Measuring tool

Abstract

A measuring tool (1) is configured to measure relative positioning defects between a first flange (7) of a first pipe (3) and a second flange (9) of a second pipe (5). The first flange (7) extending r

Description

TITLE: MEASURING TOOL TECHNICAL FIELD The present application relates to a tool for measuring relative positioning defects between two pipes, more specifically a tool for measuring relative positioning defects between a first flange of a first pipe and a second flange of a second pipe distant from the first flange, as well as a method for measuring relative positioning defects between a first flange of a first pipe and a second flange of a second pipe distant from the first flange, using such a measuring tool. The invention in particular applies to the positioning defects configured to be adjusted by a compensator sleeve, preferably made of elastomer. STATE OF THE ART During the operation of a nuclear unit, the maintenance of the hydraulic circuits important for safety forms part of the activities with high safety issues for which compliance with the timing is essential. On these systems, the elastomer compensator sleeves (ECS) play an important role in ensuring the sealing of the junctions between two pipes. These devices ensure the recovery of dynamic and static stresses. The excessive stresses contribute to their fatigue as well as to their wear and can lead to their rupture. On a nuclear site, the vibrations as well as the thermomechanical loads due to the passage of fluid at different temperatures are at the origin of these dynamic stresses. The main functions of an ECS are: - to protect the hydraulic circuit, by limiting the mechanical forces in the pipes, related to the dimensional variations in operation (thermal expansion, pressure / background effect, earthquake), - to absorb the vibrations, and to a lesser extent to reduce noise, and - to attenuate the effect of water hammer. The loads are absorbed by a specific bellows part made of flexible elastomer. The ECS manufacturers define maximum limitations for the defects recovered by an ECS. These defects are clearly identified by the manufacturers and the compliance with the tolerances is imperative in nuclear regulations. These defects are mainly: axial spacing also called extension / compression, parallelism also called angular displacement, lateral displacement also called concentricity defect. For example, the measurement values taken into consideration are the maximum or most penalizing measured values , and are therefore increased with regard to the reality of the stresses undergone by the ECS. Indeed, the maximum axial spacing value is in reality not necessarily located at the same point as the maximum lateral displacement value. The conformity of a mounting requires the compliance with the aforementioned tolerances. However, there is no device for measuring such defects in a reliable and simple manner. DISCLOSURE OF THE INVENTION One aim of the present application is to overcome the aforementioned drawbacks, by proposing a measuring tool for measuring the relative positioning defects between a first flange of a first pipe and a second flange of a second pipe distant from the first flange, at the installation point of an ECS, and this in a simple, accurate and quick manner. To this end, the invention proposes, according to a first aspect, a measuring tool configured to measure relative positioning defects between a first flange of a first pipe and a second flange of a second pipe distant from the first flange, the first flange extending radially about a reference axis X, the measuring tool comprising: - a body comprising a measuring support, an axial reference stop configured to be in axial abutment against the first flange, and a radial reference stop configured to be in radial abutment against the first flange, - a first strip slidably mounted radially on the body so that a first slide connection configured to be orthogonal to the reference axis X connects the body and the first strip, - a second strip slidably mounted axially on the first strip so that a second slide connection configured to be parallel to the reference axis X connects the first strip and the second strip, the second strip including a targeting element and a radial measuring stop configured to be in radial abutment against the second flange, the targeting element being configured to allow a user to mark a measuring point on the measuring support. Thus, thanks to such a measuring tool, it is easy to measure the relative positioning defects between the first flange and the second flange. The axial spacing defect along the reference axis X, the lateral displacement defect along an axis Y orthogonal to the reference axis X and the parallelism defect can be determined by marking measuring points on the measuring support. A measuring tool is therefore provided for measuring the relative positioning defects between a first flange of a first pipe and a second flange of a second pipe distant from the first flange in a simple, accurate and quick manner. Such a tool also saves time when taking the measurements, does not require any special skills, is particularly accurate, allows reporting the actual and not the maximum defects, allows determining three relative positioning defects from the measuring points taken, allows repeatability of the measurements with different users, and standardizes the way in which the measurements are taken. Another advantage is also not to scrap a compliant compensation sleeve because of a measurement method that does not take into account the actual relative positioning defects. According to a second aspect, the invention proposes a method for measuring relative positioning defects between a first flange of a first pipe and a second flange of a second pipe distant from the first flange, the method comprising the following successive steps: - mounting the measuring tool in accordance with the first aspect on the first flange so that the axial reference stop is in axial abutment against the first flange and the radial reference stop is in radial abutment against the first flange, - sliding the first strip relative to the body and the second strip relative to the first strip until the radial measuring stop is in contact with the second flange, then holding in position the second strip, - marking a measuring point by means of a measuring marker, the measuring point representing a relative positioning defect between the first flange and the second flange, - moving the measuring tool angularly about the reference axis X by a predetermined angle, - repeating the previous steps at least two preferably at least three times, until the measuring tool has covered an angular range of at least 90°, preferably at least 180°. Thus, thanks to such a measuring method, it is simple to measure the relative positioning defects between the first flange and the second flange. The axial spacing defect along the reference axis X, the lateral displacement defect along an axis Y orthogonal to the reference axis X and the parallelism defect can be determined by marking measuring points on the measuring support. A measuring method is therefore provided for measuring the relative positioning defects between a first flange of a first pipe and a second flange of a second pipe distant from the first flange in a simple and quick manner. The invention is advantageously and optionally supplemented by the following characteristics, taken alone or in any one of their technically possible combinations: - The axial reference stop is configured to be in axial abutment against the first flange along the reference axis X. - The radial reference stop is configured to be in radial abutment against the first flange along a radial axis Y orthogonal to the reference axis X. - The second flange of the second pipe is distant from the first flange in order to connect the first pipe to the second pipe by a compensation sleeve fixed on the first flange and on the second flange. - In the absence of a relative positioning defect between the first flange and the second flange, a compensation sleeve can be mounted between the first flange and the second flange and can be fixed on the first flange and on the second flange. - The body comprises a first radial guide rail and the first strip comprises a first slider, the first slider being slidably mounted on the first radial guide rail to form the first slide connection. Thus, the first slide connection is made in a simple and accurate manner. - The first slider comprises a first T-shaped groove axially sliding on the first radial guide rail. Thus, the first slide connection is made in a simple and accurate manner. - The first radial guide rail extends longitudinally parallel to a radial axis Y orthogonal to the reference axis X. - The first slider carries a guide gib. Thus, the accuracy of the first slide connection is improved. - The first strip comprises a second axial guide rail and the second strip comprises a second slider, the second slider being slidably mounted on the second axial guide rail to form the second slide connection. Thus, the second slide connection is made in a simple and accurate manner. - The second axial guide rail extends longitudinally parallel to the reference axis X. - The second slider comprises a second T-shaped groove axially sliding on the second axial guide rail. Thus, the second slide connection is made in a simple and accurate manner. - The second strip comprises a finger whose first finger part extends axially from the second slider and whose second finger part extends radially from the end of the first finger part distant from the second slider, the end of the second finger part distant from the first finger part forming the radial measuring stop. - The first finger part carries the targeting element. - The measuring tool further comprises a clamping jaw, configured to clamp the body on the first flange together with the axial reference stop. Thus, the mounting of the measuring tool on the first flange is facilitated. - The body comprises a third axial guide rail, the clamping jaw being slidably mounted axially on the third axial guide rail so that a third slide connection configured to be parallel to the reference axis X connects the clamping jaw and the body. Thus, the positioning and the mounting of the measuring tool on the first flange is carried out in a simple and accurate manner. - The clamping jaw comprises a third T-shaped groove axially sliding on the third guide rail. Thus, the third slide connection is made in a simple and accurate manner. - The clamping jaw is configured to axially bear on the first flange, on the face opposite to the face configured to be in contact with the axial reference stop. - The clamping jaw is configured to bear on a sleeve flange of a compensation sleeve, the sleeve flange being fixed and bearing on the first flange. - The measuring tool further comprises an adjustment screw, the adjustment screw being configured to adjust and maintain the axial position of the clamping jaw relative to the body. Thus, the adjustment of the positioning of the measuring tool relative to the first flange is made in a simple manner. - The adjustment screw passes axially through a hole in the body and is engaged in a tapped hole in the clamping jaw. -The radial reference stop comprises two planar surfaces inclined relative to each other to form an inverted V, the two planar surfaces extending along two axially intersecting planes, preferably along an axis configured to be parallel to the reference axis X. Thus, the radial reference stop is made in a simple manner while being adapted to first flanges of different diameters. - The measuring support is formed by a plate carrying a measurement sheet. Thus, the measuring support is made in a simple manner. - The plate extends parallel to the first slide connection and to the second slide connection. - The plate extends axially parallel to the reference axis X and radially orthogonal to the reference axis X. - The plate includes two axial rims each delimiting an axial slot for holding the measurement sheet. Thus, the holding of the measurement sheet is made in a simple and accurate manner. - Each axial rim is orthogonal to the first radial guide rail. - The targeting element includes a tangential targeting hole opening out onto the measuring support, which is configured to allow a user to mark a measuring point on the measurement sheet by means of a measurement marker. Thus, the marking of measuring points is simple and accurate. - The measuring tool includes a first position-holding element configured to hold in position the first strip on the body. Thus, the measurement via the measuring tool is simpler to take because the first strip is held in position on the body. - The first position-holding element is a screw axially engaged in a tapped hole of the first strip and configured to rest on the guide gib. Thus, the first position-holding element is particularly simple to handle. - The measuring tool includes a second position-holding element configured to hold in position the second strip on the first strip. Thus, the measurement via the measuring tool is easier to take because the second strip is held in position on the first strip. - The second position-holding element is a screw tangentially engaged in a tapped hole of the second strip and configured to bear on the second axial guide rail, via a second guide gib. Thus, the second position-holding element is particularly simple to handle. - The predetermined angle is comprised between 30° and 60°, preferably equal to 30°, 45° or 60°. - The angular range is equal to 90° or 180°. - The measuring method is such that it further comprises the following successive steps, carried out previously and only once: - marking an axis X' on the measuring support, preferably on the measurement sheet, at the distance corresponding to the radial distance between the first flange in contact with the radial reference stop and the center of the targeting element, - measuring an axial spacing Dmes along the reference axis X between the first flange and the second flange at an angular position about the axis X, - determining an axial offset Da such that Da = Dref - Dmes, Dref being a predetermined reference distance, and Dmes being the axial spacing, - mounting the measuring tool on the first flange so that the axial reference stop is in axial abutment against the first flange and the radial reference stop is in radial abutment against the first flange, - sliding the first strip relative to the body and the second strip relative to the first strip until the radial measuring stop is in contact with the second flange, then holding in position the second strip, - marking a preliminary measuring point by means of a measuring marker, the preliminary measuring point representing a relative positioning defect between the first flange and the second flange, - dismounting the measuring tool from the first flange, and preferably removing the measurement sheet from the measuring tool, - marking an axis Y' on the measurement sheet, the axis Y' being orthogonal to the axis X' and passing at a minimum distance from the preliminary measuring point equal to the value of the axial offset Da, and preferably replacing the measurement sheet in the measuring tool. Thus, the measuring points are visually identified relative to the axis X' representing the axial spacing, the axis Y' representing the lateral displacement, the origin resulting from the intersection of the axis X' and the axis Y' and representing an absence of relative positioning defect between the first flange and the second flange. - The measuring method is such that it further comprises the following steps: - marking two axial spacing tolerance limit points on the axis X', from values derived from a tolerance table of a compensation sleeve configured to be mounted between the first flange and the second flange in the absence of a relative positioning defect between the first flange and the second flange, - marking two lateral displacement tolerance limit points on the axis Y', from values derived from a tolerance table of a compensation sleeve configured to be mounted between the first flange and the second flange in the absence of a relative positioning defect between the first flange and the second flange, - drawing a non-intersecting quadrilateral whose vertices are the two axial spacing tolerance limit points and the two lateral displacement tolerance limit points, the non-intersecting quadrilateral internally delimiting a tolerance area. Thus, whether the measuring points are located in the tolerance area or outside the tolerance area is visually and directly determined. If at least one measuring point is located outside the tolerance area, the relative positioning defects between the first flange and the second flange are such that a compensation sleeve cannot be mounted without undergoing degradation. It is therefore necessary to correct the relative positioning of the first flange and of the second flange, for example by lengthening or shortening the first pipe and / or the second pipe to correct an axial spacing defect, and / or by realigning the first flange and the second flange to correct a lateral displacement defect, and / or by diagonally cutting a portion of the first pipe and / or of the second pipe to correct a parallelism defect. In this regard, it is particularly simple to measure a parallelism defect a between the first flange and the second flange. For example, it is possible to make two measuring points at opposite angular positions of the measuring tool about the reference axis X, in other words at 180° from each other, and then apply the formula: a = sin-1(d / Dext), where a is the parallelism defect, d is the maximum distance along the axis X' between two measuring points, and Dext is the outside diameter of the second flange. Thus, the measurement of the parallelism defect can be read on the survey sheet: simply measure the distance between the rightmost point of the survey (maximum extension) and the leftmost point of the survey (maximum compression). This distance represents the angular defect in millimeters. DESCRIPTION OF THE FIGURES Other characteristics, aims and advantages of the invention will emerge from the detailed description below, which is purely illustrative and non-limiting, and which should be read in relation to the appended drawings, given as non-limiting examples and in which: [Fig. 1] represents a perspective view of a measuring tool in accordance with one embodiment, mounted on a first flange of a first pipe and in radial abutment against a second flange of a second pipe distant from the first flange, a compensation sleeve being mounted between the first flange and the second flange; [Fig. 2] represents a perspective view of a body of the measuring tool represented in Figure 1; [Fig. 3] represents a perspective view (Figure 3a) and a top view (Figure 3b) of a first strip of the measuring tool represented in Figure 1; [Fig. 4] represents a front view of a second strip of the measuring tool represented in Figure 1; [Fig. 5] represents a perspective view (Figure 5a) and a bottom view (Figure 5b) of the second strip of the measuring tool represented in Figure 1; [Fig. 6] represents a perspective view of a clamping jaw of the measuring tool represented in Figure 1; [Fig. 7] represents a perspective view of one variant of the clamping jaw of the measuring tool; [Fig. 8] is a diagram of a measuring method in accordance with one embodiment; [Fig. 9] represents a measurement sheet of the measuring tool represented in Figure 1. In all the figures, similar elements bear identical references. DETAILED DESCRIPTION Figure 1 represents a measuring tool 1 in accordance with one embodiment, disposed between a first pipe 3 and a second pipe 5. More specifically, the measuring tool 1 is disposed between a first flange 7 of the first pipe 3 and a second flange 9 of the second pipe 5 distant from the first flange 7. The first flange 7 extends radially about a reference axis X. The second flange 9 is distant from the first flange 7 in order to connect the first pipe 3 to the second pipe 5 by a compensation sleeve 11 fixed on the first flange 7 and on the second flange 9. In this example, the diameter of the first flange 7 is equal to the diameter of the second flange 9. The measuring tool 1 is configured to measure relative positioning defects between the first flange 7 and the second flange 9. In the absence of a relative positioning defect between the first flange 7 and the second flange 9, the compensation sleeve 11 can be mounted between the first flange 7 and the second flange 9 and can be fixed on the first flange 7 and on the second flange 9, and this, without undergoing degradation. Advantageously, the nominal diameter DN of the first pipe and of the second pipe is standardized, and the diameter Dext of the first flange 7 and of the second flange 9 is also standardized and is thus set as a function of the nominal diameter DN. For example, when DN = 100 mm, then Dext = 220 mm. The table below presents one example of tolerances permissible by the compensation sleeve 11, as a function of the nominal diameter DN and of a nominal axial spacing value between the first flange 7 and the second flange 9. [Table 1] Dimensional characteristics Maximum permissible displacement Nominal diameter (DN) in mm Nominal length (LN) in mm axial in compression (LN-LC) in mm axial in extension (LE - LN) in mm lateral (R) in mm angular (a) in degrees 32 130 25 10 15 20 40 130 25 10 15 20 50 130 25 10 15 20 65 130 25 10 15 20 80 130 25 10 15 17 100 130 25 10 15 14 125 130 25 15 15 14 150 130 20 15 15 10 200 130 20 20 15 10 250 130 15 25 15 8 300 130 15 30 15 7 Thus, for example, when DN = 100 mm, the nominal axial spacing (LN) between the first flange 7 and the second flange 9 is equal to 130 mm, the maximum permissible axial compression is equal to 25 mm, the maximum permissible axial extension is equal to 10 mm, 5 the maximum permissible lateral displacement defect (denoted R in Table 1) is equal to 15 mm, and the maximum permissible parallelism defect a is equal to 14°. The measuring tool 1 comprises a body 13, also represented in Figure 2, a first strip 15, also represented in Figure 3 (Figures 3a and 3b), and a second strip 17, also represented in 10 Figure 4 and in Figure 5 (Figures 5a and 5b). As represented in Figure 1, the first strip 15 is slidably mounted radially on the body 13. Thus, a first slide connection connects the body 13 and the first strip 15. Advantageously, the first slide connection is orthogonal to the reference axis X. The second strip 17 is slidably mounted axially on the first strip 15. Thus, a second slide 15 connection connects the first strip 15 and the second strip 17. Advantageously, the second strip is parallel to the reference axis X. The body 13 comprises a measuring support 19, an axial reference stop 21 and a radial reference stop 23. Preferably, the measuring support 19 is formed by a plate 25 carrying a measurement sheet 27, the latter also being called a survey sheet. Advantageously, the plate 25 extends axially parallel to the reference axis X and radially orthogonal to the reference axis X. In other words, the plate 25 extends parallel to the first slide connection and to the second slide connection. Preferably, the plate 25 includes two axial rims 29, 31 each delimiting an axial slot 33, 35 for holding the measurement sheet 27. Advantageously, the axial reference stop 21 is in axial abutment against the first flange 7 along the reference axis X, and the radial reference stop 23 is in radial abutment against the first flange 7 along a radial axis Y orthogonal to the reference axis X. Advantageously, the radial reference stop 23 comprises two planar surfaces S1, S2 inclined relative to each other to form an inverted V. Thus, the two planar surfaces S1, S2 extend along two axially intersecting planes, preferably along an axis parallel to the reference axis X. Advantageously, the body 13 also includes a first radial guide rail 37. The first radial guide rail 37 extends longitudinally parallel to the radial axis Y. Preferably, each axial rim 29, 31 is orthogonal to the first radial guide rail 37. Advantageously, the first strip 15 comprises a first slider 39 and a second axial guide rail 41. The first slider 39 is slidably mounted on the first radial guide rail 37 to form the first slide connection. Preferably, the first slider 39 comprises a first T-shaped groove 43, in particular visible in Figure 3 (Figure 3b), sliding axially on the first radial guide rail 37. Advantageously, the first slider 39 carries a guide gib 45, which is preferably housed in a lateral part 46 of the first groove 43. The second axial guide rail 41 extends longitudinally parallel to the reference axis X. Advantageously, the second strip 17 includes a targeting element 47 and a radial measuring stop 48 configured to be in radial abutment against the second flange 9. The targeting element 47 allows a user to mark a measuring point on the measuring support 19. Preferably, the radial measuring stop 48 has an axial thickness equal to that of the second flange 9. Advantageously, the radial measuring stop 48 is aligned with the second flange 9 when the radial measuring stop 48 is in radial abutment against the second flange 9. Advantageously, the second strip 17 comprises a second slider 49 and a finger 51. The second slider 49 is slidably mounted on the second axial guide rail 41 to form the second slide connection. Preferably, the second slider 49 comprises a T-shaped guide hole 53 configured to axially slide on the second axial guide rail 41 of the first strip 15. The finger 51 is such that a first finger part 55 extends axially from the second slider 49 and a second finger part 57 extends radially from the end of the first finger part 55 distant from the second slider 49, preferably parallel to the axis Y and in the direction of the reference axis X. Preferably, the first finger part 55 carries the targeting element 47. Advantageously, the end of the second finger part 57 distant from the first finger part forms the radial measuring stop 48. Preferably, the targeting element 47 extends from the first finger part 55 toward the measuring support 19. Advantageously, the targeting element 47 is located in an outgrowth protruding from the first finger part 55. Preferably, the targeting element 47 is in contact with the measurement sheet 27. Advantageously, the targeting element 47 includes a tangential targeting hole 59 opening out onto the measuring support 19. The tangential targeting hole 59 allows a user to mark a measuring point on the measurement sheet 27 by means of a measurement marker, such as a pencil or pen. Preferably, the tangential targeting hole 59 is orthogonal to the reference axis X and to the radial axis Y. Preferably, the measuring tool 1 includes a first position-holding element 61 configured to hold in position the first strip 15 on the body 13. Advantageously, the first position-holding element 61 is a screw axially engaged in a tapped hole in the first strip 15 and configured to bear on the guide gib 45. Advantageously, the measuring tool 1 includes a second position-holding element 61' configured to hold in position the second strip 15 on the first strip 17. Advantageously, the second position-holding element 61' is identical to the first position-holding element 61. Preferably, the second position-holding element 61' is a screw tangentially engaged in a tapped hole 63 of the second strip 35 and configured to bear on the second axial guide rail 41, via a second guide gib. This second guide gib is held by the screw tangentially engaged in the tapped hole 63. Advantageously, the second guide gib is housed in a lateral part 64 of the T-shaped guide hole 53. Preferably, the second guide gib is introduced on the side of the targeting element 47. Advantageously, the second guide gib is identical to the guide gib 45. Advantageously, the measuring tool 1 further comprises a clamping jaw 67, which is also represented in Figure 6. The clamping jaw 67 clamps the body 13 on the first flange 7 together with the axial reference stop 21. As represented in Figure 1, the clamping jaw 67 bears on a sleeve flange 71 of the compensation sleeve 11. The sleeve flange 71 is fixed and bearing on the first flange 7. Preferably, the body 13 comprises a third axial guide rail 69, the clamping jaw 67 being slidably mounted axially on the third axial guide rail 69 so that a third slide connection parallel to the reference axis X connects the clamping jaw 67 and the body 13. Advantageously, the clamping jaw 67 comprises a third T-shaped groove 73 sliding axially on the third guide rail 69. Preferably, the measuring tool 1 further comprises an adjustment screw 75. The adjustment screw 75 is configured to adjust and maintain the axial position of the clamping jaw 67 relative to the body 13. Advantageously, the adjustment screw 75 axially passes through a hole 76 in the body 13 and is engaged in a tapped hole 77 in the clamping jaw 67. According to one variant of the clamping jaw 67 represented in Figure 7, the clamping jaw 67 is dimensioned such that the axial dimension of the clamping jaw 67 is shorter according to this variant. Advantageously, according to this variant, the clamping jaw 67 is configured to axially bear on the first flange 7, on the face opposite to the face configured to be in contact with the axial reference stop 21. Figure 8 represents the main steps of a method for measuring relative positioning defects between a first flange 7 of a first pipe 3 and a second flange 9 of a second pipe 5 distant from the first flange 7. Thus, the measuring tool 1 previously described is configured to implement the measuring method described below. Such a measuring method includes the following successive steps: - P100 mounting the previously described measuring tool 1 on the first flange 7 so that the axial reference stop 21 is in axial abutment against the first flange 7 and the radial reference stop 23 is in radial abutment against the first flange 7, preferably adjusting the clamping jaw 67 using the adjustment screw 75 to clamp the body 13 on the first flange 7 together with the axial reference stop 21, - P110 sliding the first strip 15 relative to the body 13 and the second strip 17 relative to the first strip 15 until the radial measuring stop 48 is in contact with the second flange 9, then holding in position the second strip 17, - P120 marking a measuring point by means of a measuring marker, the measuring point representing a relative positioning defect between the first flange 7 and the second flange 9, - P130 moving the measuring tool 1 angularly about the reference axis X with a predetermined angle, - P140 repeating the previous steps at least two preferably at least three times, until the measuring tool 1 has covered an angular range of at least 90°, preferably at least 180°. Advantageously, the predetermined angle is comprised between 30° and 60°. Preferably, the predetermined angle is equal to 30°, 45° or 60°. Advantageously, the angular range is equal to 90° or 180°. Advantageously, the measuring method further includes the following successive steps, carried out prior to the steps described above and only once: - P10 marking an axis X' on the measuring support 19, preferably on the measurement sheet 27 as represented in Figure 9, at the distance corresponding to the radial distance between the first flange 7 in contact with the radial reference stop 23 and the center of the targeting element 47, - P20 measuring an axial spacing Dmes along the reference axis X between the first flange and the second flange at an angular position about the axis X, - P30 determining an axial offset Da such that Da = Dref - Dmes, Dref being a predetermined reference distance, and Dmes being the axial spacing, - P40 mounting the measuring tool 1 on the first flange 7 so that the axial reference stop 21 is in axial abutment against the first flange 7 and the radial reference stop 23 is in radial abutment against the first flange 7, preferably adjusting the clamping jaw 67 using the adjusting screw 75 to clamp the body 13 on the first flange 7 together with the axial reference stop 21, - P50 sliding the first strip 15 relative to the body 13 and the second strip 17 relative to the first strip 15 until the radial measuring stop 48 is in contact with the second flange 9, then holding in position the second strip 17, preferably holding in position the first strip 15 by the first position-holding element 61, - P60 marking a preliminary measuring point by means of a measurement marker, the preliminary measuring point representing a relative positioning defect between the first flange 7 and the second flange 9, - P70 dismounting the measuring tool 1 from the first flange 7, and preferably removing the measurement sheet 27 from the measuring tool 1, - P80 marking an axis Y' on the measurement sheet 27, the axis Y' being orthogonal to the axis X' and passing at a minimum distance from the prior measuring point equal to the value of the axial offset Da, and preferably replacing the measurement sheet 27 in the measuring tool 1. Advantageously, the radial distance is measured along the radial axis Y. Optionally, step P50 is such that the radial measuring stop 48 is aligned with the second flange 9, preferably such that a lateral edge of the radial measuring stop 48 is aligned with the face of the second flange 9 oriented towards the compensation sleeve 11, so that the lateral edge of the radial measuring stop 48 and the face of the second flange 9 are at the same axial position along the reference axis X. Advantageously, the measuring method is such that it further comprises the following steps: - P85 marking two axial spacing tolerance limit points E, F on the axis X', from values derived from a tolerance table of the compensation sleeve 11 configured to be mounted between the first flange 7 and the second flange 9 in the absence of a relative positioning defect between the first flange 7 and the second flange 9, - P90 marking two lateral displacement tolerance limit points G, G' on the axis Y', from values derived from a tolerance table of the compensation sleeve 11 configured to be mounted between the first flange 7 and the second flange 9 in the absence of a relative positioning defect between the first flange 7 and the second flange 9, - P95 drawing a non-intersecting quadrilateral L1, L2, L3, L4 whose vertices are the two axial spacing tolerance limit points E, F and the two lateral displacement tolerance limit points G, G', the non-intersecting quadrilateral L1, L2, L3, L4 internally delimiting a tolerance area. Thus, whether the measuring points are located in the tolerance area or outside the tolerance area is determined visually and directly. If at least one measuring point is located outside the tolerance area, the relative positioning defects between the first flange 7 and the second flange 9 are such that a compensation sleeve 11 cannot be mounted without undergoing degradation. It is therefore necessary to correct the relative positioning of the first flange 7 and of the second flange 9, for example by lengthening or shortening the first pipe 3 and / or the second pipe 5 to correct an axial spacing defect, and / or by realigning the first flange 7 and the second flange 9 to correct a lateral displacement defect, and / or by diagonally cutting a portion of the first pipe 3 and / or of the second pipe 5 to correct a parallelism defect. In this regard, it is particularly simple to measure a parallelism defect a between the first flange 7 and the second flange 9. For example, it is possible to make two measuring points at opposite angular positions of the measuring tool 1 about the reference axis X, in other words at 180° from each other, then to carry out a step of calculating the parallelism defect a by applying the formula: ames = sin-1(d I Dext), where ames is the parallelism defect, d is the maximum distance along the axis X' between two measuring points, and Dext is the external diameter of the second flange 9. Alternatively, the value of d is compared to a value dmax, with dmax=Dext . sina, where dmax is the maximum permissible distance along the axis X' between two measuring points, a is the maximum permissible parallelism defect, and Dext is the outside diameter of the second flange 9. This allows measuring the defect directly on the measurement sheet 27 by simply measuring the distance d between the rightmost point and the leftmost point and by comparing it to this value dmax. As a result, the three defects appear on the measurement sheet 27. For example, when DN = 100 mm, the nominal axial distance between the first flange 7 and the second flange 9 is equal to 130 mm, the maximum permissible axial compression is equal to 25 mm, the maximum permissible axial extension is equal to 10 mm, the maximum permissible lateral displacement (noted R in Table 1) is equal to 15 mm, and the maximum permissible parallelism defect a is equal to 14°. Point E is then placed at -25 mm on the axis X', point F is placed at +10 mm on the axis X', and points G and G' are placed at 15 mm on the axis Y', on either side of the axis X'. The empty measurement sheet 27 can be used for all the compensator sleeves of this manufacturer, of this type, of this reference and of this size. It will not need to be redone during a future inspection. This measurement sheet is valid if the ECS is in place (operational inspection). Otherwise (inspection of the position of the flanges, with the ECS dismounted during maintenance), the tooling is used with the second jaw shorter. In other words, the variant of the clamping jaw 67 represented in Figure 7 is used in this case. If all the measuring points are within the tolerance area, or on the lines L1, L2, L3 or L4, the compensation sleeve 11 is not deformed beyond the permissible tolerances and the mounting of the compensation sleeve 11 between the first flange 7 and the second flange 9 is then determined to be acceptable. If a single measuring point is outside the tolerance area, it is necessary to correct the relative positioning of the first flange 7 and of the second flange 9, as described above, in order to allow the mounting of a compensation sleeve 11 without it being degraded. If a compensation sleeve 11 is already mounted, the compensation sleeve 11 5 undergoes an out-of-tolerance deformation and it must be scrapped and replaced.

Claims

1. A measuring tool (1) configured to measure relative positioning defects between a first flange (7) of a first pipe (3) and a second flange (9) of a second pipe (5) distant from the first flange (7), the first flange (7) extending radially about a reference axis X, the measuring tool (1) being characterized in that it comprises:- a body (13) comprising a measuring support (19), an axial reference stop (21) configured to be in axial abutment against the first flange (7), and a radial reference stop (23) configured to be in radial abutment against the first flange (7),- a first strip (15) slidably mounted radially on the body (13) so that a first slide connection configured to be orthogonal to the reference axis X connects the body (13) and the first strip (15),- a second strip (17) slidably mounted axially on the first strip (15) so that a second slide connection configured to be parallel to the reference axis X connects the first strip (15) and the second strip (17), the second strip (17) including a targeting element (47) and a radial measuring stop (48) configured to be in radial abutment against the second flange (9), the targeting element (47) being configured to allow a user to mark a measuring point on the measuring support (19).

2. The measuring tool (1) according to claim 1, wherein the body (13) comprises a first radial guide rail (37) and wherein the first strip (15) comprises a first slider (39), the first slider (39) being slidably mounted on the first radial guide rail (37) to form the first slide connection.

3. The measuring tool (1) according to claim 2, wherein the first slider (39) carries a guide gib (45).

4. The measuring tool (1) according to any one of claims 1 to 3, wherein the first strip (15) comprises a second axial guide rail (41) and wherein the second strip (17) comprises a second slider (49), the second slider (49) being slidably mounted on the second axial guide rail (41) to form the second slide connection.

5. The measuring tool (1) according to any one of claims 1 to 4, which further comprises a clamping jaw (67), configured to clamp the body (13) on the first flange (7) together with the axial reference stop (21).

6. The measuring tool (1) according to claim 5, wherein the body (13) comprises a third axial guide rail (69), the clamping jaw (67) being slidably mounted axially on the third axialguide rail (69) so that a third slide connection configured to be parallel to the reference axis X connects the clamping jaw (67) and the body (13).

7. The measuring tool (1) according to claim 6, which further comprises an adjustment screw (75), the adjustment screw (75) being configured to adjust and maintain the axial position of the clamping jaw (67) relative to the body (13).

8. The measuring tool (1) according to any one of claims 1 to 7, which includes a first position-holding element (61) configured to hold in position the first strip (15) on the body (13), and a second position-holding element configured to hold in position the second strip (17) on the first strip (15).

9. The measuring tool (1) according to any one of claims 1 to 8, wherein the measuring support (19) is formed by a plate (25) carrying a measurement sheet (27).

10. The measuring tool (1) according to claim 9, wherein the targeting element (47) includes a tangential targeting hole (59) opening out onto the measuring support (19), the tangential targeting hole (59) being configured to allow a user to mark a measuring point on the measurement sheet (27) by means of a measurement marker.

11. A method for measuring relative positioning defects between a first flange (7) of a first pipe (3) and a second flange (9) of a second pipe (5) distant from the first flange (7), the method comprising the following successive steps:- mounting the measuring tool (1) according to any one of claims 1 to 10 on the first flange (7) so that the axial reference stop (21) is in axial abutment against the first flange (7) and the radial reference stop (23) is in radial abutment against the first flange (7),- sliding the first strip (15) relative to the body (13) and the second strip (17) relative to the first strip (15) until the radial measuring stop (48) is in contact with the second flange (9), then holding in position the second strip (17),- marking a measuring point by means of a measuring marker, the measuring point representing a relative positioning defect between the first flange (7) and the second flange (9),- moving the measuring tool (1) angularly about the reference axis X by a predetermined angle, - repeating the previous steps at least two preferably at least three times, until the measuring tool (1) has covered an angular range of at least 90°, preferably at least 180°.18

Images