09 | Oil pipe thread size parameter detection method and device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610300946.9A CN105716528A (en) | 2016-05-09 | 2016-05-09 | Oil pipe thread size parameter detection method and device |
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| CN105716528A true CN105716528A (en) | 2016-06-29 |
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| CN201610300946.9A Pending CN105716528A (en) | 2016-05-09 | 2016-05-09 | Oil pipe thread size parameter detection method and device |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108387516A (en) * | 2018-01-25 | 2018-08-10 | 陕西方元预应力机械有限公司 | Threading defects detection device and detection method based on CCD camera image processing technologies |
| CN109307486A (en) * | 2017-07-28 | 2019-02-05 | 北京航天控制仪器研究所 | A kind of coaxality measuring mechanism of screw thread and reference axis |
| CN109506585A (en) * | 2018-10-22 | 2019-03-22 | 江苏理工学院 | It is a kind of based on the petroleum casing pipe size device measured indirectly |
| CN110500953A (en) * | 2019-07-10 | 2019-11-26 | 广东嘉铭智能科技有限公司 | Screw thread R value measurement method, device, computer equipment and storage medium |
| CN111207682A (en) * | 2020-01-15 | 2020-05-29 | 山东大学 | Trapezoidal lead screw parameter automatic measuring device and method based on machine vision |
| CN111316060A (en) * | 2017-11-13 | 2020-06-19 | 奥钢联管柱有限责任两合公司 | Device for optically measuring the external thread profile of a pipe |
| CN112164036A (en) * | 2020-09-15 | 2021-01-01 | 西安交通大学 | Device and method for detecting assembly parameters of steel wire thread insert |
| CN112815884A (en) * | 2020-12-23 | 2021-05-18 | 北京动力机械研究所 | Automatic detection method for measuring effective area of adjusting mechanism |
| CN114727007A (en) * | 2021-05-24 | 2022-07-08 | 云南傲远智能环保科技有限公司 | Wisdom plastic network management on-line measuring camera |
| CN115839670A (en) * | 2022-11-22 | 2023-03-24 | 哈尔滨工业大学 | Large-scale high-speed rotation equipment rotor spherical surface profile measuring device based on multi-dimensional backlight imaging |
| CN116295019A (en) * | 2023-05-22 | 2023-06-23 | 中国石油大学(华东) | Automatic detection device for pipe threads of pipe |
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| KR100817656B1 (en) * | 2005-03-15 | 2008-03-31 | 오므론 가부시키가이샤 | Image processing method, 3-dimension position measuring method, and image processing device |
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Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109307486A (en) * | 2017-07-28 | 2019-02-05 | 北京航天控制仪器研究所 | A kind of coaxality measuring mechanism of screw thread and reference axis |
| CN111316060A (en) * | 2017-11-13 | 2020-06-19 | 奥钢联管柱有限责任两合公司 | Device for optically measuring the external thread profile of a pipe |
| US11340062B2 (en) | 2017-11-13 | 2022-05-24 | Voestalpine Tubulars Gmbh & Co Kg | Device for optically measuring the external-thread profile of a pipe |
| CN108387516A (en) * | 2018-01-25 | 2018-08-10 | 陕西方元预应力机械有限公司 | Threading defects detection device and detection method based on CCD camera image processing technologies |
| CN109506585A (en) * | 2018-10-22 | 2019-03-22 | 江苏理工学院 | It is a kind of based on the petroleum casing pipe size device measured indirectly |
| CN110500953A (en) * | 2019-07-10 | 2019-11-26 | 广东嘉铭智能科技有限公司 | Screw thread R value measurement method, device, computer equipment and storage medium |
| CN110500953B (en) * | 2019-07-10 | 2021-10-26 | 广东嘉铭智能科技有限公司 | Thread R value measuring method and device, computer equipment and storage medium |
| CN111207682A (en) * | 2020-01-15 | 2020-05-29 | 山东大学 | Trapezoidal lead screw parameter automatic measuring device and method based on machine vision |
| CN112164036A (en) * | 2020-09-15 | 2021-01-01 | 西安交通大学 | Device and method for detecting assembly parameters of steel wire thread insert |
| CN112164036B (en) * | 2020-09-15 | 2022-06-07 | 西安交通大学 | Device and method for detecting assembly parameters of steel wire thread insert |
| CN112815884A (en) * | 2020-12-23 | 2021-05-18 | 北京动力机械研究所 | Automatic detection method for measuring effective area of adjusting mechanism |
| CN114727007A (en) * | 2021-05-24 | 2022-07-08 | 云南傲远智能环保科技有限公司 | Wisdom plastic network management on-line measuring camera |
| CN115839670A (en) * | 2022-11-22 | 2023-03-24 | 哈尔滨工业大学 | Large-scale high-speed rotation equipment rotor spherical surface profile measuring device based on multi-dimensional backlight imaging |
| CN116295019A (en) * | 2023-05-22 | 2023-06-23 | 中国石油大学(华东) | Automatic detection device for pipe threads of pipe |
| CN116295019B (en) * | 2023-05-22 | 2023-08-15 | 中国石油大学(华东) | Automatic detection device for pipe threads of pipe |
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Inventor after: Lei Jie Inventor after: Niu Haijun Inventor after: Mi Guihua Inventor before: Lei Jie Inventor before: Niu Haijun Inventor before: Mi Guihua |
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Application publication date: 20160629 |