System and method for measuring a clearance between a rotary vane and a casing of a turbine engine

Abstract

The invention relates to a system (1) for measuring a clearance between a rotary vane and a casing of a turbine engine, the measuring system (1) comprising a removable fastening device (7) provided with a locking mechanism for holding the measuring system (1) in the mounted position on the casing; a retractable stop mechanism (9) provided with a guide (11) and a finger (13) which is configured to hold the rotary vane (3) in a measuring position; a remote acquisition device (15) configured to measure at least one clearance between the rotary vane and the casing when the removable fastening device (7) is in the mounted position and when the retractable stop mechanism (9) is in the deployed position; a plate (17) on which the removable fastening device (7), the retractable stop mechanism (9) and the remote acquisition device (15) are attached.

Description

[0001] DESCRIPTION

[0002] TITLE: System and method for measuring a clearance between a rotating blade and a casing of a turbomachine

[0003] Field of invention

[0004] The present invention relates to a system for measuring a clearance between a rotating blade and a casing of a turbomachine. In particular, the measuring system is suitable for fan blades whose main function is to bring the incoming air to a certain compression level.

[0005] Prior art

[0006] It is known to check the correct dimensioning of the clearance between a rotating blade and a casing to ensure the conformity of the turbomachine. Typically, for a fan blade, the clearance must correspond to the hundredth of a millimeter to the value planned during design.

[0007] Too much clearance can negatively impact engine operability and performance. Conversely, too little clearance can cause wear and mechanical contact between the rotating blade and the casing.

[0008] One possibility for measuring the correct clearance size is to use shims of known thicknesses that are manually slid between the rotating blade and the casing. This is satisfactory in that the correct size can be easily determined.

[0009] However, this type of measurement has drawbacks. For the operator responsible for carrying out the measurements, it can be long and tedious to insert the shim in the desired locations, as several blades at different time positions must be tested. The operator also has the constraint of limiting the friction of the shim to avoid damaging the rotating blade or the casing.

[0010] This manual measurement also raises the question of the quality of the measurement because it is likely to fluctuate depending on the circumstances, particularly if the operator engages the shim beyond the axial measurement position. By axial, it is understood relative to the rotating axis of the turbomachine.

[0011] Thus, although it is possible to measure the clearance, there remains a problem of repeatability and reproducibility of the measurements. The present invention aims to solve all or part of the drawbacks mentioned above.

[0012] Statement of the invention

[0013] To this end, the present invention relates to a system for measuring a clearance between a rotating blade and a casing of a turbomachine, the measuring system comprising: a removable fixing device shaped to fit by shape cooperation to a complementary location of the casing in a mounted position, the removable fixing device being provided with a locking mechanism for maintaining the mounted position of the measuring system on the casing, a retractable stop mechanism provided with a guide and a finger capable of being arranged relative to the guide in a deployed position in which the finger is configured to maintain the rotating blade in a measuring position, a remote acquisition device configured to measure at least one clearance between the rotating blade and the casing when the removable fixing device is in the mounted position and the retractable stop mechanism in the deployed position,a plate on which the removable fixing device, the retractable stop mechanism and the remote acquisition device are attached.,

[0014] Thus, the measuring system is a specific tool with a device for remote acquisition of a measurement which can be removably fixed on the casing and lock the rotating blade in the measuring position.

[0015] For the operator, the installation in the mounted position of the measuring system is quick and easy. The positioning of the rotating blade is also simple to achieve since the measuring position is reached by a stop on the finger.

[0016] Furthermore, acquiring the measurement remotely eliminates the risk of scratches or damage to the rotating blade or casing.

[0017] The precise two-step positioning of the measuring system - mounted position then measuring position - ensures good reproducibility and repeatability of clearance measurements.

[0018] According to one aspect of the invention, the remote acquisition device comprises at least one sensor configured to measure a clearance corresponding to a minimum distance between the rotating blade and the casing in a corresponding measurement plane of the sensor. In other words, the sensor is configured to detect in the measurement plane a point on the rotating blade and a point on the casing having the smallest distance and then to measure this distance.

[0019] This type of measurement is advantageous because it is non-intrusive and avoids any scratching or damage to the rotating blade and / or casing.

[0020] According to one aspect of the invention, the measuring system comprises at least one device for adjusting the relative position of the at least one sensor relative to the plate so as to define the positioning of the corresponding measuring plane of the sensor relative to the plate.

[0021] This arrangement contributes to the reliability of the clearance measurement by the sensor because the measurement plane can be precisely defined to correspond to the exact desired measurement location between the rotating blade and the casing.

[0022] According to one aspect of the invention, the at least one measuring plane is positioned so as to be transverse and in particular normal to the casing at the location of the measured clearance.

[0023] According to one aspect of the invention, the adjustment device comprises a support configured to receive the corresponding sensor, the support being provided with an adjustment pin whose movement makes it possible to modify the position of the sensor relative to the plate.

[0024] Preferably, the adjustment device comprises a clamping element for maintaining the relative position of the support with respect to the plate. In particular, the clamping element comprises two screws configured to cooperate with two corresponding threads of the support. The screws are configured to extend through at least one through opening of the plate to ensure the support is secured to the plate.

[0025] According to one aspect of the invention, the remote acquisition device comprises three sensors configured to measure three clearances corresponding to three minimum distances between the rotating blade and the casing in three corresponding measurement planes.

[0026] Three measuring planes are thus defined to measure three clearances at three different locations between the rotating blade and the casing. These three measurements are quick and reliable. Furthermore, no handling is required by the operator once the measuring system is in the mounted and measuring position. Each sensor is associated with a corresponding adjustment device for the measuring system. The sensors are arranged so that the three measuring planes are approximately parallel.

[0027] According to one aspect of the invention, the at least one sensor is a laser profilometer adapted to identify two distinct elements and to measure a length of a gap separating said two elements.

[0028] The measuring system is particularly effective when using one or more laser profilometers as a sensor. This type of sensor allows a length to be measured remotely by sending a laser beam and receiving a return from said laser beam.

[0029] According to one aspect of the invention, the finger is further adapted to be disposed relative to the guide in a retracted position in which the finger is outside the rotational path of the rotating blade when the measuring system is in the mounted position.

[0030] This arrangement allows multiple clearance measurements to be taken on several rotating blades without having to move the measuring system from the mounted position. This saves time when taking the measurements required to inspect rotating blades.

[0031] According to one aspect of the invention, the retractable stop mechanism comprises a biasing element configured to automatically move the finger from the retracted position to the extended position.

[0032] In addition, the retractable stop mechanism includes an actuating handle for manually moving the finger from the extended to the retracted position. This means that it is sufficient to pull the actuating handle when changing the rotating blade.

[0033] According to one aspect of the invention, the removable fixing device is a fixing flange adapted to be removably fixed to a receiving flange of the casing. In particular, the receiving flange is located at a lower location of the casing directly above an axis of rotation of the rotating blade.

[0034] This position corresponds to the six o'clock position.

[0035] Preferably, the mounting flange comprises two rods adapted to engage in two corresponding holes in the housing in the mounted position. Since only one location in the mounted position is provided, it is easy for the operator to arrange the measuring system in the mounted position.

[0036] The locking mechanism comprises two rotary levers capable of being arranged in a locked position for holding the fixing flange on the casing. According to one aspect of the invention, the three measuring planes have a direction inclined relative to a vertical plane passing through the axis of rotation of the rotating blade.

[0037] This arrangement facilitates measurement since the rotating blade extends at an angle to the axis of rotation. The three measuring planes are thus suitable for measuring three clearances along the rotating blade.

[0038] According to one aspect of the invention, the guide and the finger of the retractable stop mechanism also extend at an inclination substantially identical to that of the measuring planes relative to the axis of rotation. The measuring system is thus adapted to the inclined profile of the rotating blade.

[0039] According to one aspect of the invention, the plate extends in the mounted position along a mounting axis substantially parallel to the axis of rotation of the rotating blade. Preferably, the three sensors are oriented inclined relative to the mounting axis.

[0040] A recess in the plate allows at least one of the sensors to be mounted recessed along the mounting axis so as to allow rotation of the rotating blade when the finger of the retractable stop mechanism is in the retracted position.

[0041] According to one aspect of the invention, the measurement system comprises a data analysis terminal, such as a computer on a mobile cart, and a transmission cable capable of connecting the remote acquisition device to the data analysis terminal.

[0042] Therefore, the raw data obtained by the sensors are processed to obtain the three sets per rotating blade and for several rotating blades.

[0043] According to one aspect of the invention, the measuring system can be configured to measure at least one positioning, for example to detect a good positioning, of at least one platform 130 of the turbomachine, for example intended to be mounted in an interval which extends circumferentially between two adjacent rotating blades, for example the good positioning of the at least one platform of the turbomachine mounted in an interval which extends circumferentially between two adjacent rotating blades.

[0044] Preferably, between two blades, for example two rotating blades, for example on the side of the roots of said two blades, for example rotating, adjacent, for example at or near the roots, for example in order to delimit, for example on the inner or central side, an annular gas circulation vein, the vein being delimited, for example on the outer or peripheral side, by a corresponding casing portion of the turbomachine.

[0045] According to one aspect of the invention, the system comprises a detector configured to measure said positioning, for example to detect said correct positioning, of the at least one platform of the turbomachine. Preferably, the detector is attached to the plate.

[0046] It is advantageous to take advantage of the platform and the measurements already taken to also check the correct positioning of the platforms.

[0047] The present invention also relates to an intermediate production assembly comprising a casing, a rotating wheel, preferably a fan blade, and a measuring system as described above.

[0048] The present invention also relates to a method for measuring at least one clearance between a rotating blade and a casing of a turbomachine, the rotating blade having an end surface facing an abradable material of the casing covering an inner part of the casing, the measuring method comprising the following steps: providing a measuring system as described above, adapting by shape cooperation to the complementary location of the casing the measuring system in the mounted position, then locking the removable fixing device in the mounted position on the casing with the locking mechanism, moving the blading comprising the rotating blade around the axis of rotation of the blading relative to the casing to bring the rotating blade into abutment on a dedicated surface of the finger when the finger is in the deployed position so as to maintain the rotating blade in the measuring position,measure at least one clearance between the rotating blade in the measuring position and the abradable material of the casing with the remote acquisition device.,

[0049] According to one aspect of the invention, following the step of adaptation by form cooperation, the following steps can be carried out optionally if necessary: ​​moving a blade around the axis of rotation to bring the rotating blade into the measurement position or close to the measurement position, if necessary by arranging the finger of the retractable stop mechanism in the retracted position, arranging or ensuring that the finger of the retractable stop mechanism is in the deployed position. Preferably, following the measurement the method comprises a step of recording the at least one measurement of the at least one clearance on a memory of the measurement system.

[0050] Carrying out the measurement process is easy and involves setting up the measurement system properly so that the remote acquisition device can accurately measure at least one game.

[0051] The removable fixing device and the retractable stop mechanism allow in particular to obtain excellent reproducibility and repeatability of the measurements taken since the relative position of the casing, the rotating blade and the remote acquisition device are strictly identical at each installation and measurement with the measuring system.

[0052] In practice, the measurement process is quick to carry out by the operator responsible for measuring at least one clearance and the results obtained are reliable.

[0053] According to one aspect of the invention, following the step of measuring at least one clearance between the rotating blade and the abradable material of the casing, the method comprises the following additional steps: placing the finger of the retractable stop mechanism in the retracted position, then moving the blade around the axis of rotation to bring an additional rotating blade into the measurement position or close to the measurement position, placing the finger of the retractable stop mechanism in the deployed position, then placing the additional rotating blade in abutment on the dedicated surface of the finger when the finger is in the deployed position so as to maintain the additional rotating blade in the measurement position, measuring at least one additional clearance between the additional rotating blade in the measurement position and the abradable material of the casing with the remote acquisition device, recording the measurement of the at least one additional clearance on the memory of the measurement system.

[0054] Advantageously, the measuring system can remain in the mounted position when a measurement of at least one clearance is to be carried out on an additional rotating blade.

[0055] It is sufficient to place the finger of the retractable stop mechanism in the retracted position to allow rotation of the blade and to place the additional rotating blade in the measuring position or close to the measuring position. By the expression "close to" it is understood that the additional rotating blade is brought to a location allowing deployment of the finger and then an additional rotation of the additional rotating blade allows the latter to be brought into abutment against the finger.

[0056] According to one aspect of the invention, the additional steps are repeated a number of times corresponding to a number of additional rotating blades to be measured.

[0057] According to one aspect of the invention, the measuring method comprises a prior step consisting of measuring relief disparities of an internal portion of the abradable material intended to be opposite the blading.

[0058] This arrangement allows for 360° knowledge of irregularities in the internal portion of the abradable material. Indeed, it is preferable to know the indentations or bumps in the abradable material likely to modify the clearance between the rotating blade and the casing depending on the clockwise position of the rotating blade.

[0059] According to one aspect of the invention, the measurement of the disparities is carried out by a regularity control device comprising a base capable of being mounted on a turbomachine rotor intended to receive the blading.

[0060] The assembly of the regularity control device is carried out in the absence of the blading, in particular before the assembly of the blading during manufacturing.

[0061] The regularity control device is thus able to move around the axis of rotation and further comprises at least one comparator intended to measure by contact a relief of the abradable material, the comparator being able to determine a dimension of the relief as well as a time position of the relief.

[0062] Preferably, the regularity control device comprises three comparators axially spaced along the axis of rotation.

[0063] According to one aspect of the invention, the measurements of the relief disparities are taken into account to determine, from the clearance measurements made by the measurement system, an actual minimum clearance for each rotating blade concerned.

[0064] Preferably, a calculation-determined rotor deflection is also taken into account.

[0065] Thus, the measuring system and method presented above are advantageous in that only one measurement at a six o'clock position is necessary to determine at least a minimum clearance of a rotating blade.

[0066] The different aspects defined above, which are not incompatible, can be combined. Brief description of the figures

[0067] The invention will be better understood with the aid of the detailed description which is set out below with reference to the accompanying drawings.

[0068] [Fig. 1] is a top view of a measuring system.

[0069] [Fig. 2] is a rear view of the measuring system.

[0070] [Fig. 3] is a perspective view of the measuring system.

[0071] [Fig. 4] is a rear perspective view of the measuring system mounted on a turbomachine casing.

[0072] [Fig. 5] is a detailed perspective view of the housing-mounted measuring system and a blading assembly comprising a rotating vane.

[0073] [Fig. 6] is a schematic view of the measuring system and a portion of the turbomachine including the casing and the blading.

[0074] [Fig. 7] is a diagram representing the steps of a measurement process.

[0075] [Fig. 8] is a side view of a regularity control device.

[0076] [Fig. 9] is a rear perspective view of the measuring system mounted on a turbomachine casing, the measuring system being configured to measure at least one positioning of at least one platform of the turbomachine.

[0077] [Fig. 10] is a diagram representing the steps of a measurement process.

[0078] Description with reference to figures

[0079] In the detailed description which follows of the figures defined above, the same elements or elements fulfilling identical functions may retain the same references so as to simplify the understanding of the invention.

[0080] As illustrated in Figures 1 to 6, a system 1 for measuring a clearance between a rotating blade 3 and a casing 5 of a turbomachine comprises a removable fixing device 7 shaped to adapt by shape cooperation to a complementary location of the casing 5 in a mounted position.

[0081] The removable fixing device 7 is provided with a locking mechanism for maintaining the mounted position of the measuring system 1 on the housing 5.

[0082] The measuring system 1 comprises a retractable stop mechanism 9 provided with a guide 11 and a finger 13 capable of being arranged relative to the guide 11 in a deployed position in which the finger 13 is configured to hold the rotating blade 3 in a measuring position as illustrated in FIG. 5.

[0083] The measuring system 1 comprises a remote acquisition device 15 configured to measure at least one clearance between the rotating blade 3 and the casing 5 when the removable fixing device 7 is in the mounted position and the retractable stop mechanism 9 in the deployed position.

[0084] The measuring system 1 also comprises a plate 17 on which the removable fixing device 7, the retractable stop mechanism 9 and the remote acquisition device 15 are attached.

[0085] Thus, the measuring system 1 is a specific tool with a remote acquisition device 15 for a measurement which can be removably fixed to the casing 5 and lock the rotating blade 3 in the measuring position.

[0086] The remote acquisition device 15 comprises at least one sensor 19 configured to measure a clearance corresponding to a minimum distance between the rotating blade 3 and the casing 5 in a corresponding measurement plane 21 of the sensor 19. Here, the remote acquisition device 15 comprises three sensors 19.

[0087] In other words, each sensor 19 is configured to detect in the corresponding measuring plane 21 a point on the rotating blade 3 and a point on the casing 5 having the smallest distance and then to measure this distance.

[0088] The measuring system 1 comprises, for each sensor 19, a corresponding adjustment device 23 for the relative position of the sensor 19 with respect to the plate 17 so as to define the positioning of the corresponding measuring plane 21 of the sensor 19 with respect to the plate 17.

[0089] As illustrated in Figure 5, each measuring plane 21 is positioned so as to be transverse and in particular normal to the casing 5 at the location of the measured clearance.

[0090] Each adjustment device 23 comprises a support 25 configured to receive the corresponding sensor 19, the support 25 being provided with an adjustment pin T1, the movement of which makes it possible to modify the position of the sensor 19 relative to the plate 17.

[0091] Each adjustment device 23 comprises a clamping element 29 for maintaining the relative position of the support 25 with respect to the plate 17. In particular, the clamping element 29 comprises two screws configured to cooperate with two corresponding threads of the support 25. As illustrated in FIG. 5, the screws are configured to extend through at least one through opening 31 of the plate 17 to ensure the securing of the support 25 to the plate 17.

[0092] Here, the remote acquisition device 15 comprises three sensors 19 configured to measure three clearances corresponding to three minimum distances between the rotating blade 3 and the casing 5 in three corresponding measurement planes 21.

[0093] The sensors 19 are arranged so that the three measuring planes 21 are substantially parallel.

[0094] Each sensor 19 is a laser profilometer adapted to identify two distinct elements and to measure a length of a gap separating said two elements. This type of sensor makes it possible to measure a length remotely by sending a laser beam and receiving a return from said laser beam.

[0095] With respect to the retractable stop mechanism 9, the finger 13 is further adapted to be arranged relative to the guide 11 in a retracted position in which the finger 13 is outside the rotary path of the rotating blade 3 when the measuring system 1 is in the mounted position.

[0096] The retractable stop mechanism 9 comprises a return element configured to automatically move the finger 13 from the retracted position to the extended position.

[0097] Furthermore, the retractable stop mechanism 9 comprises an actuating handle 33 for manually moving the finger 13 from the extended position to the retracted position. It is thus sufficient to pull the actuating handle 33 when changing the rotating blade 3.

[0098] The removable fixing device 7 is a fixing flange adapted to be removably fixed to a receiving flange of the casing 5. In particular, the receiving flange is located at a lower location of the casing 5 directly above an axis of rotation 35 of the rotating blade 3. This position corresponds to the six o'clock position.

[0099] The mounting flange comprises two rods 37 adapted to engage in two corresponding holes of the casing 5 in the mounted position. Since only one location in the mounted position is provided, it is easy for the operator to arrange the measuring system 1 in the mounted position.

[0100] The locking mechanism comprises two rotary levers 39 capable of being arranged in a locked position for holding the fixing flange on the casing 5. The three measuring planes 21 have a direction inclined relative to a vertical plane passing through the axis of rotation 35 of the rotating blade 3. This arrangement facilitates the measurement since the rotating blade 3 extends in an inclined manner relative to the axis of rotation 35.

[0101] The guide 11 and the finger 13 of the retractable stop mechanism 9 also extend at an inclination substantially identical to that of the measuring planes 21 relative to the axis of rotation 35. The measuring system 1 is thus adapted to the inclined profile of the rotating blade 3.

[0102] The plate 17 extends in the mounted position along a mounting axis 41 substantially parallel to the axis of rotation 35 of the rotating blade 3. The three sensors 19 are oriented in an inclined manner relative to the mounting axis 41.

[0103] A recess 43 of the plate 17 makes it possible to mount one of the sensors 19 set back along the mounting axis 41 so as to allow rotation of the rotating blade 3 when the finger 13 of the retractable stop mechanism 9 is in the retracted position.

[0104] As illustrated in Figure 6, the measurement system 1 comprises a data analysis terminal 45, such as a computer on a mobile cart, and a transmission cable 47 capable of connecting the remote acquisition device 15 to the data analysis terminal 45.

[0105] Therefore, the raw data obtained by the sensors 19 are processed so as to obtain the three sets per rotating blade 3 and for several rotating blades 3.

[0106] As illustrated in Figure 9, the measuring system 1 can be configured to measure at least one positioning, for example to detect a good positioning, of at least one platform of the turbomachine, for example intended to be mounted in an interval which extends circumferentially between two adjacent rotating blades 3, for example the good positioning of the at least one platform of the turbomachine mounted in an interval which extends circumferentially between two adjacent rotating blades 3.

[0107] Each platform is for example positioned between two blades, for example two rotating blades, for example on the side of the roots of said two blades, for example rotating, 3 adjacent, for example at or near the roots, for example in order to delimit, for example on the inner or central side, an annular gas circulation vein, the vein being delimited, for example on the outer or peripheral side, by a corresponding casing portion of the turbomachine. The system may for example comprise a detector 100 configured to measure said positioning, for example to detect said correct positioning, of the at least one platform of the turbomachine.

[0108] For example, alternatively or in combination with being configured to measure at least one clearance between the rotating blade 3 and the casing 5, the remote acquisition device 15 can be configured to measure said positioning, for example to detect said correct positioning, of the at least one platform of the turbomachine.

[0109] The remote acquisition device 15 may comprise the detector 100. Alternatively, the detector 100 may be separate from the remote acquisition device 15.

[0110] The detector 100 may comprise or be at least one sensor 190, for example a sensor 190 additional to the sensor(s) 19, for example a fourth sensor 190.

[0111] The detector 100 may be a position detector. The sensor 190 may be a position sensor 190, for example a laser sensor.

[0112] The detector 100 can be attached to the plate 17. It is advantageous to take advantage of the plate 17 and the measurements already taken to also check the correct positioning of the platforms.

[0113] The detector 100 may be attached to the plate on the side opposite at least one, for example the sensor(s) 19. The detector 100 may be attached to the plate on the same side as the retractable stop mechanism 9. The detector 100 may be attached to a plate of the plate extending in the mounted position along the mounting axis 41. The plate has for example a width and a length. The detector 100 is for example located on one side of the plate in the width direction, for example a side opposite a side from which the recess 43 extends. The detector 100 is for example located on a central zone of the plate in the length direction, for example relatively to the retractable stop mechanism 9 arranged on one side in the length direction. The detector is for example arranged at the same level as the or one of the sensor(s) 19, on an opposite side of the plate with respect to said sensor 19.

[0114] The detector 100 may comprise a sensor support 170, for example allowing the sensor 190 to be positioned relative to the plate 17. The sensor support 170 is for example an inclined support for positioning the sensor 190 in an inclined manner. The sensor support 170 comprises for example an inclined ramp. The sensor support 170 may be fixed to the plate 17, for example by means of screws.

[0115] The detector 100 may be configured to measure the positioning of the at least one platform of the turbomachine, for example a relative position of the platform, for example of one or more walls of the platform, for example relative to one and / or the other of the adjacent blades, for example when the removable fixing device 7 is in the mounted position and the retractable stop mechanism (9) in the deployed position.

[0116] Figure 6 schematically represents an intermediate production assembly 49 comprising a casing 5, a rotating wheel, preferably a fan blade comprising a plurality of rotating blades 3, and a measuring system 1 as described above.

[0117] Figure 7 represents a method for measuring at least one clearance between a rotating blade 3 and a casing 5 of a turbomachine, the rotating blade 3 having an end surface 51 facing an abradable material 53 of the casing 5 covering an interior part of the casing 5.

[0118] One step El is to have a measuring system 1 as described above.

[0119] A step E2 consists of adapting by shape cooperation to the complementary location of the casing 5 the measuring system 1 in the mounted position, then locking the removable fixing device 7 in the mounted position on the casing 5 with the locking mechanism.

[0120] A step E2', carried out optionally if necessary, consists of moving the blading around the rotation axis 35 to bring the rotating blade 3 into the measuring position or close to the measuring position, if necessary by placing the finger 13 of the retractable stop mechanism 9 in the retracted position.

[0121] A step E2'', carried out optionally if necessary, consists of arranging or ensuring that the finger 13 of the retractable stop mechanism 9 is in the deployed position.

[0122] A step E3 consists of moving the blading comprising the rotating blade 3 around an axis of rotation 35 of the blading relative to the casing 5 to bring the rotating blade 3 into abutment on a dedicated surface of the finger 13 when the finger 13 is in the deployed position so as to maintain the rotating blade 3 in the measurement position.

[0123] A step E4 consists of measuring at least one clearance between the rotating blade 3 in the measurement position and the abradable material 53 of the casing 5 with the remote acquisition device 15. A step E4' consists of recording the at least one measurement of the at least one clearance on a memory of the measurement system 1. This memory is included in the data analysis terminal 45.

[0124] Following the step E4 of measuring at least one clearance between the rotating blade 3 and the abradable material 53 of the casing 5, the method may comprise the additional steps described below.

[0125] A step E5 consists of placing the finger 13 of the retractable stop mechanism 9 in the retracted position.

[0126] A step E6 then consists of moving the blading around the rotation axis 35 to bring an additional rotating blade 3' into the measurement position or close to the measurement position,

[0127] A step E7 consists of placing the finger 13 of the retractable stop mechanism 9 in the deployed position.

[0128] A step E8 consists of placing the additional rotating blade 3' in abutment on the dedicated surface of the finger 13 when the finger 13 is in the deployed position so as to maintain the additional rotating blade 3' in the measurement position.

[0129] A step E9 consists of measuring at least one additional clearance between the additional rotating blade s' in the measuring position and the abradable material 53 of the casing 5 with the remote acquisition device 15.

[0130] A step E10 consists of recording the measurement of the at least one additional set on the memory of the measurement system 1.

[0131] Advantageously, the measuring system 1 can remain in the mounted position when a measurement of at least one clearance must be carried out on the additional rotating blade 3'.

[0132] It is sufficient to place the finger 13 of the retractable stop mechanism 9 in the retracted position to allow rotation of the blade and to place the additional rotating blade 3' in the measuring position or close to the measuring position.

[0133] By the expression "in proximity", it is understood that the additional rotating blade 3' is brought to a location allowing the deployment of the finger 13 then an additional rotation of the additional rotating blade 3' makes it possible to bring the latter into abutment against the finger 13.

[0134] The additional steps E5 to E10 are repeated a number of times corresponding to a number of additional rotating blades 3' to be measured. Furthermore, the measuring method may also comprise a prior step E0 consisting of measuring relief disparities of an internal portion of the abradable material 53 intended to be opposite the blading.

[0135] This arrangement makes it possible to know over 360° the irregularities of the internal portion of the abradable material 53. Indeed, it is preferable to know the recesses or bumps of the abradable material 53 likely to modify the clearance between the rotating blade 3 and the casing 5 according to the clockwise position of the rotating blade 3.

[0136] As illustrated in Figure 8, the measurement of the disparities is carried out by a regularity control device 55 comprising a base 57 capable of being mounted on a turbomachine rotor intended to receive the blading.

[0137] The assembly of the regularity control device 55 is carried out in the absence of the blading, in particular before the assembly of the blading during manufacturing.

[0138] The regularity control device 55 is thus able to move around the rotation axis 35 and further comprises at least one comparator 59 intended to measure by contact a relief of the abradable material 53, the comparator 59 being able to determine a dimension of the relief as well as a time position of the relief.

[0139] Here, the regularity control device 55 comprises three comparators 59 axially spaced along the axis of rotation 35.

[0140] The measurements of the relief disparities are taken into account to determine, from the clearance measurements made by the measuring system 1, a real minimum clearance for each rotating blade 3 concerned.

[0141] Preferably, a calculation-determined rotor deflection is also taken into account.

[0142] Thus, the measuring system and method presented above are advantageous in the sense that only one measurement at a six o'clock position is necessary to determine at least a minimum clearance of a rotating blade 3.

[0143] For the operator, the installation in the mounted position of the measuring system 1 is easy and quick. The positioning of the rotating blade 3 is also simple to achieve since the measuring position is reached by a stop on the finger 13.

[0144] Furthermore, the acquisition of the remote measurement eliminates the risks of scratches or damage to the rotating blade 3 or the casing 5.

[0145] As illustrated in Figure 10, additional or alternative steps may be added in the case where the system is configured to measure at least one positioning of at least one turbomachine platform.

[0146] Alternatively or in addition to step(s) E4, and / or E4', the method may comprise step(s) E4bis, and / or E4'bis. A step E4bis may consist of measuring the at least one positioning of the platform of the turbomachine adjacent to the blade in the measurement position with the detector, for example with the remote acquisition device 15.

[0147] A step E4'bis may consist of recording the at least one measurement of the at least one positioning on the memory of the measurement system 1.

[0148] Alternatively or in addition to step(s) E9, and / or E10, the method may comprise step(s) E9bis, and / or E10bis.

[0149] A step E9bis may consist of measuring at least one additional positioning of the platform of the turbomachine adjacent to the blade in the measurement position with the remote acquisition device 15.

[0150] An ElObis step consists of recording the measurement of at least one additional positioning on the memory of the measuring system 1.

[0151] Advantageously, the measuring system 1 can remain in the mounted position when a measurement of at least one positioning must be carried out on the platform adjacent to the additional rotating blade 3'.

[0152] In combination with steps E5 to E8, and for example steps E9 and E10, the additional steps E9bis and E10 are repeated a number of times corresponding to a number of additional platforms to be measured.

[0153] As goes without saying, the invention is not limited to the single embodiment described above as an example; on the contrary, it encompasses all variant embodiments.

Claims

CLAIMS 1. Measuring system (1) of a clearance between a rotating blade (3) and a casing (5) of a turbomachine, the measuring system (1) comprising: a removable fixing device (7) shaped to adapt by shape cooperation to a complementary location of the casing (5) in a mounted position, the removable fixing device (7) being provided with a locking mechanism for maintaining the mounted position of the measuring system (1) on the casing (5), a retractable stop mechanism (9) provided with a guide (11) and a finger (13) capable of being arranged relative to the guide (11) in a deployed position in which the finger (13) is configured to maintain the rotating blade (3) in a measuring position, a remote acquisition device (15) configured to measure at least one clearance between the rotating blade (3) and the casing (5) when the removable fixing device (7) is in the mounted position and the retractable stop mechanism (9) in the deployed position deployed,a plate (17) on which the removable fixing device (7), the retractable stop mechanism (9) and the remote acquisition device (15) are attached., 2. Measuring system (1) according to claim 1, wherein the remote acquisition device (15) comprises at least one sensor (19) configured to measure a clearance corresponding to a minimum distance between the rotating blade (3) and the casing (5) in a corresponding measuring plane (21) of the sensor (19).

3. Measuring system (1) according to claim 2, comprising at least one device (23) for adjusting the relative position of the at least one sensor (19) relative to the plate (17) so as to define the positioning of the corresponding measuring plane (21) of the sensor (19) relative to the plate (17).

4. Measuring system (1) according to one of claims 2 or 3, wherein the remote acquisition device (15) comprises three sensors (19) configured to measure three clearances corresponding to three minimum distances between the rotating blade (3) and the casing (5) in three corresponding measuring planes (21).

5. Measuring system (1) according to one of claims 2 to 4, in which the at least one sensor (19) is a laser profilometer adapted to identify two distinct elements and to measure a length of a gap separating said two elements.

6. Measuring system (1) according to one of claims 1 to 5, wherein the finger (13) is further adapted to be arranged relative to the guide (11) in a retracted position in which the finger (13) is outside the rotary path of the rotating blade (3) when the measuring system (1) is in the mounted position.

7. Measuring system (1) according to one of claims 1 to 6, in which the removable fixing device (7) is a fixing flange adapted to be fixed in a removably manner to a receiving flange of the casing (5).

8. Method for measuring at least one clearance between a rotating blade (3) and a casing (5) of a turbomachine, the rotating blade (3) having an end surface (51) facing an abradable material (53) of the casing (5) covering an interior part of the casing (5), the measuring method comprising the following steps: (El) having a measuring system (1) according to one of claims 1 to 7, (E2) adapting the measuring system (1) in the mounted position to the complementary location of the housing (5) by means of form cooperation, then locking the removable fixing device (7) in the mounted position on the housing (5) with the locking mechanism, (E3) moving the blading comprising the rotating blade (3) around the axis of rotation (35) of the blading relative to the casing (5) to bring the rotating blade (3) into abutment on a dedicated surface of the finger (13) when the finger (13) is in the deployed position so as to maintain the rotating blade (3) in the measuring position, (E4) measuring at least one clearance between the rotating blade (3) in the measuring position and the abradable material (53) of the casing (5) with the remote acquisition device (15).

9. Measuring method according to claim 8, in which, following the step (E4) of measuring at least one clearance between the rotating blade (3) and the abradable material (53) of the casing (5), the method comprises the following additional steps: (E5) place the finger (13) of the retractable stop mechanism (9) in the retracted position, then, (E6) moving the blade around the rotation axis (35) to bring an additional rotating blade (3') into the measuring position or close to the measuring position, (E7) place the finger (13) of the retractable stop mechanism (9) in the deployed position, then, (E8) placing the additional rotating blade (3') in abutment on the dedicated surface of the finger (13) when the finger (13) is in the deployed position so as to maintain the additional rotating blade (3') in the measuring position, (E9) measuring at least one additional clearance between the additional rotating blade (3') in the measuring position and the abradable material (53) of the casing (5) with the remote acquisition device (15), (E10) record the measurement of the at least one additional set on the memory of the measuring system (1).

10. Measuring method according to one of claims 8 or 9, comprising a prior step (E0) consisting of measuring relief disparities of an internal portion of the abradable material (53) intended to be opposite the blading.

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