THREADED ELEMENT INSPECTION DEVICE AND CORRESPONDING INSPECTION METHOD
Patent Information
- Authority / Receiving Office
- MX · MX
- Patent Type
- Patents
- Current Assignee / Owner
- VALLOUREC MANNESMANN OIL & GAS FRANCE
- Filing Date
- 2025-05-28
- Publication Date
- 2026-06-12
Smart Images
Figure MX435209B0
Abstract
Description
Description Title of the invention: THREADED ELEMENT INSPECTION DEVICE AND CORRESPONDING INSPECTION METHOD Technical field [1]The present invention relates to a device and a method for measuring the thread shape for a threaded element, more particularly for measuring the thread shape of elements such as a threaded joint for an oil well, carbon dioxide or hydrogen storage, or geothermal well pipe. [2]The thread form measurement determines a thread form profile in the axial screwing direction of the threaded element, and the thread elements are measured based on the thread form profile. In the case of, for example, an oil well pipe thread, the thread elements include the following: A threaded area, which is a portion of surface of a threaded element axially delimited by a first end of thread on one side and on the other side by a second end of this thread. [3]Threaded elements have threaded ends. These threaded ends are complementary, allowing the connection of a male tubular component ("Pin" in English) and a female tubular component ("Box" in English) to each other. There is therefore a male threaded end and a female threaded end. A threaded area may comprise so-called perfect threads or so-called imperfect threads, an imperfect thread having a section corresponding to an incomplete section of a corresponding perfect thread, for example over a reduced height. [4] A thread is a set of threads of a part, male or female, generated by a geometric profile moving along a surface following a helical movement. [5]A thread comprises, seen in a sectional representation, a succession of teeth or threads regularly spaced from each other. Thus, in a sectional representation, the term "tooth" means a slotted portion i extending from the base of an engaging flank to the base of a supporting flank, said engaging flank and said supporting flank being joined by a crest. [6] Within a threaded end, a portion of male or female thread seen in cross-section has a straight line segment connecting mid-heights of flanks of threads carrying consecutive threads, said segment forming an angle with the axis of the threaded end. If this angle is zero, the portion of thread is said to be cylindrical. If the angle is non-zero, the portion of thread is said to be conical. The angle can be expressed in degrees, radiants, percentage. The thread angle is equal to twice the angle formed between said straight line segment and the axis of the threaded end, or the thread angle is equal to the angle at the apex of the cone formed by the straight line segment as a generator rotating around the axis of the threaded end. [7]A thread can be cylindrical, that is, have a generatrix parallel to the axis of the threaded end, or a thread can be conical, that is, have a generatrix forming a non-zero angle with respect to the axis of the threaded end. [8]A net consists of two sides, an engagement side and a load side, a net base and a net top. [9]Stabbing flanks are the thread surfaces that are likely to come into contact when the threads of male and female threaded components are engaged with each other. They therefore correspond to the flanks directed towards the free end of the tubular component in question.
[0010] Loading flanks are the thread surfaces that are likely to come into contact when a threaded joint is subjected to axial tensile forces. They therefore correspond to the flanks facing away from the free end of the tubular component in question.
[0011] Positive or negative angle(s): By convention, within the framework of the invention, the anti-trigonometric direction will be used, which is also the clockwise direction. Thus, a positive angle goes in the clockwise direction and conversely a negative angle goes in the counterclockwise direction.
[0012] Machining a tube to produce its thread implies the existence of a thread pitch. The concept of thread pitch must be understood in light of the ISO 5408:2009 standard, which covers the definition of threads. The thread pitch corresponds to the axial distance, on one revolution, between two successive points such as two successive summits or two successive bottoms of a thread, said distance being called "P". The thread pitch must be controlled in order to allow screwing between the male thread and the corresponding female thread for assembly and use of a joint. Technological background
[0013] Conventional techniques for measuring the thread shape of threaded elements are known, based for example on tangential illumination of the thread and image capture by an optical sensor facing the light source so as to generate a two-dimensional image. There are variations on the orientation of the light emission, the use of mirrors, but these methods have the disadvantage of lacking precision and being only suitable for a limited number of types of connections. Indeed, as soon as a thread flank has a negative angle, it is impossible to project its complete profile, making direct measurement impossible.
[0014] Furthermore, even in a case where the thread is irradiated with parallel light in the tangential direction of the helix of the thread, the parallel light path is linear and not helical, and therefore, the thread shape profile captured by the parallel light is different from the actual profile which is helical thereto, with the interference of the surfaces adjacent to an intended slice.
[0015] Furthermore, the device according to the invention is transportable. Summary
[0016] The invention is based on the use of two optical sensors with distinct capture directions, and the possibility of combining the measurement data from the two sensors to reconstruct a measured thread shape, thus reducing control cycle times and digitizing a profile which can then be validated.
[0017] According to one embodiment, the invention provides a device for dimensional measuring of a threaded element comprising a chassis, the chassis comprising a first line laser sensor having a first optical measurement direction and a second line laser sensor having a second optical measurement direction, said second optical measurement direction forming a non-zero angle with the first optical measurement direction in a plane containing the first optical measurement direction, the first line laser sensor and the second line laser sensor being movably mounted on the chassis and having at least one measurement path for carrying out geometric data acquisitions of the threaded element passing through a calibration template and being able to pass through a portion of the threaded element, the device comprising an encoder arranged to determine a position of the first line laser sensors and a position of the second line laser sensors along a main axis and electronics arranged to construct a first partial profile from the first line laser sensor and a second partial profile from the second line laser sensor,the electronics being arranged to construct a complete profile from the first partial profile and the second partial profile as a function of the respective positions of the first line laser sensor and the second line laser sensor and as a function of at least one measurement carried out on the calibration template.,
[0018] It is thus possible to propose a device making it possible to test and measure one end of a threaded element with great precision, while being able to carry out measurements in poorly controlled environments, the positioning of the threaded element relative to the device being mechanically controlled and the sources of errors linked to the positioning being compensated for each measurement operation by calibration means integrated into the operation.
[0019] According to embodiments, such a device may comprise one or more of the following features.
[0020] According to one embodiment, the angle is between 30° and 70°, preferably between 40° and 60°. This makes it possible to measure a wide variety of threads with a hook-type profile or a dovetail-type profile.
[0021] According to one embodiment, the first line laser sensor and the second line laser sensor are mounted in translation on the chassis. Thus, the trajectory of the sensors relative to the part to be measured is simple and it is possible to compensate for an error in the positioning misalignment of the threaded element relative to the device.
[0022] According to one embodiment, the calibration template comprises surfaces delimiting predetermined reference lengths. This makes it possible to provide dimensional benchmarks for the calibration process during a measuring operation.
[0023] According to one embodiment, the calibration jig comprises a bearing face arranged to contact an end face of the threaded element to be measured. This makes it possible to minimize positioning errors of the threaded element relative to the device and to simplify the calibration procedure.
[0024] According to one embodiment, the device comprises a positioning wedge arranged to be able to rest on the thread crests of the threaded element. This makes it possible to simplify and make more reliable the positioning of the device on the threaded element.
[0025] According to one embodiment, the positioning wedge comprises a frustoconical insertion surface having a frustoconical insertion surface axis and being capable of being in contact with the thread crests of the threaded element. This makes it possible to adapt the positioning wedge and the device to threaded elements having a tapered thread.
[0026] According to one aspect, the bearing face is perpendicular to the axis of the frustoconical insertion surface of the positioning wedge.
[0027] According to one embodiment, the calibration template comprises an engagement flank reference surface, a load flank reference surface, an axial length reference surface, a radial length reference surface. This makes it possible to define length references for the calibration which correspond to the nominal characteristics of the threaded element to be measured, and to improve the measurement accuracy.
[0028] According to one embodiment, the calibration template comprises a longitudinal reference extension defining a reference length Dr and the electronics are arranged to determine a measurement trajectory correction factor linked to the trajectory of the first and second line laser sensors. This makes it possible to correct the measured values according to an error in the positioning misalignment of the threaded element relative to the device.
[0029] According to one embodiment, the electronics are arranged to compare a digital thread profile comprising minimum and maximum dimensions with the complete profile and the electronics are configured to generate a result of thread conformity. This provides the user with a result of the conformity of the threaded element.
[0030] In one aspect, the electronics are arranged to perform dimensional measurements of surfaces of the end of the threaded member.
[0031] The invention is also a method of dimensional measurement of one end of a threaded element comprising the steps of: - mount the measuring device as above on the threaded element - perform data acquisition with the first line laser sensor and the second line laser sensor on the measuring template - determine measurement correction factors and store them in an electronic memory -perform a second data acquisition on the end of the threaded element with the first line laser sensor and the second line laser sensor - generate a first partial profile from a first data set from the second data acquisition by the first line laser sensor - generate a second partial profile from a second data set from the second data acquisition by the second line laser sensor - generate a complete profile from the first partial profile, the second partial profile and the measurement correction factors.
[0032] The method allows to validate and measure a threaded element with regard to its dimensional characteristics with simple operations and with very high precision. Brief description of the figures
[0033] The invention will be better understood, and other objects, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes, with reference to the accompanying drawings. [fig. 1] Figure 1 is a perspective view of the device in measurement situation on a threaded element. [fig. 2] Figure 2 is a perspective view of a calibration template according to the invention. [fig. 3] Figure 3 is a perspective view of a positioning wedge according to the invention. [fig. 4] Figure 4 is a schematic sectional view of an alternative embodiment of the device of figure 1 in the context of a female-type threaded element. Description of the embodiments
[0034] The measuring device 1 according to the invention as visible in figure 1 comprises a frame 2 comprising a table 10, substantially rectangular on which is mounted on a first side a handle 13 which an operator can operate to push the table towards a threaded element 6 or to pull the device from the threaded element 6. The table 10 comprises on a side opposite the first side at least one jack 12 connected to a positioning wedge 8. In the illustrated embodiment, the device comprises two jacks 12.
[0035] The positioning wedge 8 isolated in Figure 3 comprises an insertion surface 9 arranged to be in contact with thread crests of a threaded element 6. In the illustrated embodiment, the threaded element comprises a male thread having a taper. Accordingly, the positioning wedge 8 comprises a frustoconical insertion surface 9 with a taper corresponding substantially to the taper of the thread, the frustoconical insertion surface 9 being turned inwards so as to contact the crests of the male threads of the threaded element 6 which are turned outwards. This frustoconical insertion surface 9 makes it possible to align the device with the axis of the thread. The frustoconical insertion surface 9 comprises a larger internal diameter and a smaller internal diameter such that the frustoconical insertion surface 9 comes to be positioned on perfect threads of the threaded element 6.Indeed, the truncated insertion surface 9 must rest on perfect threads of the threaded element 6. It will be understood that the positioning wedge 8 is sized according to the connection model whose threading it is desired to control, more particularly the taper of the threading of the connection model. There is therefore a positioning wedge adapted to a conical connection for example of the VAM© TOP 7-5 / 8 type, another positioning wedge adapted to a conical connection of the VAM© 21 5-3 / 4 type, or even a cylindrical connection of the API type, etc. . .A positioning wedge is therefore. interchangeable with another wedge on the device according to the invention. A positioning wedge can also be adapted to several types of connections.
[0036] The positioning wedge 8 is truncated so as to leave the threads visible in an orientation corresponding to a measurement trajectory by dimensional sensors 3,4.
[0037] The positioning shim 8 allows the placement of the end of the threaded element 6, and of a calibration template 5, in a depth of field of the dimensional sensors such that the depth of field of the lasers of the dimensional sensors is constant, whatever the diameter of the threaded element. This depth of field can vary between 5 and 200 mm, but is preferably between 5 and 50 mm. This makes it possible to avoid changing the positioning of the dimensional sensors in the direction (z) perpendicular to the table.
[0038] The device of Figure 1 comprises two cylinders or sliding axes 12 connecting the positioning wedge 8 to the table 10.
[0039] When an operator positions the device according to the invention on one end of a threaded element 6, the positioning wedge 8 is brought around a thread of the threaded element 6, then the operator pushes the device towards the threaded element 6 using the handle 13, which facilitates gripping by the operator and the gestures of positioning and putting in place of the device. The positioning wedge 8 is pushed onto the thread, until the insertion surface 9, coming to bear on the thread crests of the thread of the threaded element 6, opposes any additional axial movement of the positioning wedge 8. The operator can continue to push the device towards the threaded element 6 and the sliding jacks or axes 12 so that the positioning cone is positioned on the perfect threads and until a bearing face 52 of the calibration template 5 contacts the end face of the threaded element 6.
[0040] More precisely, the contact between the end of the threaded element 6 and the end of the table 10 is established between the end of the threaded element 6 and a calibration template 5 mounted on the table 10. The calibration template 5 is visible in detail in Figure 3. The calibration template 5 is a part specifically machined with great precision, certain dimensions of which are perfectly known and entered in a memory of an electronics of the device 1. The calibration template 5 comprises a transverse portion 51 ensuring the positioning and fixing of the calibration template 5 on the table 10 of a part, and, on the other hand, of which a flat front surface or bearing face 52 is intended to come into contact with an end of threaded element 6. The calibration template 5 comprises a longitudinal portion 53 having reference lengths whose dimensions are perfectly known. The reference lengths are delimited by surfaces. These lengths are therefore predetermined and serve as references for the device, and are entered in a memory of processing electronics of the device. These reference surfaces are arranged to allow the device to correct the data recorded by the dimensional sensors 3, 4 which are dependent on the positions and orientations of said dimensional sensors 3, 4 relative to the threaded element 6 and to the calibration template 5.The corrections are determined from measurements made by the dimensional sensors 3, 4 on the calibration template 5 and the comparison of the measurements made with the values of the predetermined reference lengths. Correction factors can be calculated from this comparison. Thus, from first measurements made on the calibration template 5, the data acquisition is corrected for the measurements made on the thread of the threaded element 5 with the correction factors thus calculated.
[0041] The calibration template 5 is positioned on the measurement path of the dimensional sensors 3, 4 so as to allow calibration at each measurement operation on a threaded element 6.
[0042] The calibration template 5 comprises a bearing face 52 on its transverse portion 51 arranged to come into contact with an end face of the threaded element 6. The bearing face 52 is perpendicular to the axis of the frustoconical insertion surface 9 of the positioning wedge 8. In combination with the action of the positioning wedge 8 on the thread, the support of the bearing face 52 on the end face of the threaded element 6 makes it possible to lock the device on the threaded element 6 to carry out a measurement, and to define an orthogonal dimensional reference mark.
[0043] In particular, the calibration template 5 comprises an engagement flank reference surface 54, a load flank reference surface 55, an axial length reference surface 56, a radial length reference surface 57. Thus the engagement flank reference surface 54 has an orientation substantially identical to the orientation of a flank surface engagement of a thread of the threaded element 6 to be measured, in a similar manner, the bearing flank reference surface 55 has an orientation substantially identical to the orientation of a bearing flank surface of a thread of the threaded element 6. This makes it possible to improve the measurement accuracy on the thread flanks. The axial length reference surface 56 is delimited by two surfaces detaching from the axial length reference surface. The length of the axial length reference surface 56 corresponds to an axial reference distance, and makes it possible to improve the measurement accuracy of the thread crests and roots. The radial length reference surface is materialized by recesses perpendicular to the axial length reference surface 56.
[0044] The longitudinal portion 53 is located in the extension of the truncated portion of the positioning wedge 8. In other words, the longitudinal portion 53 is on the measurement path of the dimensional sensors 3, 4.
[0045] The device also comprises a longitudinal reference extension 11 on the calibration template 5. This longitudinal reference extension 11 is of known dimension, so as to define a reference distance Dr, delimited on the one hand by a surface of the longitudinal reference extension 11, for example the surface facing the transverse portion 51, and a surface of the transverse portion 51. This makes it possible to identify, through the measurements carried out, a deviation of the trajectory of the dimensional sensors 3, 4 relative to a theoretical trajectory parallel to the axis of the threaded element.
[0046] The positioning wedge 8 and the calibration template 5 make it possible to position the device on the threaded element 6 in a repeatable manner and also in such a way as to make the main axis of the threaded element 6 coincide as much as possible with a measuring axis of the device according to the invention, that is to say with a minimal deviation of the measuring axis relative to the main axis of the threaded element 6.
[0047] In the embodiment of Figure 1, the two dimensional sensors 3, 4 are identical and are line laser sensors or laser profiteers. A prototype was built using GOCATOR 2510 sensors from LMI Technologies. The two dimensional sensors 3, 4 are mounted on a support arranged to allow position and orientation adjustment on the three axes. Also, the dimensional sensors 3, 4 are mounted in translation so as to move in a direction substantially corresponding to the direction main axis or principal axis (x), so that the respective beams of the two laser profilers can cover all the areas of interest of the end of the threaded element, namely the thread or threads, any functional surfaces and other parts of the threaded end, or even the entire end of the threaded element. The displacement along the translation axis of the dimensional sensors 3, 4 is measured by a linear encoder.
[0048] Line laser sensors emit a laser beam centered on a line of sight, so that the projection of the laser beam forms a line on a surface to be measured. The laser measurement is synchronized with the measurement of an optical encoder determining a longitudinal position along the main axis (x). This makes it possible to reconstruct a complete profile from two partial profiles traced digitally by the line laser sensors. The distances of the points of the projected line are evaluated by an internal camera-type image capture device, the laser beam being emitted in a pulsed manner and the time of flight of the light rays being measured so as to determine a distance to the dimensional sensor. The line of sight is substantially perpendicular to the face of the laser emitter.
[0049] An orthogonal reference frame attached to the measuring device and called the measuring reference frame (O, x, y, z) is defined. The main axis (x) is substantially aligned with a main axis x' of the thread of the threaded element 6 to be measured. This alignment is physically obtained by placing the positioning shim 8 on the threaded element. The secondary axis (y) is in a plane parallel to an upper surface of the calibration template 5 and the tertiary axis (z) is perpendicular to an upper surface of the calibration template 5.
[0050] The respective viewing directions of each of the sensors or respective optical measurement directions form, in a plane containing the main axis and the tertiary axis (O, x, z), an angle A between the first viewing direction and the second viewing direction which is between 30° and 70°. Preferably, the angle A is between 40° and 60°. With such an angle between the two directions, it is possible to measure the geometric data of the thread flanks, whether these flanks have a negative angle or a positive angle. In particular, it is possible to carry out measurements on threads with a hook type profile or a dovetail type profile. It is also possible to carry out measurements on threads with variable pitch, which are also often associated with dovetail type profiles.
[0051] The respective viewing directions of each of the dimensional sensors are in opposition to each other, that is, the viewing direction of the first sensor is opposite to the viewing direction of the second sensor in projection onto the main axis (x).
[0052] The respective viewing directions can form a non-zero misalignment angle B in a plane containing the major axis (x) and the minor axis (y). This angle is as close to zero as possible, but it is naturally imperfect in reality. To improve measurement accuracy, this misalignment angle is compensated by a calibration step in the measurement process which involves performing a measurement step on the calibration template.
[0053] Furthermore, the displacement of the dimensional sensors 3, 4 is not strictly parallel to the main axis x' of the threaded element to be measured, but in a direction which may have a first deviation angle a relative to the first axis (x) in the plane (O, x, y), a second deviation angle P relative to the first axis (x) in the plane (O, x, z), and a third deviation angle y relative to the third axis (z) in the plane (O, y, z), the first measurement step on the calibration template 5 makes it possible to determine correction factors which are a function of the first deviation angle a, the second deviation angle P and the third deviation angle y.
[0054] The next step comprises the acquisition of a first set of measurements by the first dimensional sensor 4 and a second set of measurements by the second dimensional sensor 5. The measurement set concerns the thread of the threaded element, but may concern other functional surfaces of the threaded element, such as a stop surface, a sealing surface. These surfaces must in fact comply with very precise dimensional criteria because they have critical functionalities of ensuring an assembly torque and a seal against liquids and / or gases in cooperation with a corresponding surface of a corresponding threaded element.
[0055] When a measurement is carried out by the dimensional measuring device 1 on a threaded element, the electronics are arranged to receive the measurements from the first dimensional sensor 3 and from a linear encoder whose output is representative of the positioning of the first dimensional sensor 3, the electronics are arranged to reconstruct a first partial profile of the threaded element investigated. in a similar manner, the electronics are arranged to receiving the measurements from the second dimensional sensor 4 and from the linear encoder whose output is representative of the positioning of the second dimensional sensor 4, the electronics are arranged to reconstruct a second partial profile of the threaded element investigated.
[0056] When measuring on the threaded element, the first and second dimensional sensors 3, 4 carry out measurements on the threaded element and also on the calibration template 5. The electronics are arranged to record the measurements carried out on the calibration template 5 and to determine from the measurements carried out values measured on the surfaces delimiting the reference lengths, including the reference values engagement flank reference surface 54, a load flank reference surface 55, an axial length reference surface 56, a radial length reference surface 57, and to determine correction factors by comparison between the measurements carried out on these surfaces and the values of the actual lengths of the reference surfaces.
[0057] When measuring on the threaded element, the first and second dimensional sensors 3, 4 also carry out measurements on the longitudinal reference extension 11, and determine a measured reference length value Dr'. By comparing the measured reference length value Dr' with the reference length Dr, the electronics are arranged to determine a measurement path correction factor related to the path of the first and second dimensional sensors 3, 4. This factor makes it possible to compensate for a deviation between the main axis of the threaded element and the displacement axis of the dimensional sensors 3, 4.
[0058] The displacement of the dimensional sensors 3, 4 can be done at variable speed, for example at a first lower displacement speed to make a denser acquisition of measurement points, and at a second displacement speed greater than the first displacement speed where it is not necessary to have many measurement points of the surface. It is advantageous to have a slower speed and therefore more measurement points on functional surfaces such as abutment or sealing surfaces, or on surfaces which are very inclined relative to the main axis (x).
[0059] The electronics are arranged to construct a complete profile of the threaded element by joining the first partial profile and the second partial profile after processing the measured data taking into account the correction factors.
[0060] The electronics are arranged to overlay the full profile with a digitized profile comprising two profile plots, a maximum profile and a minimum profile delimiting a profile envelope. The electronics are arranged to display a conforming result to the user when the full profile is located entirely within the envelope, or to display a non-conforming result if the full profile is not entirely within the envelope.
[0061] The electronics are arranged to allow comparison of the complete profile with reference geometric shapes.
[0062] The first partial profile may include measurement points on the thread crests, thread root, and one of the flanks, for example the engagement flanks, due to the orientation of the first line laser sensor relative to the thread, while the second partial profile may include measurement points on the thread crests, thread root, and the other flank, and relative to the example given, load flanks. Thus, the first partial profile and the second partial profile may have measurement points on common parts of the measured surfaces, and measurement points on distinct parts of the measured surfaces, due to the distinct and opposite orientations of the two line laser sensors. The combination of the first partial profile and the second partial profile will therefore reveal complementary sets of points and sets of overlapping points.The complete profile as a union of the two partial profiles corrected after data processing includes measurement points on all investigated surfaces.
[0063] Thus, the device according to the invention makes it possible to implement a method of dimensional measurement of one end of a threaded element 1, which comprises the following successive steps.
[0064] In a first step, the device 1 is brought onto the threaded element 6 and mounted there, so that the positioning wedge 8 is placed on the thread, more precisely on the thread crests of the thread of the threaded element 6, and more precisely on perfect thread crests. This positioning is done by axially introducing the positioning wedge 8 around the end of the threaded element 6 and until the positioning wedge 8 opposes any further movement, then the chassis is pushed by an operator using the handle 13 towards the end of the threaded element, so that the jacks 12 compress and until the stop face 52 of the calibration template 5 contacts an end face of the threaded element 6. Thus the measuring device 1 is positioned so as to minimize offsets between the axis of the threaded element 6 and a main axis x of a reference mark attached to the measuring device.
[0065] In a second step, a data acquisition phase is launched, during which the dimensional sensors 3, 4 will travel a rectilinear path passing through the measuring template and the surfaces to be measured of the threaded element 6, comprising at least one thread, and optionally a stop surface, and optionally also a sealing surface.
[0066] A data acquisition step is carried out on the measuring template 5. Then, a step of determining corrective measurement factors is carried out by comparison between the predetermined values corresponding to the actual values of the dimensions of certain surfaces of the calibration template 5 with the values measured on said surfaces by the dimensional sensors 3, 4.
[0067] A data acquisition step is carried out on the surface(s) to be measured of the threaded element, comprising at least one thread, and optionally a stop surface, and optionally also a sealing surface, so as to obtain a first partial profile resulting from the measurements carried out by the first dimensional sensor 3 and the linear encoder and to obtain a second partial profile resulting from the measurements carried out by the second dimensional sensor 4.
[0068] The partial profiles are then combined, after corrections are applied with the measurement correction factors, into a complete profile or full profile.
[0069] The complete profile can then be subjected to a filtering or smoothing operation.
[0070] The complete profile obtained is then compared to a digital profile representing an envelope of minimum and maximum dimensions of the thread profile, and a thread conformity result is obtained, positive if the complete profile is entirely contained within the envelope defined by the digitalized profile, or negative otherwise.
[0071] Finally, dimensional measurements can be carried out on the complete profile, such as, but not limited to: determination of radii of curvature (by marking circles), direct linear measurement between points of the profile.
[0072] Figure 4 schematically illustrates an alternative embodiment of the device of Figure 1 in the context of a female-type threaded element, i.e. having a thread on an internal surface of the threaded element. In this Figure 4, the elements identical or fulfilling the same function as those described above with regard to Figures 1 to 3 bear the same reference.
[0073] In the context of a large female threaded element 6 (not shown), the measuring device 1 is similar to the measuring device 1 described above with an orientation of the dimensional sensors 3, 4 adapted to emit a laser beam in the direction of the thread of the threaded element 6, and optionally a stop surface, and optionally also a sealing surface. By large threaded element 6 is meant a threaded element allowing the insertion of the dimensional sensors 3, 4 into said threaded element 6 with a minimum distance between the dimensional sensors 3, 4 and the surface(s) to be inspected of the threaded element 6. Typically, the distance between the dimensional sensors 3, 4 and the surface(s) to be inspected must be greater than the start of the measuring range of said dimensional sensors 3, 4.
[0074] However, if the internal diameter of the threaded element 6 does not allow the insertion of the dimensional sensors 3, 4 with a distance between said dimensional sensors 3, 4 and the surface(s) to be inspected greater than the start distance of the measuring range of said dimensional sensors 3, 4, the measuring device 1 comprises mirrors 17 (see figure 4) to orient the laser beams emitted by the dimensional sensors 3, 4 in the direction of the surface(s) to be inspected on the threaded element 6. The dimensional sensors 3, 4 are then mounted on the frame 2 to emit their laser beam in the direction of the mirrors 17, said mirrors 17 being mounted movably and orientably on the measuring device 1 to redirect the laser beams.
[0075] The measuring device 1 comprises a means for moving and guiding the mirrors 17, in the embodiment illustrated in FIG. 4 a guide rail 18. This displacement and guidance means is inserted into the threaded element 6 when positioning the measuring device 1 on the threaded element 6, typically, and, in a manner analogous to the positioning of the measuring device described above with reference to figures 1 to 3, when the frustoconical insertion surface of the positioning wedge and the bearing face are in support respectively against the top of the perfect threads and the end face of the threaded element 6.
[0076] The mirrors 17 are mounted on the guide rail 18 so as to be able to move along said guide rail 18, for example by means of an ad hoc motor. The position of the mirrors 17 is further controlled in a manner analogous to the position control of the dimensional sensors 3, 4 of FIGS. 1 to 3, for example by means of a linear encoder. The dimensional sensors 3, 4 are oriented so as to emit a laser beam towards a respective mirror 17. This laser beam is then reflected by said mirror 17 to impact the surface(s) to be inspected, for example the template, the thread of the threaded element 6, a stop surface and / or a sealing surface.
[0077] Advantageously, the mirrors 17 further have a configurable orientation, for example by means of an orientable mirror support or a pivot connection between the mirror 17 and the guide rail 18. Thus, the mirrors 17 are able to move and change orientation along the guide rail 18. This change of orientation could also be obtained by replacing the mirror 17 on the guide rail 18 with a mirror having the desired orientation.
[0078] The orientation of the mirrors 17 makes it possible to direct the laser beams emitted by the dimensional sensors according to the desired orientation. In other words, the adjustment of the orientation of the dimensional sensors 3, 4 in the embodiment illustrated in FIG. 1 is here replaced by the adjustment of the orientation of the mirrors 17, this orientation of the mirrors 17 defining the optical measurement directions of the dimensional sensors. It is thus possible, thanks to the respective orientation of the mirrors 17 and the dimensional sensors 3, 4, to define optical measurement directions forming an angle between the first viewing direction and the second viewing direction, for example an angle of between 30° and 70°, and preferably between 40° and 60°.
[0079] In another embodiment, the orientation of mirrors 17 is fixed, for example at 45° relative to the longitudinal axis of the threaded element 6, but the orientation of the dimensional sensors 3, 4 can be modified to impact the mirrors 17 with different angles, thus making it possible to orient the corresponding viewing directions. Furthermore, the mirrors 17 can take different shapes, for example flat, multi-sided, curved mirrors 17 or other to allow different orientations of the viewing directions. For example, it is possible to have two mirrors 17, one for each 3, 4 dimensional sensor, or on the contrary a single mirror 17 with a particular shape allowing the viewing direction to be oriented according to the orientation of the 3 or 4 dimensional sensor.
[0080] In a manner similar to the embodiment illustrated in FIG. 1, the calibration template 5 is positioned on the measurement trajectory of the dimensional sensors 3, 4 defined by the mirrors 17 so as to allow calibration at each measurement operation on a threaded element 6.
Claims
Claims
1. A device for measuring the dimensions of a threaded element 1 comprising a frame 2, the frame 2 comprising a first line laser sensor 3 having a first optical measurement direction and a second line laser sensor 4 having a second optical measurement direction, said second optical measurement direction forming a non-zero angle A with the first optical measurement direction in a plane containing the first optical measurement direction, the first line laser sensor 3 and the second line laser sensor 4 being movably mounted on the chassis 2 and having at least one measurement trajectory making it possible to carry out geometric data acquisitions of the threaded element 1 passing through a calibration template 5 and being able to pass through a portion of the threaded element 1,the device comprising an encoder arranged to determine a position of the first line laser sensor 3 and a position of the second line laser sensor 4 along a main axis (x) and electronics arranged to construct a first partial profile from the first line laser sensor 3 and a second partial profile from the second line laser sensor 4, the electronics being arranged to construct a complete profile from the first partial profile and the second partial profile as a function of the respective positions of the first line laser sensor 3 and the second line laser sensor, 4 and depending on at least one measurement carried out on the calibration template 5.
2. Measuring device according to claim 1, characterized in that said angle A is between 30° and 70°, preferably between 40° and 60°.
3. Measuring device according to one of claims 1 to 2, characterized in that the first line laser sensor 3 and the line laser sensor 4 are mounted in translation on the chassis 2.
4. Measuring device according to one of claims 1 to 3 in which the calibration template 5 comprises surfaces delimiting predetermined reference lengths.
5. Measuring device according to one of claims 1 to 4, in which the calibration template 5 comprises a bearing face 52 arranged to contact an end face of the threaded element 6 to be measured.
6. Measuring device according to one of claims 1 to 5 comprising a positioning wedge 8 arranged to be able to bear on the tops of threads of the threaded element 6.
7. Measuring device according to the preceding claim in which the positioning wedge 8 comprises a frustoconical insertion surface 9 having a frustoconical insertion surface axis and being capable of being in contact with the thread crests of the threaded element 6.
8. Measuring device according to claim 5 taken in combination with claim 6 or 7 in which said bearing face is perpendicular to the axis of the frustoconical insertion surface 9 of the positioning wedge 8.
9. Measuring device according to one of the preceding claims in which the calibration template 5 comprises an engagement flank reference surface 54, a load flank reference surface 55, an axial length reference surface 56, a radial length reference surface 57.
10. Measuring device according to one of the preceding claims in which the calibration template 5 comprises a longitudinal reference extension 11 defining a reference length Dr and the electronics are arranged to determine a measurement trajectory correction factor linked to the trajectory of the first and second line laser sensors 3, 4.
11. Measuring device according to one of the preceding claims in which the electronics are arranged to compare a digital thread profile comprising minimum and maximum dimensions with the complete profile and the electronics are configured to generate a thread conformity result.
12. Measuring device according to one of the preceding claims in which the electronics are arranged to carry out dimensional measurements of surfaces of the end of the threaded element 1.
13. A method of dimensional measurement of one end of a threaded member 1 comprising the steps of: - mounting on the threaded element 1 the measuring device according to one of the preceding claims - perform data acquisition with the first line 3 laser sensor and the second laser sensor line 4 on measuring template 5 - determine measurement correction factors and store them in an electronic memory - perform a second data acquisition on the end of the element fdeté 1 with the first laser sensor line 3 and the second laser sensor line 4 - generate a first partial profile from a first data set from the second data acquisition by the first line laser sensor 3 - generate a second partial profile from a second data set from the second data acquisition by the second line laser sensor 4 - generate a complete profile from the first partial profile, the second partial profile and the measurement correction factors.