Device for testing blades of turbine apparatus

FIELD: testing engineering.

SUBSTANCE: device comprises high-frequency generator and inductor connected in series, device for control of heating, system for air supply, device for external cooling, measuring system, unit of contact temperature gauges, and device for bottom clamping connected with the end section of the blade. The device is provided with a means for axial loading, device for top clamping connected with the shelf of the end section of the blade, device for control of axial loading, first dynamometer, device for applying torque, which has the second dynamometer, device for information input, load-bearing frame, contactless temperature gauge, generator of nonstandard signals, oil pumping system, and device for internal cooling.

EFFECT: enhanced reliability of testing.

7 cl, 1 dwg

 

The invention relates to plants and stands for research and testing of blades for gas turbine engines (GTE), facilities and other turbomachines on thermomechanical fatigue with playback of cyclic thermal and mechanical loads (axial loading and loading torque) and can be used to develop new designs of cooled and uncooled blades, discs and rotors of different materials, for experimental determination of resource blades of turbomachines. The invention can be used in the aircraft engine industry, energy and other industries.

Known installation for testing blades of turbomachines for thermostast described in NASA Tech. Brief, No. 12, 1990, R. This installation includes serially connected high-frequency generator and a multiturn inductor, air supply system, the external cooling device, an input connected to the output of the system supply air measurement system, temperature sensor, the output of which is connected to the input of the measurement system, the unit of the lower clamp, United with the root part of the blade, the device records video.

The disadvantage of this setup is the inability to test blades of turbomachines, subjected to axial loading and the loading torque of the PTO is the same. Furthermore, the design of the inductor provides heating of the blades close to uniform. The use of this inductor to play a given non-uniform heating is impractical.

The closest to the technical nature of the claimed invention is an installation for testing blades of turbomachines fatigue (troschenko V.T., Voloschenko A.P. and other Automated system studies of the bearing capacity of working blades of GTE in terms of software power and thermal loading. Scientific principles and methods to improve the reliability and durability of the CCD. Kiev: Naukova Dumka, 1979, p.140-149). The described system includes a serially connected high frequency generator and the inductor, the control device heating, the output of which is connected to the input of the high-frequency generator, the air supply system, the external cooling device, an input connected to the output of the system supply air measurement system, block the contact temperature sensors, the output of which is connected to the input of the measurement system, the device vipranarayana, the device of the lower clamp, United with the root part of the blade.

The disadvantages of this device is the inability to test blades of turbomachines of axial loading and the loading torque and low accuracy test is, one of the following reasons:

1) no device internal cooling, which does not allow for the test conditions of the cooled turbine blades,

2) high frequency generator operating at reduced frequency electric current (66 kHz), which reduces the fidelity thermostress condition of the blades.

Authors ' invention solves the problem of creating the possibility of testing blades of turbomachines of axial loading and the loading torque and increase the accuracy of testing blades due to more accurate reproduction of operational modes. This is achieved as follows:

1) install device axial loading and loading torque

2) installing your internal cooling

3) increase the frequency of electric current of high frequency induction heating,

4) improving the effectiveness of external cooling by providing a flow of air between the blade surface and the inner surface of the inductor, thereby reducing the time of testing.

The problem is solved in that the installation for testing blades of turbomachines on thermomechanical fatigue, containing serially connected high frequency generator and the inductor, the control device for the heating, the output of which is EN with the input of the high-frequency generator, the air supply system, the external cooling device, an input connected to the output of the system supply air measurement system, block the contact temperature sensors, the output of which is connected to the input of the measurement system, the unit of the lower clamp, United with the root part of the blade is provided with axial loading, upper clamp, connected to the bottom end portion of the blade, the control device axial loading, the first dynamometer connected to the upper clamp, device load torque with the second dynamometer control unit for loading the torque input device information, power frame, non-contact temperature sensor, generator non-standard signals and oil pump system, internal cooling, and the outputs of the probe block and non-contact temperature sensor, the first and second dynamometers and generator of non-standard signals are connected to inputs of the input device, the outputs of the input device are connected to inputs of the control devices heating, axial loading, the loading of the torque measurement system and the external cooling device, the output device external cooling supplied to the inductor, the input device internal OHL the input voltage is connected to the output of the system air supply.

The axial loading device includes a hydraulic cylinder with a piston rod, electroservices, the input and outputs of which are connected respectively with the output of the control device of the axial nagruzheniem and inputs cylinder.

The device of the lower clamp includes serially connected bottom grip, which is connected with the shank of the blade, the hinge, the second lower grip connected to the first piston of the first cylinder.

The output of the internal cooling is connected with the cavity of the lower grip.

The arrangement of the upper clamp includes serially connected first upper grip, coupled with a shelf of an end section of the blade, a spherical head with profiled inserts, dynamometer with two blocks of load cells, thrust bearing, upper grip, coupled with a load-bearing frame, the output of one unit of load cells connected to the input of the input device, the output of another block of load cell connected to the input of the measurement system.

Device load torque includes serially connected hydraulic cylinder with a piston rod dynamometer with two blocks of load cells and the lever is hinge connected to the first upper grip, electroservices, the input and outputs of which are connected respectively with the output of the control device of the loading torque m the ment and the inputs of the cylinder, the output of one of the blocks of load cells connected to the input of the input device, the output of another block of load cell connected to the input of the measurement system.

Devices of the upper and lower clamps and the body of hydraulic cylinders mounted on the power rack, which is connected to the housing of the high-frequency generator.

The drawing schematically shows the setup for testing blades of turbomachines on thermomechanical fatigue.

Installation for testing blades of turbomachines on thermomechanical fatigue contains serially connected high-frequency generator 1 and the inductor 2, the device 3 to control the heating system 4 air supply, block 5-contact temperature sensors, the device 6 of the lower clamp, United with the root part of the blade, the device 7 of the axial loading device 8 of the upper clamp, United with shelf end portion of the blade, the device 9 controls the axial loading, the first dynamometer 10 blocks 11 and 12 of the load cells connected to the device 8 of the upper clamp device 13 of the loading torque, the second dynamometer 14 blocks 15 and 16 of the load cells the device 17 controls the loading of the torque device 18 input power frame 19, the proximity sensor 20 temperature, the generator 21 non-standard signals, a measurement system 22, the oil pump is a system of 23, the housing (not shown) of the high-frequency generator 1, the device 24 external cooling device 25 internal cooling, input devices 24 and 25 are connected to the outputs of the system 4 air supply, the output device 24 external cooling supplied to the inductor 2. The device 7 axial loading contains the first hydraulic cylinder 26 with the first rod 27 of the piston, the first schrotenboer 28, the input and outputs of which are connected respectively with the output device 9 controls the axial loading and the inputs of the first hydraulic cylinder 26. The device 6 of the lower clamp includes serially connected bottom grip 29 connected to the shank of the blade, the hinge 30, the second lower grip 31 connected with the first piston rod 29 of the piston of the first hydraulic cylinder 26. The output device 25 internal cooling is connected with the cavity of the lower gripper 29. The device 8 of the upper clamp includes serially connected first upper grip 32 connected to the bottom end section of the blade, a spherical head 33 with profiled inserts, the dynamometer 10, the thrust bearing 34, the second upper grip 35 is connected to the load-bearing frame 19. The device 13 loading torque contains connected in series with the second hydraulic cylinder 36 with the second rod 37 of the piston, the second dynamometer 14 and the lever 38 with a hinge connected to the first upper grip 32, the second alekh serviceman 39, the input and outputs of which are connected respectively with the output device 17 controls the loading of the torque and the input of the second hydraulic cylinder 36. Moreover, the output unit 5 contact sensor and proximity sensor 20 temperature, the first 10 and second 14 dynamometers and generator 21 non-standard signals are connected to the input device 18 of the input information, the output unit 18 of the information input is connected to the input device 3 to control the heating, 7 axial loading and 13 of the loading torque, the output device 9 controls the axial loading is connected to the device 7 axial loading, the output device 17 controls the loading torque is connected to the device 13 of the loading torque. Device top 9 and the bottom 7 of the clamp body of the first 28 and second 36 hydrocylinders mounted on the power rack 16, which is connected to the housing of the high-frequency generator 1. Installation for testing blades of turbomachines on thermomechanical fatigue works in the following way. In the device 18 input information is entered, the program cyclic tests of blades, each test cycle consists of three stages. Device top 9 and the bottom 7 of the clamp body of the first 28 and second cylinders 36 are installed on the power frame 16, which is connected to the housing of the high-frequency generator 1 Outputs eleclrosurgical 28 and 39 connected respectively to the inputs of the cylinders 26 and 36, and their inputs respectively to the outputs of the control unit 9 of the axial loading device 17 torque control and oil pump system 23. The device 7 axial loading contains the first hydraulic cylinder 26 with the first rod 27 of the piston, the first electroservices 28. On the surface of the blades of the turbomachine set the probe block. The first rod 29 of the piston of the first hydraulic cylinder device 26 7 axial loading combined with the second lower grip 31, which is connected to the hinge 30. The hinge 30 connects with the lower gripper 29, in which is inserted the shank of the blade.

The device 6 of the lower clamp includes serially connected bottom grip 31, the hinge 30, the second lower grip 31. On the dynamometer 10 set the blocks 11 and 12 load cells, on the dynamometer 14 blocks 15 and 16 of the load cells. The second upper grip 35 is connected with a load-bearing frame 19. The thrust bearing 34 is connected with the second upper grip 35. The dynamometer 10 is connected with a thrust bearing 34 and with a spherical head 33 with the core liners. The first upper grip 32 is connected with a spherical head 33. The end part of the blade set at the top of the grip 32. The device 8 of the upper clamp includes serially connected first upper grip 32, a spherical head 33 with profiled inserts, the dynamometer 10, the thrust bearing 34, vtoro the upper grip 35. The dynamometer 14 connects with the rod 37 of the piston of the second geroldinger 36 and lever 38. The lever 38 with a hinge connected to the first upper grip 32. The device 13 loading torque contains connected in series with the second hydraulic cylinder 36 with the second rod 37 of the piston, the second dynamometer 14 and the lever 38 with a hinge connected to the first upper grip 32.

Install two core plate (not shown) with holes inductor 2 near the blade surface. Plate inductor 2 cover the blade from both sides. The inductor 2 is connected with a high-frequency generator 1.

To the inductor 2 sum output device 24 external cooling. The output device 25 internal cooling is combined with the cavity of the lower gripper 29, which is connected to the internal cooling channel of the blade. The system outputs 4 air supply is connected to the inputs of the devices 24 and 25.

Near the hole of the plate inductor 2 installing the proximity sensor 20 temperature.

The outputs of blocks 12 and 16 gauges, block 5 thermocouples connected to the inputs of the measurement system 22. The outputs of blocks 11 and 15 and the generator 21 non-standard signals and proximity sensor 20 is connected with the input device 18 of the input device.

High-frequency generator 1, the device 18 input system 23 measurements and devices 9, 17, 3 control and on the other system connected to a power source (not shown).

The device 24 internal cooling device 25 external cooling device regulation and flow measurement of air (not shown). Dynamometers 10 and 14 have water ogladanie (not shown).

From system 4 serving the air in the device 25 internal cooling. Next, the cooling air through the cavity of the lower gripper 29 is fed into the internal channel cooling vanes. Using the inductor heat the blade and make debugging a given temperature distribution on the blade. Includes oil pump system 23. (Before testing device 7 axial loading and the device 13 loading torque with blocks 11 and 14 of the strain gages, the system 22 measurements with blocks 12 and 16 strain gauges, generator, custom signals, block 5 sensors, non-contact temperature sensor system 22 measurement device regulation and flow measurement taruruuto special exemplary means).

Cyclic tests are carried out according to a given program. Each test cycle is performed in three stages over a specified time. During the three stages of the internal cooling air is continuously fed from the device 25 through the cavity of the lower grip 29 in the inner channel of the scapula.

From the high-frequency generator 1 electric current fed into the coil 2. Using inductor the blade is heated to a predetermined minimum temperature. Devices 6, 7, 8, and 13 set the specified minimum value of the axial load and the load torque.

In the first phase of the test cycle, the signals from the device 18 input information fed to the device 3, 9, 17 to increase the temperature, axial loads and loads of torque. The actual temperature from the unit 5, the axial load from the block 11 of the strain gages and load torque from block 15 of the strain gages are served in the device 18 and compared with the maximum specified values. Thus, in the first stage, increase the input power of the heat from the coil, the temperature of the blades from the specified minimum to the maximum values to provide a specified temperature distribution on the blade, axial load and the load torque from the specified minimum to the specified maximum values. Upon reaching temperature, the axial load and the load from the torque specified maximum values of the first phase ends and the device 18 outputs signals of the devices 3, 9 and 17 to maintain these values. As a result, the first stage temperature, axial load and the load torque of the blades increase rate corresponding to a given program.

In the second phase of the test cycle is reduced by the water heating power to the inductor 2, withstand a certain time constant temperatures, axial loads and loads of torque. From block 5, block 11 and block 14, the signals are sent to the input device 18 of the input information. In the case of deviations from the maximum values of temperature, axial load and the load torque of the blades with the output device 18 corrective signals are fed into the device 3, 9 and 17 to maintain a constant temperature, axial loads and loads of torque.

In the third stage of the test cycle, reduce the temperature, axial load and the load torque of the scapula to the specified minimum values. At the beginning of the third stage from the input device 18 serves signal "off" in the device 3 to control the heating of the blades and the signals in the device 9 and 17 to reduce axial loads and loads of torque. As a result, the device 3 and the high-frequency generator 1 is turned off and the electric current is not supplied to the inductor 2. In addition, from the device 18 of the input information signal "enable" is served in the device 24 external cooling. As the output device 24 connected to the inner surface of the inductor 2 external cooling air flows between the blade surface and the inner surface of the inductor 2. The blade is cooled outside the outer in what suham and air, flowing through the internal channel, and the temperature of the blades is reduced. As a result, the third stage of the reduction temperature, axial loads and loads of torque to the minimum value.

Synchronous change of temperature, axial loads and loads of torque on the installation can be carried out also from the proximity sensor 20 temperature or from the generator 21 non-standard signals.

On the stated installation were tested cooled turbine blades of aircraft GTE on thermomechanical fatigue with playback of non-stationary thermal state, axial loading, and the loading torque.

When these tests as a generator was used modernised high frequency generator VCG/0,44, devices, axial loading, and the loading torque - Gidrostroy., servo-valves - automatic device SU-35, the input device is a computer system, measurement system and measurement computer system, block the contact temperature probes - thermocouple, non-contact temperature sensor is a thermal imaging camera or pyrometer.

We offer installation for testing blades of turbomachines mechanical fatigue allows you to test in a short time and to improve their quality due to the full-time playback operating modes.

1. Installation for testing blades of turbomachines on thermomechanical fatigue, containing serially connected high frequency generator and the inductor, the control device heating, the output of which is connected to the input of the high-frequency generator, the air supply system, the external cooling device, an input connected to the output of the system supply air measurement system, block the contact temperature sensors, the output of which is connected to the input of the measurement system, the unit of the lower clamp, United with the root part of the blade, characterized in that the installation is provided with axial loading, upper clamp, connected to the bottom end portion of the blade, the control device axial loading, the first dynamometer connected to the upper clamp, the device of the loading torque, containing a second dynamometer control unit for loading the torque input device information, power frame, non-contact temperature sensor, a generator of non-standard signals, oil pump system and internal cooling, and the outputs of the probe block and non-contact temperature sensors, the first and second dynamometers and generator of non-standard signals are connected to inputs of the device enter the information, the outputs of the input device are connected to inputs of the control devices heating, axial loading, the loading torque measurement system and the external cooling device, the output device external cooling supplied to the inductor, the input of the internal cooling is connected to the output of the system air supply.

2. Installation according to claim 1, characterized in that the device axial immersion contains a hydraulic cylinder with a piston rod, electroservices, the input and outputs of which are connected respectively with the output of the control device of the axial loading and the inputs of the cylinder.

3. Installation according to claim 1, characterized in that the device of the lower clamp includes serially connected bottom grip, which is connected with the shank of the blade, the hinge, the second lower grip connected to the piston rod of the hydraulic cylinder.

4. Apparatus according to claims 1 and 3, characterized in that the output of the internal cooling is connected with the cavity of the lower grip.

5. Installation according to claim 1, characterized in that the arrangement of the upper clamp includes serially connected first upper grip, coupled with a shelf of an end section of the blade, a spherical head with profiled inserts, dynamometer with two blocks of load cells, thrust bearing, upper grip, coupled with a load-bearing frame, the output of one nl the ka strain gages connected to the input of the input device, the output of another block of load cell connected to the input of the measurement system.

6. Installation according to claim 1, characterized in that the device load torque includes serially connected hydraulic cylinder with a piston rod dynamometer with two blocks of load cells and the lever is hinge connected to the first upper grip, electroservices, the input and outputs of which are connected respectively with the output device control nagruzhenii from the torque and the input cylinder, outputs one of the blocks of load cells connected to the input of the input device, the output of another block of load cell connected to the input of the measurement system.

7. Installation according to claim 1, characterized in that the devices of the upper and lower clamps and the body of hydraulic cylinders mounted on the power rack.

8. Installation according to claim 3, characterized in that the power frame is fastened on the housing of the high-frequency generator.



 

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