FR3087889A1 - DEVICE AND METHOD FOR MONITORING THE LIFETIME OF HYDRAULIC EQUIPMENT OF AN AIRCRAFT - Google Patents

Abstract

The invention relates to a device for monitoring the life of at least one hydraulic equipment item of an aircraft subjected to variations in hydraulic pressure (P) in flight, the device comprising an interface for receiving measurement data representative of the hydraulic pressure (P) of the equipment as a function of time (t) in flight, The invention is characterized in that the device comprises a processing device, comprising a means for detecting, from the measurement data, a cycle (CYCEND) of pressure (P) of damaging nature, defined by the fact that the pressure (P), after taking a first prescribed value (P1) of pressure and before taking a second prescribed value (P2) of pressure after the first prescribed value of pressure, is greater than a determined threshold (SEND) of damage , itself greater than the first prescribed value (P1) of pressure and the second prescribed value (P2) of pressure, and a counting means for counting the number of pressure cycles (CYCEND) of a damaging nature.

Description

The invention relates to a device and a method for monitoring the life of at least one hydraulic equipment item of an aircraft subjected to variations in hydraulic pressure in flight.

One field of application of the invention is the maintenance of aircraft, in particular those equipped with turbojets.

In particular, the hydraulic equipment can be a heat exchanger, positioned in the secondary flow as an additional source of cooling for this equipment, in an aircraft turbojet.

Such a heat exchanger is known, for example, from document EP-A-1 916 399.

The object of the invention is to obtain a device and a method for monitoring the life of at least one piece of equipment, making it possible to monitor the fatigue of the hydraulic equipment, in order to be able to carry out preventive maintenance on this equipment.

15 In fact, such preventive maintenance, consisting in monitoring the state of health of the equipment in order to change or repair it sufficiently early, makes it possible to reduce in-flight failures (in English: In-Flight Shut Down), the rate the forced stop on the ground of the aircraft (in English: Aircrat't On Ground) and the rate of cancellation and delay of flights (in English: Delays & Cancellations), this reduction being crucial for the profitability of the company. a turbojet.

To this end, a first object of the invention is a device for monitoring the life of at least one hydraulic equipment item of an aircraft subjected to variations in hydraulic pressure in flight, the device comprising a data reception interface. of measurements representative of the hydraulic pressure of the equipment as a function of the time in flight, characterized in that the device comprises a processing device, comprising a means for detecting, from the measurement data, a pressure cycle of damaging, defined by the fact that the pressure, after taking a first prescribed value of pressure and before taking a second prescribed value of pressure after the first prescribed value of pressure, is greater than a determined threshold of damage, him - even greater than the first prescribed value of pressure and the second prescribed value of pressure, and a 2 counting means for counting the number of pressure cycles n of a damaging nature.

The fatigue wear of the hydraulic equipment of aircraft engines over the hours of operation of the engine is directly linked to the number of cycles they undergo and to the pressure level reached during each cycle.

The invention makes it possible to develop aging predictors, allowing the introduction of means dedicated to predictive maintenance.

The number of damaging pressure cycles P makes it possible to calculate the real lifespan of new equipment coming into operation.

The invention thus enables a statistical verification of the service life observed in service for the hydraulic equipment of the aircraft, a categorization of the aircraft engines fitted with the hydraulic equipment in order to know which are the aircraft fleets and the conditions of use generating the most fatigue cycles of the equipment, and therefore generating the fastest aging of the equipment.

The data on the number of damaging cycles produced by the invention, coupled with information relating to the conditions in which the fleets operate, make it possible to provide estimates as to the aging and the remaining life of the hydraulic equipment, thus allowing the installation of hydraulic equipment. '' predictive maintenance.

20 In the event of quality problems, improper repairs or alterations or the use of parts not guaranteed or supplied by unofficial sources, the statistical knowledge of the rate of aging of the equipment provided by the in-service use of the The invention will further facilitate the demonstration of the deviation of fatigue behavior from the reference parts and the detection of anomalies relating to the service life of an item of equipment.

The invention enables the collection and storage of a very large mass of data relating to the pressure levels actually observed at the level of the hydraulic equipment, which makes it possible to specify as accurately as possible the need for the equipment to be held in future programs.

According to one embodiment of the invention, the monitoring device comprises an estimator for determining the hydraulic pressure of the equipment from values of another hydraulic pressure of another equipment of the aircraft as a function of the time, which are included in the measurement data and which have been measured by a measurement sensor provided on this other equipment.

According to one embodiment of the invention, the processing device comprises an alert means for sending an alert message to the outside, when the number of pressure cycles of a damaging nature on the meter and / or a cumulative number of pressure cycles damaging the meter is greater than or equal to another preset alert threshold.

A second object of the invention is a method for monitoring the life of at least one hydraulic equipment item of an aircraft subjected to variations in hydraulic pressure in flight, a method in which one receives, during a step of reception on a reception interface of measurement data representative of the hydraulic pressure of the equipment as a function of time in flight, characterized in that during a detection step, a processing device is detected, from the measurement data, a damaging pressure cycle, defined by the fact that the pressure, after taking a first prescribed value of pressure and before taking a second prescribed value of pressure after the first prescribed value of pressure , is greater than a determined threshold of damage, itself greater than the first prescribed value of pressure and the second prescribed value of pressure, during a counting step, one counts by the device for treating the number of damaging pressure cycles.

According to one embodiment of the invention, in the event of missing pressure values between the first prescribed value of pressure or the second prescribed value of pressure on the one hand and the pressure detected above the determined threshold of damage, one replaces these missing pressure values by pressure values varying in a linear manner between this first prescribed value of pressure or second prescribed value of pressure on the one hand and the detected pressure, greater than the determined threshold of damage.

4 According to one embodiment of the invention, the measurement data comprise values of another hydraulic pressure of another item of equipment of the aircraft as a function of time, having been measured by a measurement sensor provided on this other equipment before the reception step, the method comprising an estimation step, which is subsequent to the reception step and prior to the detection step and during which it is estimated by an estimator of the processing device, the hydraulic pressure of the equipment from the values of the other hydraulic pressure of the other equipment of the aircraft According to one embodiment of the invention, during a warning step 10 subsequent to the counting step, an alert message is sent to the outside by the processing device, when the number of pressure cycles damaging the meter and / or a cumulative number of pressure cycles damaging the meter is greater than or equal to another predefined alert threshold.

According to one embodiment of the invention, which can be provided for the monitoring device and / or for the monitoring method, the hydraulic equipment comprises a heat exchanger, forming part of a hydraulic circuit for the circulation of a hydraulic fluid of a turbomachine, the hydraulic circuit being positioned in the secondary gas flow of the turbomachine located between a nacelle and a casing of the turbomachine to cool the hydraulic fluid.

According to one embodiment of the invention, which may be provided for the monitoring device and / or for the monitoring method, the determined damage threshold is greater than or equal to 15% of a maximum and nominal hydraulic pressure. of the hydraulic equipment and is less than or equal to 35% of the hydraulic pressure, maximum and nominal.

According to one embodiment of the invention, which can be provided for the monitoring device and / or for the monitoring method, the first prescribed pressure value and the second prescribed pressure value are substantially zero.

The invention will be better understood on reading the description which follows, given solely by way of non-limiting example with reference to the appended drawings, in which: FIG. 1 diagrammatically represents a view in longitudinal section of a example of a turbojet, on which there is the equipment which can be subjected to the device and to the monitoring method according to the invention, FIG. 2 diagrammatically represents an example of a hydraulic circuit 5 for lubricating the turbojet of FIG. 1, comprising the equipment that can be subjected to the device and to the monitoring method according to the invention, FIG. 3 schematically shows a perspective view of an example of the equipment that can be subjected to the device and to the monitoring method according to the invention according to figure 1, 10 - figure 4 is a diagram showing schematically an example of a pressure cycle of damaging nature, which can be detected by the device and the monitoring method according to the invention, FIG. 5 is a diagram showing schematically an example of a pressure cycle which is not detected as being of a damaging nature by the device and the monitoring method according to the invention FIG. 6 represents an example of a flowchart of the monitoring method according to the invention, FIG. 7 diagrammatically represents an example of the monitoring device according to the invention, FIG. 8 diagrammatically represents another item of equipment on which pressure measurements are carried out for the monitoring device and method according to the invention, FIG. 9 is a diagram schematically showing an example of a pressure cycle, in which data is missing, which can be detected by the monitoring device and method according to the invention, and FIG. 10 is a diagram schematically showing an example of a pressure cycle, which can be detected by the monitoring device and method according to the invention and in which missing data has been replaced according to one embodiment of the invention.

In FIGS. 1, 2 and 3, hydraulic equipment of an aircraft subjected to variations in hydraulic pressure in flight and to which the invention can be applied may comprise, for example, a heat exchanger 130, forming part of a hydraulic circuit 100 for circulating a hydraulic fluid used for the in-flight operation of a turbomachine 10 or gas turbine engine assembly 10 of an aircraft such as for example an airplane.

The hydraulic circuit 100 is for example positioned in the bypass duct 40 of the secondary gas flow 52 of the turbomachine 10, located between a nacelle 42 and an external part 44 or casing 44 of the central engine 13 of the turbomachine 10, to cool the engine. hydraulic fluid, and is for example of annular shape.

This example of hydraulic equipment 130 is first described below in more detail with reference to Figures 1, 2 and 3.

In Figure 1, the gas turbine engine assembly 10 has a longitudinal axis 11.

The gas turbine engine assembly 10 includes a fan assembly 12 and a central gas turbine engine 13.

The central gas turbine engine 13 includes a high pressure compressor 14, a combustion chamber 16, and a high pressure turbine 18.

The gas turbine engine assembly 10 may also include a low pressure turbine 20.

Fan assembly 12 includes an array of fan blades 24 extending radially outward from a rotor disc 26.

The engine assembly 10 has an intake side 28 and an exhaust side 30.

The gas turbine engine assembly 10 also includes a plurality of bearing assemblies 20 (not shown in the figures) used to provide rotary and axial support to the blower assembly 12, the high pressure compressor 14, high pressure turbine 18 and to the low pressure turbine 20, for example.

In operation, air flows through the blower assembly 12 and a first portion 50 (primary flow 50) of the air flow is routed through the high pressure compressor 14, in which the air flow is compressed and sent to the combustion chamber 16.

The hot combustion products (not shown in the figures) from the combustion chamber 16 are used to drive the turbines 18 and 20 and thereby produce the thrust of the gas turbine engine assembly 10.

The gas turbine engine assembly 10 also includes a bypass duct 40 which is used to pass a second portion 52 (bypass 52) of the air flow exhausted from the fan assembly 12 around the turbine engine. with 7 central gas 13.

More precisely, the bypass duct 40 extends between an internal wall 201 of a fan fairing 42 or nacelle 42 and an external wall 203 of the separator 44 surrounding the central gas turbine engine 13.

FIG. 2 is a simplified schematic illustration of an exemplary hydraulic circuit 100 for supplying lubricating hydraulic fluid, such as, for example, oil, which may be used in the gas turbine engine assembly 10. of figure 1.

In the exemplary embodiment, the system 100 includes an oil supply source 120, one or more pumps 110 and 112 which circulate the oil through bearings 104, 106, 108 of the central gas turbine engine 13 and in its 10 gears 60 and return the hot oil via the heat exchanger 130 which cools the oil to a lower temperature.

Optionally, the heat exchanger 130 includes an inlet valve 132 and an outlet valve 134 and a bypass valve 136 which can be operated manually or electrically.

In the example shown in Figure 1, the heat exchanger 130 is an air-cooled heat exchanger which is positioned in the bypass duct 40.

The heat exchanger 130 is coupled to the interior wall 201 of the fan shroud 42 between the fan assembly 12 and a fan spacer 150.

In other embodiments not shown, the heat exchanger 130 may be coupled to the inner wall 201, upstream of the fan assembly 12 and downstream of the intake side 28.

As such, the heat exchanger 130 can be positioned anywhere along the axial length of the bypass duct 40 either on the inner side of the fan shroud 42 or on the outer wall 203 of the separator 44.

In Figure 3, on assembly, the heat exchanger 130 is curved such that the heat exchanger assembly 130 has a circumferential and axial profile substantially similar to the circumferential and axial profile of at least a part of the bypass duct 40, for example conforming to the circumferential and axial profile of the inner surface 201 of the fan shroud 42 as shown in FIG. 1 or the outer surface 203 of the separator 44 in other embodiments not shown.

As shown in Figure 3, the heat exchanger 130 covers substantially the entire (about 320 °) circumference.

Alternatively, the heat exchanger 8 may be formed of several segments, which are mounted end to end to cover the same circumferential length.

In Figure 3, the heat exchanger 130 includes a manifold portion 202 extending between a first end 210 and an opposite second end 212.

The manifold portion 202 also includes a radially inner surface 220, a radially outer surface 222, such that the manifold portion 202 has a profile of substantially rectangular axial cross section.

The manifold portion 202 also includes a plurality of cooling fins 230 extending radially inward from the interior surface 220 in the case of Figure 1, to face the bypass 52.

Of course, the fins 230 can be located on the outer surface 222, for example in embodiments where the heat exchanger 130 is mounted on the outer surface 203 of the separator 44 or on the outer surface of the fan shroud 42.

Of course, the fins 230 can be located on both the exterior surface 222 and the interior surface 220.

The manifold portion 202 also contains at least one hydraulic fluid passage channel extending into the manifold portion 202 between its ends 210 and 212.

This hydraulic fluid passage channel is connected to at least one hydraulic fluid inlet connection 240, which is located at the end 210 and which is coupled downstream of the valve 132 (shown in FIG. 2) and to the least one hydraulic fluid outlet connection 242, which is located at end 212 and which is coupled upstream of valve 134 (shown in Figure 2), so that valves 132 and 134 can be operated to circulate the lubricating fluid of the system 100 through the channel of the heat exchanger 130.

The hydraulic fluid circulating in the heat exchanger 130 transfers part of its heat to the part 202 of the collector surrounding the channel, this part 202 of the collector transferring, via the fins 230, part of the heat received to the secondary flow. air passing through the bypass duct 40 or air passing outside the fairing 42.

Embodiments of the device 400 for monitoring the life of hydraulic equipment 9 according to the invention and of the method for monitoring the life of the hydraulic equipment are first described below with reference to Figures 4 to 10. hydraulic equipment according to the invention, having the steps mentioned below.

Of course, the device 400 for monitoring the life of the hydraulic equipment according to the invention and the method for monitoring the life of the hydraulic equipment according to the invention can be applied to any hydraulic equipment of the invention. an aircraft subjected in flight to variations in hydraulic pressure, this equipment possibly being different from the heat exchanger 130 described above and being generally referred to below as hydraulic equipment 130.

As illustrated in Figures 6 and 7, the device 400 for monitoring the life of hydraulic equipment according to the invention and the method for monitoring the life of hydraulic equipment according to the invention are intended for process measurement data 403, which have been acquired during a flight on the aircraft and which are representative of the hydraulic pressure P (for example in the example described above in FIGS. 1 to 3, the pressure P of internal oil of the hydraulic equipment 130) of the hydraulic equipment 130 as a function of time t during this flight, to process these data 403 on the ground after the flight.

The device 400 thus comprises a reception interface 401 for receiving the measurement data 403 (or input data), during a first reception step E1.

The device 400 is configured to implement the method of monitoring the life of the hydraulic equipment.

The device 400 comprises a processing device 402 connected to the reception interface 401.

The device 400 and the lifetime monitoring method are implemented by automatic means.

The processing device 402 and the means described can be implemented by a processor or a computer or a computer or a server, which are provided with computer processing programs for carrying out the treatments described below and with permanent memories for therein. record the measurement data 403 and the processing operations carried out, the interface 401 possibly being an access port thereof.

The processing device 402 comprises a detector 404 for detecting, from the measurement data 403 during a second detection step E2 10 subsequent to the first reception step E1, a cycle CYCEND of the pressure P of a damaging nature. , hereinafter called CYCEND cycle of damaging pressure P or global cycle damaging under pressure.

As illustrated in FIG. 4 showing on the ordinate a curve of pressure P as a function of time t 5 on the abscissa, the damaging pressure P CYCEND cycle is detected by the fact that the pressure P is greater than a determined SEND threshold d 'damage.

The damaging pressure P CYCEND cycle begins at a certain start time Ti with a first prescribed pressure value Pl below the determined damage threshold SEND, then passes above the SEND threshold to have PEND 10 pressure values detected greater than this determined threshold SEND of damage, then passes below the determined threshold SEN] of damage and ends at a certain end instant T2 with a second prescribed value P2 of pressure below the determined SEND threshold of damage.

The determined SEND damage threshold is a configurable fatigue threshold for hydraulic equipment 130 and has been determined beforehand.

The processing device 402 comprises a counter 405 for counting during a third counting step E3 the number NEND of successive CYCEND pressure cycles P damaging in the measurement data 403 received.

FIG. 5 illustrates a case where, during the second detection step E2, the detector 404 does not detect a CYCEND cycle of pressure P damaging in the measurement data 403 between each start time T1 corresponding to the first value prescribed pressure Pl and each end time T2 corresponding to the second prescribed pressure value P2, due to the fact that between these times Ti and T2 the pressure P is not greater than the determined threshold SEND of damage (no 25 values PEND pressure detected).

In this case, no damaging pressure CYCEND cycle P is counted by the counter 405 during the third counting step E3.

The device 400 and the method according to the invention thus provide an estimate of the fatigue undergone by the hydraulic equipment 130 during flight 30 corresponding to the measurement data 403, by quantifying the number of CYCEND cycles at high pressure undergone by this. hydraulic equipment 130 during its operation during this flight.

Thus, the number NEND of CYCEND cycles of damaging pressure P is associated with the flight of the aircraft during which the measurement data 403 and / or 408 were acquired.

According to one embodiment of the invention, the determined SEND threshold of damage is greater than or equal to 15% of a maximum and nominal hydraulic pressure PmAx of the hydraulic equipment and is less than or equal to 35% of the maximum and nominal hydraulic pressure P - MAX The determined SEND threshold of damage can be in particular greater than or equal to 20% of PmAx and less than or equal to 30% of PmAN For example, the determined SEND threshold of damage may be equal at substantially 25% of PmAx.

These threshold values were established from a certification and qualification database linking the number of cycles that can be undergone by the equipment 130 at the level of the pressure in the latter, by noting that pressures lower than this threshold did not cause any fatigue stress.

According to one embodiment of the invention, the method comprises, after counting step E3, a step E6 of updating the cumulative counter 405, during which the number NEND of successive damaging pressure CYCEND cycles P is added, having been counted on the flight in the measurement data 403 received at a previous cumulative value of counter 405, established for 20 previous flights and having been previously recorded in memory, to obtain a new cumulative value of counter 405, it is that is to say a cumulative number NEIN-Drmnn, of successive damaging P pressure CYCENTD cycles over several flights, which is re-recorded in the memory.

According to one embodiment of the invention, the processing device 402 comprises a warning means 418 for transmitting to the outside, during a warning step E8 subsequent to the counting step E3, a AL alert message, when the number NEND of CYCEND cycles of damaging character of the counter 405 and / or the cumulative number NEND-CUMU1. of CYCEND cycles of damaging pressure P is greater than or equal to another predefined warning threshold SA1.

The determined damage threshold SEND, the first prescribed pressure value P1 and the second prescribed pressure value P2 form part of the configuration parameters 12 of the method and of the device 400 and are prerecorded in a memory of the processing device 402.

The number NEND of damaging P pressure CYCEND cycles, having been counted by the counter 405 and / or the cumulative number NEND-cumuluL of successive damaging P pressure CYCEND cycles over 5 several flights is recorded in a memory of the processing device 402, which is updated on each run.

The processing device 402 may include an output interface 406 (which may be a display screen or the like) to supply the outside, during a step E7 with output subsequent to step E3 or E6, as data of output the number NEND of CYCEND cycles of pressure P 10 damaging, having been counted by the counter 405 and / or the cumulative number NEND_ cumul. successive CYCEND cycles of pressure P damaging over several flights and / or the alert message AL and possibly other indicators, such as the determined SEND threshold of damage, the first prescribed value P1 of pressure and the second prescribed value P2 of pressure.

According to one embodiment of the invention, these configuration parameters are predefined as a function of the materials of the hydraulic equipment 130 and of its structure.

These configuration parameters can be set for the same type of hydraulic equipment 130 and / or for the same type of aircraft.

According to one embodiment of the invention, the determined damage threshold Sm can be variable during the life of the equipment 130.

According to one embodiment of the invention, the first prescribed pressure value P 1 and the second prescribed pressure value P2 are substantially zero.

The first prescribed pressure value P1 may correspond to a pressure value of the hydraulic equipment 130 when the turbojet engine is stopped at the start of flight 25 or when the turbojet engine idles shortly after the start of the flight, in which case the first prescribed value P1 pressure is not zero.

The second prescribed pressure value P2 may correspond to a pressure value of the hydraulic equipment 130 when the turbojet engine is stopped at the end of the flight or when the turbojet engine is idling shortly before the end of the flight, in which case the second prescribed value P2 pressure is not zero.

According to one embodiment of the invention, shown in Figures 7 and 8, the hydraulic equipment 130 may not be provided with a pressure sensor to measure its hydraulic pressure P.

In this case, the processing device 402 comprises an estimator 407 for determining, during an estimation step E4 subsequent to the reception step E1 and prior to the detection step E2, the hydraulic pressure P of the equipment 130 from the values 408 of another hydraulic pressure of another equipment 131 of the aircraft as a function of time, which are included in the measurement data 403 and which have been measured by a measurement sensor 133 provided on this other equipment.

This other equipment 131 can for example form part of the same hydraulic circuit 100 as the hydraulic equipment 100 of FIG. 2, the sensor 133 for example making it possible to measure the internal oil pressure of the central engine 13 of the turbomachine 10 and being provided on this engine 13.

The estimator 407 may include a prerecorded hydraulic model or a prerecorded function making it possible to calculate or predict the hydraulic pressure P of the equipment 130 from the values 408 of the other hydraulic pressure of the other equipment 131.

This has the advantage of having no impact on the design, weight, performance or cost of the hydraulic equipment.

In another embodiment of the invention not shown, a hydraulic equipment 130 is provided with a measurement sensor making it possible to directly measure the hydraulic pressure P of the hydraulic equipment 130.

As shown in Figure 9, pressure values P3 may be missing between the start time TI corresponding to the first prescribed pressure value P1 and a detected pressure PEND greater than the determined damage threshold SEND (or in another case, not shown, between a detected pressure PEND greater than the determined damage threshold SEND and the end instant T2 corresponding to the second prescribed pressure value P2).

According to one embodiment of the invention, during a step ES of verifying the data using the detector 404 of the processing device 402, these missing pressure values P3 are replaced by pressure values P4 varying from linearly, for example in the form of a single straight line, between the start time T1 corresponding to the first prescribed pressure value PI and the pressure PEND detected above the determined damage threshold SEND, as is 14 illustrated in FIG. 10 (or in the other aforementioned case, the missing pressure values are replaced by the processing device 402 by pressure values varying in a linear manner, for example in the form of a single straight line , between the pressure detected above the determined damage threshold and the end instant 5 corresponding to the second prescribed pressure value).

According to one embodiment of the invention, the method comprises between the receiving step E1 and the step E2 or E4 the step E5 of verifying the data 403 or 408, for example to detect invalid data, to detect data. and apply methods to replace missing data, 10 as described above with reference to Figures 9 and 10.

The data 403, 408 may include, in addition to the pressure measurements P and the measurements of time t, the serial number of the engine, the number of flights counted by another counter of the turbojet engine, a serial number of the hydraulic equipment monitored. , a history of pressure measurements P.

According to one embodiment of the invention, the method comprises a step of calculating a confidence indicator of the number NEND of successive damaging CYCEND pressure cycles P that have been counted.

This confidence indicator can be calculated as being a numerical value weighted by the quality of the data 403 and / or 408, estimated during step E2 and by the number of missing data.

Of course, the above embodiments, characteristics, possibilities and examples can be combined with each other or be selected independently of each other.

Claims (13)

CLAIMS 1. Device (400) for monitoring the life of at least one hydraulic item of equipment (130) of an aircraft subjected to variations in hydraulic pressure (P) in flight, the device (400) comprising a reception interface (401) of measurement data (403, 408) representative of the hydraulic pressure (P) of the equipment (130) as a function of time (t) in flight, characterized in that the device (400) comprises a device (402) for processing, comprising means (404) for detecting, from the measurement data (403, 408), a cycle (CYCEND) of pressure (P) of damaging nature, defined by the fact that the pressure (P), after having taken a first prescribed value (P1) of pressure and before taking a second prescribed value (P2) of pressure subsequent to the first prescribed value of pressure, is greater than a determined threshold (SEND) of damage, itself greater than the first prescribed value (P1) of pressure and the second prescribed value (P2) of pressure, e t counting means (405) for counting the number (NEND) of damaging pressure cycles (CYCEND). 2. Device according to claim 1, characterized in that it comprises an estimator (407) for determining the hydraulic pressure (P) of the equipment from values of another hydraulic pressure of another equipment (131) of the aircraft as a function of time (t), which are included in the measurement data (408) and which have been measured by a measurement sensor (133) provided on this other equipment (131). 3. Device according to any one of claims 1 and 2, characterized in that the hydraulic equipment comprises a heat exchanger (130), forming part of a hydraulic circuit (100) for circulating a hydraulic fluid from a turbomachine (10), the hydraulic circuit (100) being positioned in the secondary gas flow (52) of the turbomachine located between a nacelle (42) and a casing (44) of the turbomachine (10) for cooling the hydraulic fluid. 30 4. Device according to any one of claims 1 to 3, characterized in that the determined threshold (SEND) of damage is greater than or equal to 15% 16 of a hydraulic pressure, maximum and nominal (PMAX) of the hydraulic equipment and is less than or equal to 35 (1) of the hydraulic pressure, maximum and nominal (PmAx) - 5. Device according to any one of claims 1 to 4, characterized in that the first prescribed value (P1) of pressure and the second prescribed value (P2) of pressure are substantially zero. 6. Device according to any one of claims 1 to 5, characterized in that the processing device (402) comprises an alert means (418) for transmitting an alert message (AL) to the outside, when the number (NEN-D) of 10 cycles (CYCEND) of damaging pressure of the meter (405) and / or a cumulative number (NEND-cumul.) of cycles (CYCEND) of pressure (P) damaging the meter (405) ) is greater than or equal to another predefined alert threshold (SAL). 7. A method of monitoring the life of at least one hydraulic item of equipment (130) of an aircraft subjected to variations in hydraulic pressure (P) in flight, a method in which, during a step ( El) for receiving on an interface (401) for receiving, measurement data (403, 408) representative of the hydraulic pressure (P) of the equipment (130) as a function of time (t) in flight, characterized in that that during a detection step (E2), one detects by a processing device (402) 20, from the measurement data (403, 408), a pressure cycle (CYCEN-D) (P ) of a damaging nature, defined by the fact that the pressure (P), after taking a first prescribed value (Pl) of pressure and before taking a second prescribed value (P2) of pressure after the first prescribed value (P1) pressure, is greater than a determined threshold (SENS) of damage, itself greater than the first prescribed value (PI) of pressure and the d second prescribed pressure value (P2), during a counting step (E3), the processing device (402) counts the number (NEND) of pressure cycles (CYCEND) of a damaging nature. 8. Method according to claim 7, characterized in that in the event of missing pressure values (P3) between the first prescribed value (PI) of pressure or the 17 second prescribed value (P2) of pressure on the one hand and the detected pressure (PEND) greater than the determined damage threshold (SEND), these missing pressure values (P3) are replaced by pressure values (P4) varying in a linear manner between this first prescribed value (P1) pressure or second prescribed pressure value (P2) on the one hand and the detected pressure (PEND). 9. The method of claim 7 or 8, characterized in that the measurement data (408) include values of another hydraulic pressure of another equipment (131) of the aircraft as a function of time (t), having been measured by a measurement sensor (133) provided on this other equipment (131) before step (El) of reception, the method comprising a step (E4) of estimation, which is subsequent to step (E1) reception and prior to the detection step (E2) and during which an estimator (407) of the treatment device (402) is estimated, the hydraulic pressure (P) of the equipment from the values of the other hydraulic pressure of the other equipment (131) of the aircraft 10. A method according to any one of claims 7 to 9, characterized in that the hydraulic equipment comprises a heat exchanger (130), forming part of a hydraulic circuit (100) for circulating a hydraulic fluid from a turbomachine (10), the hydraulic circuit (100) being positioned in the secondary gas flow (52) of the turbomachine located between a nacelle (42) and a casing (44) of the turbomachine (10) for cooling the hydraulic fluid . 11. Method according to any one of claims 7 to 10, characterized in that the determined threshold (SEND) of damage is greater than or equal to 15% of a hydraulic pressure, maximum and nominal (PmAx) of the equipment. 25 hydraulic and is less than or equal to 35% of the hydraulic pressure, maximum and nominal (PmAx). 12. Method according to any one of claims 7 to 11, characterized in that the first prescribed value (Pl) of pressure and the second prescribed value (P2) of pressure are substantially zero. 30 13. A method according to any one of claims 7 to 12, characterized in that, during a step (E8) of warning subsequent to the step (E3) of 18 counting, is sent to the external by the processing device (402), an alert message (AL), when the number (NENE)) of pressure cycles (CYCEND) of damaging nature of the counter (405) and / or a cumulative number (NEND_. cumul) of pressure (P) cycles (CYCEND) damaging the counter (405) is greater than or equal to another predefined alert threshold (Sm).