CN116637733A - Temperature calibration test method for in-situ heating of centrifugal machine under high rotation speed and high temperature - Google Patents

Abstract

The invention discloses a temperature calibration test method for in-situ heating of a centrifugal machine under the action of high rotation speed and high temperature. Parameters of a centrifugal machine and a test sample are determined, a temperature correction sample and a plurality of test samples are installed in a sample chuck, and a thermocouple is inserted; keeping static under the condition that the centrifugal machine is not started, controlling the induction heating system and the circulating water cooling system to work by the vacuumizing temperature control system, applying temperature load to the test sample and the temperature correction sample, and preserving heat after the temperature reaches a preset temperature; analyzing and processing to obtain parameters of the upper and lower induction coils during formal test measurement; and (3) withdrawing the temperature correction sample, replacing the test sample, starting the spindle of the centrifugal machine to rotate and reach the rotating speed, and controlling according to the parameters obtained in the fifth step until the test sample is broken and broken. The invention solves the defect that the radiation heating at high rotating speed can only check the ambient temperature but can not check the temperature of the sample accurately, and can check the temperature of the sample directly at high rotating speed, so that the temperature of the test part is more accurate.

Description

A temperature calibration test method for in-situ heating of centrifuges under the action of high speed and high temperature

technical field

The invention relates to a centrifuge heating and temperature calibration control method in the field of in-situ heating of metal materials, in particular to a temperature calibration test method for in-situ heating of a centrifuge for metal materials under the action of high rotation speed and high temperature.

Background technique

National standard GB/T 38822-2020 "Creep-fatigue test method for metal materials" and GB/T6825.1-2008 "Inspection of static uniaxial testing machine Part 1: Tensile and (or) compression testing machine force measurement system "Inspection and Calibration" all stipulate the test methods for the mechanical properties of metal materials, but the test environment specified in these standards is 1G (G=9.8m/s ² ), which can satisfy the research on the mechanical properties of metal materials themselves. However, in turbo propulsion systems, such as aeroengines, aerospace engines, gas turbines for industry and ships, turbochargers for automobiles and trains, and other key components of power systems, such as compressor blades, fan blades, turbine working blades, etc. They are always in a state of high-speed rotation, that is, the service environment is usually a centrifugal hypergravity environment.

The turbine propulsion system is usually a turbine power device that converts the heat energy of fuel combustion into mechanical energy through the guide vanes on the working blades through thermal expansion to drive the turbine to convert heat energy into mechanical energy. The thermal expansion works to convert the waste heat of the engine into mechanical energy. When in service, the turbine working blades of these power plants rotate around the engine axis at high speed, and their function is to expand the gas to do work, converting the potential energy and thermal energy of the gas into the mechanical work of the rotor, so the loads on the turbine working blades during service include aerodynamic force, Centrifugal forces and thermal loads. Among them, the centrifugal force generated by high-speed rotation belongs to body force, which mainly causes radial tensile stress on the blade, and torsional stress on the blade with torsion structure at the same time. If the stacking line of the blade does not completely coincide with the radial line, the centrifugal force will also cause the blade to generate bending stress. The thermal stress generated by thermal load is closely related to the temperature gradient and geometric constraints of the blade. The greater the temperature gradient of the blade, the greater the thermal stress. However, the key material mechanical performance data currently used to design the turbine blades of the turbine propulsion system come from the durability, creep, fatigue and other testing machines under 1G conditions to obtain the mechanical performance data of the material under static and uniaxial stress states by testing standard specimens. Although the mechanical performance data of the standard sample can provide a design basis for the strength design of the turbine blade of the turbine propulsion system to a certain extent, due to the complex geometry of the blade, its complex stress state is different from that of the standard sample. The mechanical performance data of materials cannot be directly used to evaluate the life of turbine blades without considering the influence of high speed, blade geometry, etc. on its structural reliability.

Contents of the invention

In view of the shortcomings of the current static mechanical performance test of metal materials under 1G, and the lack of in-situ heating and temperature calibration methods suitable for the test process of the mechanical properties of metal materials under the action of high speed and high temperature, the present invention provides a method that can be used in a high-speed rotation environment. The method of in-situ heating and temperature calibration is applied to metal materials to solve the key problems of in-situ heating, temperature calibration and intelligent temperature control in the process of testing the mechanical properties of metal materials under the action of high speed and high temperature.

The in-situ heating of metal materials in a high-rotational environment in the present invention means that during the mechanical performance testing process of metal materials or components, the test materials or components rotating at high speed are always in a state of in-situ heating until the end of the test.

The temperature check of the metal material in-situ heating system under the high-speed environment of the present invention refers to the in-situ temperature distribution of the test material or component in the high-speed rotating state or static state during the test process of the mechanical properties of the metal material or component. Temperature measurement and calibration.

The high temperature mentioned in the present invention means that the heating temperature applied to the designated area of the sample during the experiment is not lower than 500°C, and the duration of in-situ heating is not lower than the test time.

The high rotational speed in the present invention means that the maximum rotational speed of the centrifuge during the experiment is not less than 5000 rpm.

The technical scheme adopted in the present invention:

Step 1: Determine the spindle speed and disc radius of the centrifuge according to the experimental conditions;

The second step: determine the size and weight of the mass block in the test sample, the size and geometric center of the gauge length section;

Step 3: Determine the test temperature and the centrifugal stress applied by the geometric center of the gauge section, and then determine the rotational speed corresponding to the centrifugal stress of the geometric center of the gauge section, and determine the distance between the geometric center of the gauge section and the center of the main shaft of the centrifuge;

Step 4: Install a temperature calibration sample in one slot of the sample chuck and the test sample in the remaining slots, and install the temperature calibration sample next to the test sample; in each thermocouple hole of the temperature calibration sample Thermocouples are inserted in the middle, and the temperature control thermocouples are fixed at the geometric center of the gauge length section of the test sample and the temperature calibration sample;

Step 5: Without starting the centrifuge, keep the sample chuck and the test sample and temperature calibration sample on it still, vacuumize the environment, and then start the induction heating system, circulating water cooling system and temperature control System, through the temperature control system to control the induction heating system and the circulating water cooling system to apply temperature load to the test sample and the temperature calibration sample, and keep it warm for a period of time after the temperature reaches the predetermined temperature;

The temperature data obtained by the temperature control thermocouples of the test sample and the temperature calibration sample and the thermocouples in each thermocouple hole of the temperature calibration sample are analyzed and processed to obtain the upper induction coil and the lower induction coil during the formal test measurement. Parameters of energizing current, current alternating frequency and distance between the upper induction coil and the lower induction coil;

Step 6: Remove the temperature calibration sample from the slot of the sample chuck, replace it with the test sample, and then start the centrifuge, so that the main shaft of the centrifuge rotates and the speed reaches the speed corresponding to the centrifugal stress to conduct a formal test. The parameters obtained in the five steps control the distance between the upper induction coil and the lower induction coil, the energizing current, and the alternating frequency of the current, and keep the parameters unchanged until the test sample is broken.

The method uses a temperature calibration test device, which includes a sample chuck, an induction heating system, a circulating water cooling system, and a temperature control system; the sample chuck is coaxially installed on the main shaft of the centrifuge and rotates synchronously with the main shaft of the centrifuge. The test sample and the temperature calibration sample are installed on the sample chuck, the induction heating system is installed coaxially on the centrifuge and does not rotate with the main shaft of the centrifuge, the induction heating system is connected with the circulating water cooling system, and the temperature control system is connected with the circulating water cooling system respectively. Water cooling system, test specimen connection.

The sample chuck includes a disc body, a card slot and a flange. Flanges are coaxially installed at both ends of the center of the disc body. The disc body is fixedly connected with the main shaft of the centrifuge through the flange. A plurality of draw-in slots are provided, and the plurality of draw-in slots are arranged at intervals along the circumferential direction, and each draw-in slot is used for installing a test sample.

The test sample is in the shape of a strip, including successively connected mass blocks, standard moment sections, load-bearing sections and assembly tenons, and the mass blocks, standard moment sections, load-bearing sections and assembly tenons are all sequentially Arrangement, the assembly tenon is embedded in the slot of the sample chuck.

The temperature calibration sample and the test sample have the same structure, shape and size, the difference is that a plurality of thermocouple holes with different depths are opened inside the temperature calibration sample, and each thermocouple hole is along the sample card. The disk body of the disk is arranged radially, and each thermocouple hole is equipped with a thermocouple.

The induction heating system includes an upper induction coil, an upper fixed plate, a lower induction coil and a lower fixed plate; the upper fixed plate and the lower fixed plate are fixedly arranged in parallel at intervals up and down, and in the interval between the upper fixed plate and the lower fixed plate The sample chuck is arranged; the ring-shaped upper induction coil and the lower induction coil are respectively fixed on the bottom surface of the upper fixing plate, the lower fixing plate and the top surface through the upper induction coil insulation layer and the lower induction coil insulation layer.

The upper induction coil and the lower induction coil are respectively wrapped in the inner chambers of the upper induction coil insulation layer and the lower induction coil insulation layer, and the inner chambers of the upper induction coil insulation layer and the lower induction coil insulation layer are connected through pipes, and the upper induction coil The insulating layer and the insulating layer of the lower induction coil are respectively fixed on the bottom surface of the upper fixing plate, the lower fixing plate and the top surface through the upper fixing screw rod and the lower fixing screw rod.

The circulating water cooling system includes a pipe assembly set in the induction heating system, a water inlet pipe, a water outlet pipe, a positive electrode, an inner insulating sleeve, a metal sleeve, a negative electrode, a copper pipe, an insulating pressure sleeve, and a fixing flange , insulating pressure sleeve, compression round nut, seal, electrode insulation pressure sleeve, external water outlet pipe, external positive electrode plate, external water inlet pipe and external negative electrode plate; the copper tube jacket is equipped with insulation pressure for insulation from the metal casing The outer cover of the insulating pressure sleeve is equipped with a metal sleeve; the middle part of the metal sleeve is sealed in the center hole of the fixed flange through the insulating pressure sleeve and the shaft seal ring, and the fixed flange is fixed on the experimental chamber cover of the centrifuge. The two ends of the pipe, insulating sleeve and metal sleeve are respectively fixed and sealed through the inner insulating sleeve and the seal; one end of the copper pipe passes through the inner insulating sleeve and is coaxially connected with the flow outlet pipe, and one end of the copper pipe passes through the inner insulation The end behind the sleeve is provided with a positive electrode; the external positive electrode plate is electrically connected to the copper tube through the electrode insulation pressure sleeve, so that the positive electrode is directly electrically connected to the external positive electrode plate through the copper tube; the other end of the copper tube is connected to the external water outlet pipe. Make the circulation outlet pipe flow directly through the copper pipe and the external outlet pipe; there is an annular pipe gap between the insulating pressure sleeve and the metal sleeve as the water inlet channel, and one end of the water inlet channel is connected through the metal pipe and the circulation inlet pipe. The water pipe is provided with a negative electrode near the end; the external negative electrode plate is electrically connected to the metal sleeve through the compression round nut, so that the negative electrode is electrically connected to the external negative electrode plate after passing through the metal pipe and the metal sleeve; the metal sleeve is connected The pipe wall at one end of the sealing element is provided with a through groove, and the through groove is fluidly connected with the external water inlet pipe, so that the circulation water inlet pipe flows through the metal pipe, the water inlet channel, the through groove and the external water inlet pipe in turn.

The pipeline assembly includes a heating water inlet pipe, a water inlet pipe sealing sleeve, a heating water outlet pipe and a water outlet pipe sealing sleeve; The outlet pipe is connected, and the other ends of the heating water inlet pipe and the heating outlet pipe are respectively connected to the inner cavity environment where the upper induction coil and the lower induction coil are located in the induction heating system, and the inner cavity environment where the upper induction coil and the lower induction coil are located are connected to each other .

The external water outlet pipe and the external water inlet pipe are respectively connected to the water inlet and water outlet of the circulating water machine.

The positive electrode and the negative electrode are electrically connected to the upper induction coil and the lower induction coil respectively, and the external positive electrode plate and the external negative electrode plate are respectively connected to the positive and negative electrodes of the external power supply.

The temperature control system includes a thermocouple, a thermocouple extension wire, a high-speed slip ring, a data acquisition module, a data conversion transmission module and a high-frequency AC power supply cabinet; the upper induction coil and the lower induction coil of the induction heating system are positive The corresponding test samples are fixed with thermocouples on the surface, and the thermocouples are connected to the data acquisition module through the thermocouple extension line, the high-speed slip ring, and the data acquisition module is connected to the high-frequency AC power supply cabinet through the data conversion and transmission module. The AC power supply cabinet is electrically connected to the external positive electrode plate and the external negative electrode plate of the circulating water cooling system.

Since the heating system is heated by induction outside the test piece, the temperature of the outer surface of the test piece will be higher than the internal temperature, resulting in a yield effect. The effectiveness of component testing and testing is greatly reduced, and the test error is increased.

In order to avoid such problems, the present invention has just designed a temperature calibration device and a temperature calibration process. By means of the temperature calibration device and the temperature calibration process, the test sample in the formal test can have a uniform temperature distribution when heated, and the temperature everywhere reaches the predetermined temperature. Set the temperature with an error not greater than five degrees Celsius.

The temperature calibration of the present invention can ensure that the temperature of the test piece along the vertical direction of centrifugal force is uniform without gradient, and the temperature along the direction of centrifugal force can be uneven and have gradient.

The beneficial effects of the present invention are:

(1) It solves the problem that the current radiation heating can only check the ambient temperature but cannot accurately check the temperature of the sample at high rotational speeds. The temperature calibration test method provided by the invention can directly check the temperature of the sample at high rotational speeds, so that The temperature of the test part is more accurate;

(2) By changing the shape of the check sample and installing the spacing and depth of the thermocouples, the temperature at any position of the sample can be checked as needed.

Description of drawings

Fig. 1 is the structural representation of sample chuck 1;

Fig. 2 is the structural representation of test sample 1.1;

Fig. 3 is the structural representation of induction heating system 2;

Fig. 4 is the structural representation of circulating water cooling system 3;

Fig. 5 is the schematic diagram of temperature control system 4;

Fig. 6 is a structural representation of a test sample 1.1;

Fig. 7 is a schematic structural view of a test sample 1.1;

Fig. 8 is a schematic structural view of a test sample 1.1;

Fig. 9 is a schematic diagram of the installation of the sample chuck 1 and the induction heating system 2 on the centrifuge;

Fig. 10 is a process route diagram of specific implementation one of heating;

Fig. 11 is the process roadmap of specific implementation two of heating;

Fig. 12 is the process roadmap of specific implementation three of heating;

Fig. 13 is the structural representation of temperature calibration sample 5;

Fig. 14 is a layout diagram after the test sample 1.1, the temperature calibration sample 5, the sample chuck 1 and the induction heating system 2 are installed together.

In the picture:

Sample chuck 1: test sample 1.1, slot 1.2, flange 1.3;

Mass block 1.1.1, standard moment section 1.1.2, bearing section 1.1.3, assembly tenon 1.1.4;

Induction heating system 2: upper induction coil 2.1, upper induction coil insulating layer 2.2, upper fixing plate 2.3, upper fixing screw 2.4, lower induction coil 2.5, lower induction coil insulating layer 2.6, lower fixing plate 2.7, lower fixing screw 2.8, connection Rod 2.9, nut 2.10, heating water inlet pipe 2.11, water inlet pipe sealing sleeve 2.12, heating water outlet pipe 2.13, water outlet pipe sealing sleeve 2.14;

Circulating water cooling system 3: circulating water inlet pipe 3.1, connecting nut 3.2, circulating water outlet pipe 3.3, connecting nut 3.4, positive electrode 3.5, inner insulating sleeve 3.6, negative electrode 3.8, copper pipe 3.9, insulating pressure sleeve 3.10, fixed flange 3.11 , fixed screw rod 3.12, shaft sealing ring 3.13, insulating gland 3.14, compression round nut 3.15, top tightening nut 3.16, insulator 3.17, seal 3.18, electrode insulation gland 3.19, sealing nut 3.20, external outlet pipe 3.21, External positive electrode plate 3.22, external water inlet pipe 3.23 and external negative electrode plate 3.24;

Temperature control system 4: thermocouple 4.1, thermocouple extension wire 4.2, high-speed slip ring 4.3, data acquisition module 4.4, control software 4.5, data conversion and transmission module 4.6, high-frequency AC power supply cabinet 4.7;

Calibration sample 5: thermocouple hole 5-1, thermocouple hole 5-2, thermocouple hole 5-3, thermocouple hole 5-4, thermocouple hole 5-5, thermocouple hole 5-6, thermocouple Holes 5-7.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific implementation.

As shown in Figure 9, a temperature calibration test device is designed in the specific implementation, and the device includes a sample chuck 1, an induction heating system 2, a circulating water cooling system 3 and a temperature control system 4; the sample chuck 1 is coaxially installed on the centrifuge The main shaft rotates synchronously with the main shaft of the centrifuge. The test sample 1.1 and the temperature calibration sample 5 are installed on the sample chuck 1. The induction heating system 2 is coaxially installed on the centrifuge and does not keep fixed with the main shaft rotation of the centrifuge. The heating system 2 is connected to the circulating water cooling system 3, and the temperature control system 4 is respectively connected to the circulating water cooling system 3 and the test sample 1.1.

The centrifuge is an ultra-gravity centrifuge.

As shown in Figure 1, the function of the sample chuck 1 is to install the test sample and connect with the centrifuge through the main shaft, including the disc body, the slot 1.2 and the flange 1.3, and the two ends of the disc center are coaxially fixed with Flange 1.3, the disc body is coaxially fixedly connected with the main shaft of the centrifuge through flange 1.3, a plurality of card slots 1.2 are arranged around the disc body along the circumferential direction, and the plurality of card slots 1.2 are arranged at intervals along the circumferential direction, each card slot 1.2 For mounting a test specimen 1.1.

The flange 1.3 is used to connect the sample chuck 1 with the main shaft of the centrifuge. During the experiment, the high-speed rotation of the main shaft of the centrifuge drives the sample chuck 1 to rotate, thereby applying a centrifugal load to the test sample 1.1.

The slot 1.2 is mainly used to fix the test sample 1.1 rotating at high speed, and the assembly tenon 1.1.4 of the test sample 1.1 is installed in the slot 1.2, so that the sample chuck 1 drives the test sample 1.1 to rotate together when rotating.

3. According to claim 1, a method for calibrating the temperature of a centrifuge heated in situ under the action of high rotating speed and high temperature, characterized in that:

As shown in Figure 2, the test sample 1.1 is processed by the metal material for testing performance, and is in the shape of a strip, including the sequentially connected mass block 1.1.1, standard moment section 1.1.2, load-bearing section 1.1.3 and assembly Tenon 1.1.4, quality block 1.1.1, standard moment section 1.1.2, load-bearing section 1.1.3 and assembly tenon 1.1.4 are arranged sequentially along the strip of test sample 1.1, specifically mass block 1.1.1, The standard moment section 1.1.2, the load-bearing section 1.1.3 and the assembly tenon 1.1.4 are arranged radially outward from the slot 1.2 of the sample chuck 1, and the assembly tenon 1.1.4 is embedded in the clamp of the sample chuck 1 slot 1.2.

In the specific implementation, the width of the assembly tenon 1.1.4 and the groove width of the sample chuck 1 are larger than the width of the mass block 1.1.1, the standard moment section 1.1.2 and the load-bearing section 1.1.3, so that the test sample 1.1 When driven by the sample chuck 1 to rotate at high speed, it can be stably embedded and positioned.

The mass block 1.1.1 is used to apply a centrifugal stress to the standard moment section 1.1.3 by the centrifugal force generated by its own weight at high rotational speed. The mass of the mass block 1.1.1 is m, the effective radius is r, and the rotational speed is ω, then the centrifugal force F=mrω ² generated by the mass block 1.1.1 is fast. The mass m of the mass 1.1.1 depends on the breaking strength of the material under the experimental conditions.

The gauge length section 1.1.2 is connected with the mass block 1.1.1, and is used to carry the centrifugal stress and thermal stress load imposed by the mass block 1.1.1 under high-speed rotation and high temperature. The shape of gauge length section 1.1.2 can be changed according to actual needs.

The load-bearing section 1.1.3 is used to connect the gauge length section 1.1.2 and the assembly tenon 1.1.4.

According to the needs of the experiment, the test sample 1.1 can be designed with the structure shown in Figure 2, Figure 6-Figure 8.

As shown in Figure 13, the temperature calibration sample 5 and the test sample 1.1 have the same structure, shape, and size. The difference is that there are multiple thermocouple holes with different depths inside the temperature calibration sample 5, and each thermocouple hole is Arranged along the radial direction of the disc body of the sample chuck 1, each thermocouple hole is equipped with a thermocouple.

In specific implementation, the temperature calibration sample 5 is provided with thermocouple holes 5-1, thermocouple holes 5-2, thermocouple holes 5-3, thermoelectric Couple holes 5-4, thermocouple holes 5-5, thermocouple holes 5-6, thermocouple holes 5-7, each thermocouple hole is equipped with a thermocouple, and the thermocouple is packed into the bottom of the thermocouple hole.

In order to check the temperature of sections A, B, C, D, E, F, and G on the temperature calibration sample 5, a thermocouple hole 5-1, a thermocouple hole 5-2, and a thermocouple hole 5-1 are punched on the temperature calibration sample 5. Hole 5-3, thermocouple hole 5-4, thermocouple hole 5-5, thermocouple hole 5-6, and thermocouple hole 5-7 correspond to sections A, B, C, D, E, F, and G, respectively. When checking, insert the thermocouple into thermocouple hole 5-1, thermocouple hole 5-2, thermocouple hole 5-3, thermocouple hole 5-4, thermocouple hole 5-5, thermocouple hole 5-6 , thermocouple holes 5-7, and then connect the thermocouples to the temperature control system 4. In specific experiments, the number and depth of thermocouple holes can be adjusted.

One or both of thermocouples and strain gauges are arranged in the center of the gauge length section 1.1.2 of the test sample 1.1 and the temperature calibration sample 5.

As shown in Figure 3, the function of the induction heating system 2 is to heat the high-speed rotating sample in situ, and to apply temperature load to the designated area of the test sample 1.1. It includes an upper induction coil 2.1, an upper fixed plate 2.3, a lower induction coil 2.5 and a lower fixed plate 2.7; the upper fixed plate 2.3 and the lower fixed plate 2.7 are respectively fixed and arranged at intervals up and down in parallel, and in specific implementation, the main shaft of the centrifuge can rotate through 2.3 Arrangement over the fixed plate. The sample chuck 1 is arranged in the interval between the upper fixed plate 2.3 and the lower fixed plate 2.7; the upper fixed plate 2.3 and the lower fixed plate 2.7 are supported and fixed by the connecting rod 2.9, and the outer end of the connecting rod 2.9 is provided with a nut 2.10 for installation. The annular upper induction coil 2.1 and the lower induction coil 2.5 are respectively fixed on the bottom surface of the upper fixing plate 2.3 and the lower fixing plate 2.7 and the top surface through the upper induction coil insulation layer 2.2 and the lower induction coil insulation layer 2.6.

The upper fixing plate 2.3 and the lower fixing plate 2.7 are ring-shaped plates, and the upper induction coil 2.1 and the lower induction coil 2.5 are overall ring-shaped coils.

Specifically, the upper induction coil 2.1 and the lower induction coil 2.5 are respectively wrapped in the inner cavity of the upper induction coil insulating layer 2.2 and the lower induction coil insulating layer 2.6, and the inner cavity of the upper induction coil insulating layer 2.2 and the lower induction coil insulating layer 2.6 The upper induction coil insulating layer 2.2 and the lower induction coil insulating layer 2.6 are respectively fixed on the bottom surface of the upper fixing plate 2.3 and the lower fixing plate 2.7 and the top surface through the upper fixing screw 2.4 and the lower fixing screw 2.8.

Among them, the upper induction coil 2.1 is wrapped inside the upper induction coil insulation layer 2.2 to prevent conduction and is used for insulation; then the upper induction coil 2.1 with the insulation layer is fixed on the upper fixing plate 2.3 by the upper fixing screw 2.4 to form the upper induction coil The lower induction coil 2.5 is wrapped inside the lower induction coil insulating layer 2.6, and the lower induction coil 2.5 with the insulating layer is also fixed on the lower fixing plate 2.7 by the lower fixing screw 2.8 to form the lower induction coil; subsequently, the upper fixing plate 2.3 and the lower fixing The plates 2.7 are assembled together by connecting rods 2.9 and nuts 2.10.

In the case of alternating current, the metal material placed between the upper induction coil 2.1 and the lower induction coil 2.5 generates an induced current I or an eddy current under the action of an alternating magnetic field, and the eddy current generates heat through a resistive conductor, which is heated by heat conduction For metal materials, the Joule heat Q=I ² RtR generated by the induced current I is the resistance of the metal material, and t is time. During the induction heating process, by adjusting the frequency f of the alternating current and the sample distance between the upper induction coil 2.1 and the lower induction coil 2.5 The distance between them and the heating power are used to control the heating temperature.

As shown in FIG. 4 , the function of the circulating water cooling system 3 is to cool the copper tubes in the upper induction coil 2.1 and the lower induction coil 2.5 in the induction heating system 2 . Including the pipeline assembly set in the induction heating system 2, the circulation inlet pipe 3.1, the circulation outlet pipe 3.3, the positive electrode 3.5, the inner insulating sleeve 3.6, the metal sleeve 3.7, the negative electrode 3.8, the copper pipe 3.9, the insulating pressure sleeve 3.10, the fixing Flange 3.11, insulating gland 3.14, compression round nut 3.15, seal 3.18, electrode insulating gland 3.19, external water outlet pipe 3.21, external positive electrode plate 3.22, external water inlet pipe 3.23 and external negative electrode plate 3.24;

The outer radial direction of the copper tube 3.9 is set coaxially with an insulating sleeve 3.10 and a metal sleeve 3.7, and the outer fixed coaxial sleeve of the copper tube 3.9 is equipped with an insulating sleeve 3.10 and an insulating sleeve 3.10 for insulation from the metal sleeve 3.7 The outer coaxial sleeve is equipped with a metal sleeve 3.7, so that the insulation between the copper tube 3.9 and the metal sleeve 3.7 is maintained; the middle part of the metal sleeve 3.7 is sealed and fitted in the center hole of the fixed flange 3.11 through the insulating pressure sleeve 3.14 and the shaft sealing ring 3.13 Among them, the fixed flange 3.11 is fixed on the experimental chamber cover of the centrifuge through the fixed screw rod 3.12, and the two ends of the copper tube 3.9, the insulating sleeve 3.10 and the metal sleeve 3.7 are respectively fixed and sealed through the inner insulating sleeve 3.6 and the seal 3.18, Insulate and prevent water leakage through the inner insulating sleeve 3.6 and the seal 3.18;

One end of the copper pipe 3.9 passes through the inner insulating sleeve 3.6 and is coaxially connected with the circulation outlet pipe 3.3, and a positive electrode 3.5 is set at the end of the copper pipe 3.9 after passing through the inner insulating sleeve 3.6; the external positive electrode plate 3.22 passes through multiple electrodes The insulating gland 3.19 is electrically connected to the copper pipe 3.9. Specifically, at least two electrode insulating glands 3.19 are threaded onto the external threads of the copper pipe 3.9, wherein two adjacent electrode insulating glands 3.19 are compressed and installed with The externally connected positive electrode plate 3.22, the externally connected positive electrode plate 3.22 passes through the gap between two adjacent electrode insulating sleeves 3.19 and maintains electrical connection with the externally connected positive electrode plate 3.22. In this way, the positive electrode 3.5 is directly electrically connected to the external positive electrode plate 3.22 through the copper tube 3.9;

The other end of the copper pipe 3.9 is connected to the external outlet pipe 3.21 through the sealing nut 3.20, so that the circulation outlet pipe 3.3 is directly circulated through the copper pipe 3.9 and the external outlet pipe 3.21;

There is an annular pipe gap between the insulating gland 3.10 and the metal sleeve 3.7 for the water inlet channel, and the water inlet channel is connected to the metal pipe and the circulation water inlet pipe 3.1 at the end close to the inner insulation sleeve 3.6, and the circulation water inlet pipe 3.1 is at the end The negative electrode 3.8 is set near the center; the external negative electrode plate 3.24 is electrically connected to the metal sleeve 3.7 through a plurality of compression round nuts 3.15, specifically, at least two compression round nuts 3.15 are threaded on the external thread of the metal sleeve 3.7 , wherein an external negative electrode plate 3.24 is compressed and installed between two adjacent compression round nuts 3.15, and the external negative electrode plate 3.24 passes through the gap between two adjacent compression round nuts 3.15 and the external negative electrode plate 3.24 Stay electrically connected. In this way, the negative electrode 3.8 is electrically connected to the external negative electrode plate 3.24 after sequentially passing through the metal pipe and the metal sleeve 3.7;

The metal casing 3.7 is provided with a through groove on the pipe wall at one end of the connecting seal 3.18, between the external positive electrode plate 3.22 and the external negative electrode plate 3.24, and the through groove is connected to the external water inlet pipe 3.23. Specifically, around the through groove The metal casing 3.7 is set with the insulator 3.17 through the top tightening nut 3.16, and the external water inlet pipe 3.23 passes through the through hole and the through groove on the insulator 3.17 to communicate; in this way, the circulation inlet pipe 3.1 passes through the metal pipe, the water inlet channel, and the through channel in turn. After the tank, it communicates with the external water inlet pipe 3.23;

More specifically, the copper tube 3.9 is a long hollow copper tube, and an insulating compression sleeve 3.10 is installed on the periphery for insulation, and a sealing ring is installed to prevent air leakage from the experimental cavity.

The circulation inlet pipe 3.1 is connected to the heating water inlet pipe 2.11 of the induction heating system 2 through the connection nut 3.2; the circulation outlet pipe 3.3 is connected to the heating outlet pipe 2.13 of the induction heating system 2 through the connection nut 3.4; the positive electrode 3.5 is installed on the periphery of the circulation outlet pipe 3.3 , to ensure that the cooling water can be cooled to the positive electrode 3.5; the negative electrode 3.8 is installed on the periphery of the circulation inlet pipe 3.1, to ensure that the cooling water can be cooled to the negative electrode 3.8.

The metal casing 3.7 is installed on the chamber cover of the experimental chamber with 6 fixed screw rods 3.12 through the flange 3.11, and then the shaft seal ring 3.13 is used to prevent air leakage, and the insulation pressure sleeve 3.14 is used to insulate to prevent leakage; on the insulation pressure sleeve 3.14 , the external negative electrode plate 3.24 is fixedly installed through three compression round nuts 3.15; the external water inlet pipe 3.23 is connected with the through groove of the copper pipe 3.9 through the tightening nut 3.16 and the insulator 3.17, and the replacement or maintenance is facilitated by the tightening nut 3.16 The external water inlet pipe 3.23 and the insulator 3.17 prevent electric leakage of the motor; on the seal 3.18, the external positive electrode plate 3.22 is fixed through the electrode insulating pressure sleeve 3.19; on the electrode insulating pressure sleeve 3.19, the external water outlet pipe 3.21 is connected to the circulation The copper pipe Unicom of outlet pipe 3.3.

The pipeline assembly includes a heating water inlet pipe 2.11, a water inlet pipe sealing sleeve 2.12, a heating outlet pipe 2.13 and an outlet pipe sealing sleeve 2.14; The circulation inlet pipe 3.1 and the circulation outlet pipe 3.3 are connected, and the other ends of the heating water inlet pipe 2.11 and the heating outlet pipe 2.13 are respectively connected to the inner cavity environment where the upper induction coil 2.1 and the lower induction coil 2.5 in the induction heating system 2 are located. The inner chamber environment where the coil 2.1 and the lower induction coil 2.5 are located communicate with each other.

Specifically, the other end of the heating water inlet pipe 2.11 is respectively connected through the water inlet pipe sealing sleeve 2.12, the connecting nut 3.2 and the circulation water inlet pipe 3.1, and the other end of the heating water outlet pipe 2.13 is respectively connected through the water outlet pipe sealing sleeve 2.14, the connection nut 3.4 and the circulation outlet pipe 3.3 Connections.

The external water outlet pipe 3.21 and the external water inlet pipe 3.23 are respectively connected to the water inlet and the water outlet of the circulating water machine. In specific implementation, the external outlet pipe 3.21 is connected to the water inlet pipe of the circulating water machine, and the external water inlet pipe 3.23 is connected to the outlet pipe of the circulating water machine to form a closed circulating water cooling system to cool down the induction heating system 2 .

The positive electrode 3.5 and the negative electrode 3.8 are electrically connected to the upper induction coil 2.1 and the lower induction coil 2.5 respectively, and the external positive electrode plate 3.22 and the external negative electrode plate 3.24 are respectively connected to the positive and negative poles of the external power supply. In specific implementation, the externally connected positive electrode plate 3.22 is connected to the positive pole of the high-frequency AC power supply cabinet 4.7 as an AC power supply, and the externally connected negative electrode plate 3.24 is connected to the negative pole of the high-frequency AC power supply cabinet 4.7 as an AC power supply to form a closed-loop circuit. The induction heating system 2 provides power.

The inner chamber where the upper induction coil 2.1 is located is connected to the heating water inlet pipe 2.11, and the heating water inlet pipe 2.11 is connected to the circulating water inlet pipe 3.1 of the circulating water cooling system 3 through the water inlet pipe sealing sleeve 2.12; the inner chamber where the lower induction coil 2.5 is located is connected to the heating water outlet pipe 2.13 connection, the heating outlet pipe 2.13 is connected with the outlet pipe sealing sleeve 2.14 and the circulating water outlet pipe 3.3 of the circulating water cooling system 3, and the cooling water provided by the cooling system 3 cools down the copper pipe.

As shown in FIG. 5 , the function of the temperature control system 4 is to ensure that the test sample 1.1 is heated to a predetermined temperature by controlling the heating power of the induction power supply and maintain this temperature until the end of the experiment. Including thermocouple 4.1, thermocouple extension wire 4.2, high-speed slip ring 4.3, data acquisition module 4.4, data conversion and transmission module 4.6 and high-frequency AC power supply cabinet 4.7; the upper induction coil 2.1 and the lower induction coil 2.5 of the induction heating system 2 are positive The surface of the corresponding test sample 1.1 is fixed with a thermocouple 4.1, and the thermocouple 4.1 is connected with the thermocouple extension line 4.2, the high-speed slip ring 4.3 and the data acquisition module 4.4, and the thermocouple extension line 4.2 passes through the sample chuck 1. The disc body and the main shaft of the centrifuge are electrically connected to the high-speed slip ring 4.3, and the high-speed slip ring 4.3 is arranged on the main shaft of the centrifuge. The data acquisition module 4.4 is connected to the high-frequency AC power supply cabinet 4.7 through the data conversion and transmission module 4.6. The AC power cabinet 4.7 is electrically connected to the external positive electrode plate 3.22 and the external negative electrode plate 3.24 of the circulating water machine and the circulating water cooling system 3 .

In the specific implementation, control software 4.5 is also set, and the control software 4.5 is respectively connected with the data acquisition module 4.4 and the data conversion transmission module 4.6.

During the experiment, the thermocouple 4.1 was welded to the center of the upper induction coil 2.1 and the lower induction coil 2.5 corresponding to the test sample 1.1, and then the thermocouple 4.1 was connected to the high-speed slip ring 4.3 through the hollow spindle of the centrifuge through the thermocouple extension line 4.2, and then passed The wire is connected with the data acquisition module 4.4, the control software 4.5, and the data conversion transmission module 4.6, and finally the control signal line is connected with the high-frequency AC power supply cabinet 4.7 to form a temperature control system.

The present invention also designs different samples to better test the mechanical properties of the metal material of the test piece.

The structure of the first test sample 1.1, see Figure 2, is a groove sample and related similar structures;

The structure of the second test sample 1.1, see Figure 6, is a flat plate sample and related similar structures;

The structure of the third test sample 1.1, as shown in Figure 7, is a round bar sample and related similar structures;

The structure of the fourth test sample 1.1, see Fig. 8, the structural gradient sample and its related similar structures.

The temperature calibration device can also provide a variety of in-situ heating modes for high-speed environments, providing new experimental conditions for material performance tests at different temperatures and different speeds. Wherein, the heating mode of the present invention includes but not limited to the following situations:

Heating mode 1: Implement uniform temperature heating mode on the standard moment section 1.1.2 of the test sample 1.1 at high speed, as shown in Figure 10.

The type of experimental material is the same, the distance h between the standard moment section 1.1.2 and the upper induction coil 2.1 and the lower induction coil 2.5 remains the same during the experiment, and the heating power and heating frequency remain unchanged within t time, the standard moment section 1.1 .2 Apply a constant and uniform temperature field.

Heating mode 2: Under the high rotation speed, the alternating temperature heating mode is implemented to periodically change the standard moment section 1.1.2 of the test sample 1.1, as shown in Fig. 11 .

The experimental material type is the same, the distance h between the standard moment section 1.1.2 and the upper induction coil 2.1 and the lower induction coil 2.5 remains the same during the experiment, the heating frequency is constant, but the heating power is periodically changed within the time t, and the standard Section 1.1.2 is an alternating temperature field in which T1 is applied during t1 and T2 is applied within t2.

Heating mode three: a heating mode in which a constant temperature gradient is applied to the standard moment section 1.1.2 of the test sample 1.1 at a high rotational speed, as shown in FIG. 12 .

The experimental material type is the same, the standard moment section 1.1.2 of the test sample 1.1 is processed into a circular arc with a radius of R, and the distance between the lowest end of the standard moment section 1.1.2 arc and the upper induction coil 2.1 and the lower induction coil 2.5 during the experiment The distance h remains the same, and the heating power and heating frequency remain unchanged for t time. Since the distance from the arc-shaped standard moment section 1.1.2 to the induction coil 2.1 and the lower induction coil 2.5 changes continuously, according to the principle of induction heating, under the same power and frequency conditions, the heating temperature of the sample is inversely proportional to the distance from the induction coil to the induction coil. This implements a constant temperature gradient for the standard moment section 1.1.2 of the test specimen 1.1.

The concrete implementation process of the present invention is as follows:

Determine the experimental temperature and centrifuge speed according to the experimental conditions.

Take Figure 10 as an example below to illustrate the high-throughput testing of mechanical properties of materials under the action of high speed and high temperature:

Step 1: Determine the spindle speed and disc radius of the centrifuge according to the experimental conditions;

The second step: determine the size and weight of the mass block 1.1.1 in the test sample 1.1, the size and the geometric center of the gauge length section 1.1.2;

Step 3: Determine the test temperature and the centrifugal stress imposed by the geometric center of the gauge length section 1.1.2, and then determine the rotational speed corresponding to the centrifugal stress at the geometric center of the gauge length section 1.1.2 through finite element calculations, and determine the gauge length section 1.1.2 The distance between the geometric center and the center of the main shaft of the centrifuge;

Step 4: Install a temperature calibration sample 5 in one slot 1.2 of the sample chuck 1 and test sample 1.1 in the remaining slots 1.2 according to the distance of the third step, and install a temperature calibration test sample next to the test sample 1.1. Sample 5; thermocouples are inserted in each thermocouple hole of the temperature calibration sample 5, and the respective temperature control tubes are fixed at the geometric center positions of the gauge length section 1.1.2 of the test sample 1.1 and the temperature calibration sample 5. Thermocouple 4.1, temperature control thermocouple 4.1 is connected with temperature control system 4 through temperature extension wire 4.2;

Calibration sample 5 and test test sample 1.1 are in the same environment, it is considered that the temperature distribution obtained in the calibration sample 5 is the same as that of the test test sample 1.1.

Step 5: Without starting the centrifuge, keep the sample chuck 1 and the test sample 1.1 on it and the temperature calibration sample 5 still, vacuumize the environment inside the centrifuge, and then start the induction heating system 2 , the circulating water cooling system 3 and the temperature control system 4, through the temperature control system 4 to control the induction heating system 2, the circulating water cooling system 3 work to apply a temperature load to the test sample 1.1 and the temperature calibration sample 5, after the temperature reaches the predetermined temperature And keep warm for 30 minutes;

By testing the temperature control thermocouple 4.1 of the test sample 1.1 and the temperature calibration sample 5 and the thermocouple measurement in each thermocouple hole of the temperature calibration sample 5, the temperature data obtained by the temperature change with time is analyzed and processed to obtain the formal test measurement. Parameters of the energizing current, current alternating frequency and power of the upper induction coil 2.1 and the lower induction coil 2.5, and the distance between the upper induction coil 2.1 and the lower induction coil 2.5;

Step 6: Remove the temperature calibration sample 5 from the slot 1.2 of the sample chuck 1 and replace it with the test sample 1.1, so that the test sample 1.1 is installed in each slot 1.2 of the sample chuck 1, and then start the centrifugation machine, make the main shaft of the centrifuge rotate and the rotational speed reaches the rotational speed corresponding to the centrifugal stress to conduct a formal test, and control the distance between the upper induction coil 2.1 and the lower induction coil 2.5 according to the parameters obtained in the fifth step, and the energized current and current alternating frequency and power, keep the parameters constant until the test specimen 1.1 is pulled off and broken.

During the process from when the main shaft of the centrifuge starts to rotate to when the test sample 1.1 is broken, the data of temperature change and stress change are collected in real time through the temperature control thermocouple 4.1 and the strain gauge, and the data of the test sample is measured.

In this way, the temperature of each point is detected by the temperature calibration device, and the parameters are set through the temperature calibration process to adjust the conditions applied in the subsequent test, so that the temperature gradient of the specimen during the test is smaller.

Claims (10)

1. A temperature calibration test method for in-situ heating of a centrifugal machine under the action of high rotation speed and high temperature is characterized by comprising the following steps of:

the first step: determining the spindle rotating speed and the wheel disc radius of the centrifugal machine according to experimental conditions;

and a second step of: determining the size and weight of the mass (1.1.1) in the test specimen (1.1), the size and geometric center of the gauge length section (1.1.2);

and a third step of: determining a test temperature and centrifugal stress applied by the geometric center of the gauge length section (1.1.2), further determining a rotating speed corresponding to the centrifugal stress of the geometric center of the gauge length section (1.1.2), and determining a distance between the geometric center of the gauge length section (1.1.2) and the center of a main shaft of the centrifugal machine;

fourth step: a temperature correction sample (5) is arranged in one clamping groove (1.2) of the sample chuck (1), a test sample (1.1) is arranged in the rest clamping grooves (1.2), and the temperature correction sample (5) is arranged beside the test sample (1.1); thermocouples are inserted into the thermocouple holes of the temperature correction sample (5), and a temperature control thermocouple (4.1) is fixed at the geometric center positions of the gauge length sections (1.1.2) of the test sample (1.1) and the temperature correction sample (5);

Fifth step: under the condition that the centrifugal machine is not started, the sample chuck (1) and the test sample (1.1) and the temperature correction sample (5) on the sample chuck are kept static, the environment is vacuumized, then the induction heating system (2), the circulating water cooling system (3) and the temperature control system (4) are started, the temperature control system (4) is used for controlling the induction heating system (2) and the circulating water cooling system (3) to work, temperature loads are applied to the test sample (1.1) and the temperature correction sample (5), and after the temperature reaches a preset temperature, the temperature is kept for a period of time;

analyzing temperature data obtained by thermocouple measurement in each thermocouple hole of the test sample (1.1) and the temperature correction sample (5) to obtain parameters of energizing current and current alternating frequency of the upper induction coil (2.1) and the lower induction coil (2.5) and the distance between the upper induction coil (2.1) and the lower induction coil (2.5) when in formal test measurement;

sixth step: withdrawing the temperature correction sample (5) from the clamping groove (1.2) of the sample chuck (1), replacing the test sample (1.1), starting the centrifugal machine, enabling the spindle of the centrifugal machine to rotate and enabling the rotating speed to reach the rotating speed corresponding to the centrifugal stress, performing formal test, controlling the interval between the upper induction coil (2.1) and the lower induction coil (2.5) and the alternating frequency of the electrified current and the current according to the parameters obtained in the fifth step, and keeping the parameters unchanged until the test sample (1.1) is broken by being pulled.

2. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 1, wherein the method comprises the following steps: the method adopts a temperature calibration testing device, and the device comprises a sample chuck (1), an induction heating system (2), a circulating water cooling system (3) and a temperature control system (4); the sample chuck (1) is coaxially arranged on a main shaft of the centrifugal machine and synchronously rotates along with the main shaft of the centrifugal machine, the sample chuck (1) is provided with a test sample (1.1) and a temperature correction sample (5), the induction heating system (2) is coaxially arranged on the centrifugal machine and does not rotate along with the main shaft of the centrifugal machine, the induction heating system (2) is connected with the circulating water cooling system (3), and the temperature control system (4) is respectively connected with the circulating water cooling system (3) and the test sample (1.1).

3. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 2, wherein the method comprises the following steps: the sample chuck (1) comprises a disc body, clamping grooves (1.2) and flanges (1.3), the flanges (1.3) are coaxially arranged at two ends of the center of the disc body, the disc body is fixedly connected with a main shaft of a centrifugal machine through the flanges (1.3), a plurality of clamping grooves (1.2) are formed in the periphery of the disc body along the circumferential direction, the clamping grooves (1.2) are arranged at intervals along the circumferential direction, and each clamping groove (1.2) is used for installing one test sample (1.1).

4. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 1, wherein the method comprises the following steps: the test sample (1.1) is in a strip shape, and comprises a mass block (1.1.1), a standard moment section (1.1.2), a bearing section (1.1.3) and an assembling tenon (1.1.4) which are sequentially connected, wherein the mass block (1.1.1), the standard moment section (1.1.2), the bearing section (1.1.3) and the assembling tenon (1.1.4) are sequentially arranged along the strip shape of the test sample (1.1), and the assembling tenon (1.1.4) is embedded in a clamping groove (1.2) of the sample chuck (1).

5. A method for calibrating in-situ heating of a centrifuge under high rotational speed-high temperature action according to claim 3, wherein: the temperature correction sample (5) and the test sample (1.1) have the same structure, shape and size, except that a plurality of thermocouple holes with different depths are formed in the temperature correction sample (5), each thermocouple hole is formed and arranged along the radial direction of the disk body of the sample chuck (1), and each thermocouple Kong Junan is provided with one thermocouple.

6. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 2, wherein the method comprises the following steps: the induction heating system (2) comprises an upper induction coil (2.1), an upper fixing plate (2.3), a lower induction coil (2.5) and a lower fixing plate (2.7); the upper fixing plate (2.3) and the lower fixing plate (2.7) are respectively and fixedly arranged in parallel at an upper-lower interval, and the sample chuck (1) is arranged in the interval between the upper fixing plate (2.3) and the lower fixing plate (2.7); the annular upper induction coil (2.1) and the annular lower induction coil (2.5) are respectively fixed on the bottom surface of the upper fixing plate (2.3) and the bottom surface of the lower fixing plate (2.7) and the top surface through the upper induction coil insulating layer (2.2) and the lower induction coil insulating layer (2.6).

7. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 6, wherein the method comprises the following steps: the upper induction coil (2.1) and the lower induction coil (2.5) are respectively wrapped in the inner cavities of the upper induction coil insulating layer (2.2) and the lower induction coil insulating layer (2.6), the inner cavities of the upper induction coil insulating layer (2.2) and the lower induction coil insulating layer (2.6) are communicated through a pipeline, and the upper induction coil insulating layer (2.2) and the lower induction coil insulating layer (2.6) are respectively fixed on the bottom surface of the upper fixing plate (2.3) and the bottom surface of the lower fixing plate (2.7) and the top surface through an upper fixing screw (2.4) and a lower fixing screw (2.8).

8. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 2, wherein the method comprises the following steps: the circulating water cooling system (3) comprises a pipeline assembly arranged in the induction heating system (2), a circulating water inlet pipe (3.1), a circulating water outlet pipe (3.3), a positive electrode (3.5), an inner insulating sleeve (3.6), a metal sleeve (3.7), a negative electrode (3.8), a copper pipe (3.9), an insulating pressing sleeve (3.10), a fixing flange (3.11), an insulating pressing sleeve (3.14), a pressing round nut (3.15), a sealing element (3.18), an electrode insulating pressing sleeve (3.19), an external water outlet pipe (3.21), an external positive electrode plate (3.22), an external water inlet pipe (3.23) and an external negative electrode plate (3.24); an insulating pressing sleeve (3.10) used for insulating the copper pipe (3.9) from the metal sleeve (3.7) is sleeved outside the copper pipe (3.9), and the metal sleeve (3.7) is sleeved outside the insulating pressing sleeve (3.10); the middle part of the metal sleeve (3.7) is sealed and sleeved in a central hole of the fixed flange (3.11) through the insulating pressing sleeve (3.14) and the sealing ring (3.13) for the shaft, the fixed flange (3.11) is fixed on an experimental cavity cover of the centrifugal machine, and two ends of the copper pipe (3.9), the insulating pressing sleeve (3.10) and the metal sleeve (3.7) are respectively fixed and sealed and installed through the inner insulating sleeve (3.6) and the sealing piece (3.18); one end of the copper pipe (3.9) passes through the inner insulating sleeve (3.6) and then is coaxially butted with the circulating water outlet pipe (3.3), and a positive electrode (3.5) is arranged at the end part of one end of the copper pipe (3.9) which passes through the inner insulating sleeve (3.6); the external positive electrode plate (3.22) is electrically connected with the copper pipe (3.9) through the electrode insulation pressing sleeve (3.19), so that the positive electrode (3.5) is electrically connected with the external positive electrode plate (3.22) after directly passing through the copper pipe (3.9); the other end of the copper pipe (3.9) is in butt joint with the external water outlet pipe (3.21), so that the circulating water outlet pipe (3.3) directly circulates through the copper pipe (3.9) and the external water outlet pipe (3.21); an annular pipeline gap is formed between the insulating pressure sleeve (3.10) and the metal sleeve (3.7) and is used as a water inlet channel, one end of the water inlet channel is communicated and connected with a circulating water inlet pipe (3.1) through a metal pipeline, and a negative electrode (3.8) is arranged near the end part of the circulating water inlet pipe (3.1); the external negative electrode plate (3.24) is electrically connected with the metal sleeve (3.7) through the compression round nut (3.15), so that the negative electrode (3.8) is electrically connected with the external negative electrode plate (3.24) after passing through the metal pipeline and the metal sleeve (3.7) in sequence; the metal sleeve (3.7) is provided with a through groove on the pipe wall at one end of the connecting sealing piece (3.18), and the through groove is in flow connection with the external water inlet pipe (3.23), so that the flow water inlet pipe (3.1) sequentially passes through the metal pipeline, the water inlet channel and the through groove and then flows with the external water inlet pipe (3.23);

The pipeline assembly comprises a heating water inlet pipe (2.11), a water inlet pipe sealing sleeve (2.12), a heating water outlet pipe (2.13) and a water outlet pipe sealing sleeve (2.14); one end of a heating water inlet pipe (2.11) and one end of a heating water outlet pipe (2.13) are respectively connected with a circulating water inlet pipe (3.1) and a circulating water outlet pipe (3.3) through a water inlet pipe sealing sleeve (2.12), a water outlet pipe sealing sleeve (2.14), and the other ends of the heating water inlet pipe (2.11) and the heating water outlet pipe (2.13) are respectively communicated with an inner cavity environment where an upper induction coil (2.1) and a lower induction coil (2.5) in an induction heating system (2) are located, and the inner cavity environments where the upper induction coil (2.1) and the lower induction coil (2.5) are located are mutually communicated.

9. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 8, wherein the method comprises the following steps: the positive electrode (3.5) and the negative electrode (3.8) are respectively and electrically connected to the upper induction coil (2.1) and the lower induction coil (2.5), and the external positive electrode plate (3.22) and the external negative electrode plate (3.24) are respectively connected to the positive electrode and the negative electrode of an external power supply.

10. The method for calibrating the in-situ heating of the centrifugal machine under the action of high rotating speed and high temperature according to claim 2, wherein the method comprises the following steps: the temperature control system (4) comprises a thermocouple (4.1), a thermocouple extension line (4.2), a high-speed sliding ring (4.3), a data acquisition module (4.4), a data conversion transmission module (4.6) and a high-frequency alternating current power supply cabinet (4.7); the induction heating system is characterized in that thermocouples (4.1) are fixedly arranged on the surface of a test sample (1.1) positively corresponding to an upper induction coil (2.1) and a lower induction coil (2.5) of the induction heating system (2), the thermocouples (4.1) are connected with a data acquisition module (4.4) through thermocouple extension lines (4.2), high-speed sliding rings (4.3) and data acquisition modules (4.4), the data acquisition module (4.4) is in communication connection with a high-frequency alternating current power cabinet (4.7) through a data conversion transmission module (4.6), and the high-frequency alternating current power cabinet (4.7) is electrically connected with an external positive electrode plate (3.22) and an external negative electrode plate (3.24) of the circulating water cooling system (3).