A creep fatigue tester capable of monitoring the change in the diameter of a round pipe shaft

Abstract

The application discloses a kind of creep fatigue testers capable of monitoring the change of round tube shaft diameter, comprising: sample protection tube, upper sleeve head, lower sleeve head, pressure inlet pipe and locking part;Two ends of sample protection tube are respectively detachably provided with upper cover and lower cover;The bottom end of lower sleeve head is fixed on lower cover, and the top end of lower sleeve head is provided with a first plug-in slot;The bottom end of upper sleeve head is provided with a second plug-in slot, the top end of upper sleeve head is provided with a third plug-in slot, and a first through hole for connecting the second plug-in slot and the third plug-in slot is provided on the upper sleeve head;The bottom end of pressure inlet pipe penetrates through the upper cover and is sealingly inserted and fixed with the third plug-in slot, and the locking part is connected between the pressure inlet pipe and the upper cover;The shaft diameter measuring mechanism is connected between the upper cover and the lower cover, and the detection end of the shaft diameter measuring mechanism can rotate with the axis of the round tube sample tube as the center.The application can monitor the change process of the shaft diameter of the round tube sample tube at every point around the round tube during creep fatigue test.

Description

Technical Field

[0001] This invention relates to the field of circular tube creep fatigue testing equipment, and in particular to a creep fatigue testing instrument capable of monitoring changes in the shaft diameter of a circular tube. Background Technology

[0002] Pipe fittings are widely used in nuclear power plants, chemical plants, and oil and gas transportation, typically operating under high temperature and pressure, an environment that can easily damage pipelines. To test pipeline performance and predict their service life, a high-temperature creep fatigue tester can be used to test scaled-down pipe samples. However, some high-temperature creep fatigue testers use micrometers for direct contact measurement, allowing only timed and point-based measurements of radial changes, and cannot continuously monitor the entire process of diameter changes at every point along the circumference of the pipe. Summary of the Invention

[0003] To address the technical problems existing in the background art, the present invention proposes a creep fatigue testing instrument capable of monitoring changes in the diameter of a circular tube shaft.

[0004] The present invention proposes a creep fatigue testing instrument capable of monitoring changes in the diameter of a circular tube, comprising: a sample protection tube, an upper cover, a lower cover, an upper sleeve, a lower sleeve, a pressure inlet tube, and a locking component;

[0005] The upper cap is detachably placed on the top of the sample protection tube, and the lower cap is detachably placed on the bottom of the sample protection tube.

[0006] The bottom end of the lower sleeve is fixedly connected to the lower cover, and the top end of the lower sleeve is provided with a first insertion groove for sealing and inserting with the round tube sample tube.

[0007] The upper sleeve is positioned above the lower sleeve, and the bottom end of the upper sleeve is provided with a second insertion groove for sealing and inserting with the round tube sample tube. The top end of the upper sleeve is provided with a third insertion groove for sealing and inserting with the pressure inlet tube. The upper sleeve is also provided with a first through hole for connecting the second insertion groove and the third insertion groove. The first through hole is used to connect the pressure inlet tube with the round tube sample tube.

[0008] The bottom end of the pressure inlet pipe passes through the upper cover and is sealed and fixedly inserted into the third insertion groove; the locking element is connected between the pressure inlet pipe and the upper cover, and the locking element is used to fix the pressure inlet pipe and the upper cover relatively or loosen them relatively.

[0009] The shaft diameter measuring mechanism is connected between the upper and lower caps, and the probe end of the shaft diameter measuring mechanism can rotate around the axis of the round tube sample tube. The shaft diameter measuring mechanism is used to monitor the shaft diameter of the round tube sample tube in real time.

[0010] Furthermore, the shaft diameter measuring mechanism includes an upper rotating disk, a lower rotating disk, a rotation drive assembly, and a shaft diameter measuring assembly;

[0011] The upper rotating disk is rotatably mounted on the upper cover, and the lower rotating disk is rotatably mounted on the lower cover, with the lower rotating disk and the upper rotating disk arranged coaxially;

[0012] The upper sleeve is coaxially arranged below the upper rotating disk, and the lower sleeve is coaxially arranged below the upper sleeve, with the bottom end of the lower sleeve passing through the middle of the lower rotating disk and fixedly connected to the lower cover.

[0013] The rotation drive assembly is connected to the upper or lower rotating disk, and the rotation drive assembly is used to drive the upper or lower rotating disk to rotate.

[0014] The shaft diameter measuring component is connected between the upper and lower rotating disks. The shaft diameter measuring component can rotate around the axis of the round tube sample tube as the center. The shaft diameter measuring component is used to monitor the shaft diameter of the round tube sample tube in real time.

[0015] Furthermore, the shaft diameter measuring assembly includes: a support rod, a first spring, a second spring, a force sensor, and a ceramic sleeve;

[0016] The top of the upper rotating disk is provided with a first mounting groove extending radially, and the top of the lower rotating disk is provided with a second mounting groove extending radially at a position corresponding to the first mounting groove.

[0017] The top end of the support rod is slidably connected to the first mounting groove along the extension direction of the first mounting groove, and the bottom end of the support rod is slidably connected to the second mounting groove along the extension direction of the second mounting groove.

[0018] The ceramic sleeve is rotatably mounted on the support rod, and the ceramic sleeve is used to make rolling contact with the round tube sample tube.

[0019] The first spring is connected between the top end of the support rod and the groove wall of the first mounting groove located on the radial inner side, and the second spring is connected between the bottom end of the support rod and the groove wall of the second mounting groove located on the radial inner side.

[0020] The force sensor is connected between the first spring or the second spring and the groove wall of the first mounting groove or the second mounting groove located on the radially inner side.

[0021] Furthermore, the first and second springs have the same specifications.

[0022] Furthermore, it also includes a thermocouple, with a second through hole for the thermocouple to pass through in the lower cover. The probe end of the thermocouple passes through the second through hole and extends into the sample protection tube, while the fixed end of the thermocouple is fixed to the second through hole.

[0023] Furthermore, the lower cover is provided with a protective gas inlet, and the protective gas inlet is detachably sealed.

[0024] Furthermore, water jackets are wrapped around the top and bottom of the sample protection tube.

[0025] Furthermore, a sealing ring is connected between the upper cap and the top of the sample protection tube, and a sealing ring is connected between the lower cap and the bottom of the sample protection tube.

[0026] Furthermore, the locking element is a sealing sleeve. The upper cover has a third through hole for the pressure inlet pipe to pass through. The inner circumferential wall of the third through hole has a second internal thread. The sealing sleeve is fitted and fixed on the pressure inlet pipe. The outer circumferential wall of the bottom end of the sealing sleeve has a second external thread that matches the second internal thread. The sealing sleeve is threadedly connected to the second internal thread through the second external thread to fix the pressure inlet pipe relative to the upper cover.

[0027] Furthermore, the upper cap is fixed to the top of the sample protection tube by an upper quick-release clamp, and the lower cap is fixed to the bottom of the sample protection tube by a lower quick-release clamp.

[0028] This invention presents a creep fatigue testing instrument capable of monitoring changes in the diameter of a circular tube. Gas is introduced through a pressurized inlet pipe, sequentially passing through a third insertion slot, a first through hole, and a second insertion slot into the circular tube sample tube. When the circular tube sample tube expands and deforms due to the internal gas pressure, this expansion force is transmitted to the probe end of the diameter measuring mechanism, causing it to move outwards, thus recording the total tensile force value during this process. When the probe end of the diameter measuring mechanism completes one revolution around the circular tube sample tube, it measures all the deformation around the tube. By accumulating deformation data around each revolution, the process deformation at each point around the tube can be monitored. Therefore, this invention can monitor the diameter at each point around the circular tube sample tube during creep fatigue testing, thereby facilitating the understanding and recording of the diameter change process at each point around the circular tube sample tube. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of a creep fatigue testing instrument capable of monitoring changes in the diameter of a circular tube, according to one embodiment of the present invention.

[0030] Figure 2 for Figure 1 Enlarged view of point A in the image. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] Reference Figure 1 The present invention proposes a creep fatigue testing instrument capable of monitoring changes in the diameter of a circular tube, comprising: a sample protection tube 1, an upper cover 2, a lower cover 3, an upper sleeve 9, a lower sleeve 10, a pressure inlet tube 11, and a locking component 12;

[0033] The upper cover 2 is detachably installed on the top of the sample protection tube 1, and the lower cover 3 is detachably installed on the bottom of the sample protection tube 1.

[0034] The bottom end of the lower sleeve 10 is fixedly connected to the lower cover 3, and the top end of the lower sleeve 10 is provided with a first insertion groove for sealing and inserting with the round tube sample tube 20.

[0035] The upper sleeve 9 is arranged above the lower sleeve 10, and the bottom end of the upper sleeve 9 is provided with a second insertion groove for sealing and inserting with the round tube sample tube 20. The top end of the upper sleeve 9 is provided with a third insertion groove for sealing and inserting with the pressure inlet tube 11. The upper sleeve 9 is provided with a first through hole for connecting the second insertion groove and the third insertion groove. The first through hole is used to connect the pressure inlet tube 11 with the round tube sample tube 20.

[0036] The bottom end of the pressure inlet pipe 11 passes through the upper cover 2 and is sealed and fixedly inserted into the third insertion groove; the locking member 12 is connected between the pressure inlet pipe 11 and the upper cover 2, and the locking member 12 is used to fix the pressure inlet pipe 11 and the upper cover 2 relatively or loosen them relatively.

[0037] The shaft diameter measuring mechanism is connected between the upper cover 2 and the lower cover 3, and the probe end of the shaft diameter measuring mechanism can rotate around the axis of the round tube sample tube 20. The shaft diameter measuring mechanism is used to monitor the shaft diameter of the round tube sample tube 20 in real time.

[0038] In practical use, gas is introduced into the circular tube sample tube 20 through the pressure inlet pipe 11 and then sequentially through the third insertion slot, the first through hole, and the second insertion slot. When the circular tube sample tube 20 expands and deforms due to the internal gas pressure, the expansion force is transmitted to the probe end of the shaft diameter measuring mechanism, causing it to move outward, thereby recording all the tensile force values ​​during the process. When the probe end of the shaft diameter measuring mechanism circles the circular tube sample tube 20, it measures all the deformation of the circular tube around one circumference. By accumulating the deformation data circle by circle, the process deformation at each point around the circular tube can be monitored.

[0039] This invention can monitor the shaft diameter at every point around the circumference of the circular tube sample tube 20 during creep fatigue testing of the circular tube, thereby facilitating the understanding and recording of the shaft diameter change process at every point around the circumference of the circular tube sample tube 20.

[0040] In this embodiment, the shaft diameter measuring mechanism includes an upper rotating disk 4, a lower rotating disk 5, a rotation drive assembly, and a shaft diameter measuring assembly;

[0041] The upper rotating disk 4 is rotatably mounted on the upper cover 2, and the lower rotating disk 5 is rotatably mounted on the lower cover 3, with the lower rotating disk 5 and the upper rotating disk 4 arranged coaxially.

[0042] The upper sleeve 9 is coaxially arranged below the upper rotating disk 4, and the lower sleeve 10 is coaxially arranged below the upper sleeve 9, with the bottom end of the lower sleeve 10 passing through the middle of the lower rotating disk 5 and fixedly connected to the lower cover 3.

[0043] The rotation drive assembly is connected to the upper rotating disk 4 or the lower rotating disk 5, and the rotation drive assembly is used to drive the upper rotating disk 4 or the lower rotating disk 5 to rotate.

[0044] The shaft diameter measuring component is connected between the upper rotating disk 4 and the lower rotating disk 5. The shaft diameter measuring component can rotate around the axis of the round tube sample tube 20. The shaft diameter measuring component is used to monitor the shaft diameter of the round tube sample tube 20 in real time.

[0045] In practical use, the rotation drive assembly drives the upper rotating disk 4 or the lower rotating disk 5 to rotate, causing the probe end of the shaft diameter measuring mechanism to rotate together, and the probe end of the shaft diameter measuring mechanism to revolve around the circular tube sample tube 20.

[0046] When the probe end of the shaft diameter measuring mechanism circles the circular tube sample tube 20 once, it measures all the deformation of the circular tube around one circumference. By accumulating the deformation data circle by circle, the process deformation of the shaft diameter at each point around the circular tube can be monitored.

[0047] Reference Figure 1 and Figure 2 In a further embodiment, the shaft diameter measuring assembly includes: a support rod 6, a first spring 8, a second spring, a force sensor 17, and a ceramic sleeve 7;

[0048] The top of the upper rotating disk 4 is provided with a first mounting groove extending radially, and the top of the lower rotating disk 5 is provided with a second mounting groove extending radially at the position corresponding to the first mounting groove.

[0049] The top end of the support rod 6 is slidably connected to the first mounting groove along the extension direction of the first mounting groove, and the bottom end of the support rod 6 is slidably connected to the second mounting groove along the extension direction of the second mounting groove.

[0050] The ceramic sleeve 7 is rotatably mounted on the support rod 6, and the ceramic sleeve 7 is used to make rolling contact with the round tube sample tube 20.

[0051] The first spring 8 is connected between the top end of the support rod 6 and the groove wall of the first mounting groove located on the radial inner side, and the second spring is connected between the bottom end of the support rod 6 and the groove wall of the second mounting groove located on the radial inner side.

[0052] Force sensor 17 is connected between the first spring 8 or the second spring and the groove wall of the first mounting groove or the second mounting groove located on the radially inner side.

[0053] In practical use, the rotation drive assembly drives the upper rotating disk 4 or the lower rotating disk 5 to rotate, causing the support rod 6 to rotate together with the ceramic sleeve 7. The ceramic sleeve 7 rotates and revolves around the circular tube sample tube 20 at the same time.

[0054] When the circular tube sample tube 20 expands and deforms due to the internal gas pressure, the expansion force is transmitted to the ceramic sleeve 7, causing it to move outward, which in turn causes the first spring 8 or the second spring to deform, and the force sensor 17 records all the tensile force values ​​during this process.

[0055] When the ceramic sleeve 7 wraps around the round tube sample tube 20 once, the deformation of the round tube is measured for one circumference. By accumulating the deformation data round by round, the process deformation of the shaft diameter at each point around the round tube can be monitored.

[0056] Of course, in order to ensure that the forces applied to the upper and lower ends of the support rod 6 are equal, in this embodiment, the first spring 8 and the second spring have the same specifications.

[0057] In one specific embodiment, the ceramic sleeve 7 is rotatably mounted on the support rod 6 via a bearing.

[0058] In another embodiment, the shaft diameter measuring component is a laser measuring component or an ultrasonic ranging component, so as to facilitate the measurement of the process deformation of the shaft diameter at each point around the circumference of the circular tube sample tube 20.

[0059] In this embodiment, a thermocouple 13 is also included. The lower cover 3 has a second through hole for the thermocouple 13 to pass through. The probe end of the thermocouple 13 passes through the second through hole and extends into the sample protection tube 1. The fixed end of the thermocouple 13 is fixed to the second through hole to facilitate temperature measurement.

[0060] In one specific embodiment, the inner peripheral wall of the second through hole is provided with a first internal thread, and the outer peripheral wall of the fixed end of the thermocouple 13 is provided with a first external thread that matches the first internal thread. The first external thread is threadedly connected to the first internal thread to fix the fixed end of the thermocouple 13 to the second through hole.

[0061] In another specific embodiment, the fixed end of the thermocouple 13 is sealed and fixed to the second through hole.

[0062] In a further embodiment, the lower cover 3 is provided with a protective gas inlet, and the protective gas inlet is detachably provided with a sealing member 15 to facilitate the entry of protective gas.

[0063] To prevent the protective gas from escaping, in a further embodiment, a sealing ring is connected between the upper cap 2 and the top end of the sample protection tube 1, and a sealing ring is connected between the lower cap 3 and the bottom end of the sample protection tube 1.

[0064] In this embodiment, water jackets 14 are respectively wrapped around the top and bottom of the sample protection tube 1 to cool both ends of the sample protection tube 1.

[0065] In this embodiment, the rotation drive assembly includes a motor 19 and a gear 18. The outer periphery of the upper rotating disk 4 or the lower rotating disk 5 is provided with multiple gear teeth along the circumferential direction. The gear 18 is rotatably mounted on the upper cover 2 or the lower cover 3, and the gear 18 is meshed with the gear teeth. The output shaft of the motor 19 is coaxially and fixedly connected to the gear 18.

[0066] Specifically, the motor 19 is installed on the upper cover 2 or the lower cover 3 at a position corresponding to the gear 18, so as to drive the gear 18 to rotate.

[0067] In this embodiment, the locking member 12 is a sealing sleeve. The upper cover 2 has a third through hole for the pressure inlet pipe 11 to pass through. The inner circumferential wall of the third through hole is provided with a second internal thread. The sealing sleeve is sleeved and fixed on the pressure inlet pipe 11. The outer circumferential wall of the bottom end of the sealing sleeve is provided with a second external thread that matches the second internal thread. The sealing sleeve is threadedly connected to the second internal thread through the second external thread so that the pressure inlet pipe 11 is relatively fixed to the upper cover 2.

[0068] In one specific embodiment, the upper sleeve 9 is tightly fitted with the round tube sample tube 20 through front and rear retainers, and the lower sleeve 10 is tightly fitted with the round tube sample tube 20 through front and rear retainers to achieve a sealing effect.

[0069] To facilitate the disassembly and installation of the upper cover 2 and the lower cover 3, in one specific embodiment, the upper cover 2 is fixed to the top of the sample protection tube 1 by an upper quick-release clamp 16, and the lower cover 3 is fixed to the bottom of the sample protection tube 1 by a lower quick-release clamp.

[0070] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A creep-fatigue tester capable of monitoring changes in the diameter of a round tube shaft, characterized by, The utility model relates to a kind of test sample protection tube, which comprises: The upper cover (2) is detachably capped on the top end of the test sample protection tube (1), and the lower cover (3) is detachably capped on the bottom end of the test sample protection tube (1). The bottom end of the lower sleeve head (10) is fixedly connected with the lower cover (3), and the top end of the lower sleeve head (10) is provided with a first insertion slot for sealingly inserting the round tube sample tube. The upper sleeve head (9) is arranged above the lower sleeve head (10), and the bottom end of the upper sleeve head (9) is provided with a second insertion slot for sealingly inserting the round tube sample tube. The pressure inlet pipe (11) is fixedly connected with the third insertion slot by penetrating the upper cover (2) at the bottom end, and the locking member (12) is connected between the pressure inlet pipe (11) and the upper cover (2). The shaft diameter measuring mechanism is connected between the upper cover (2) and the lower cover (3). The shaft diameter measuring mechanism comprises an upper rotating disc (4), a lower rotating disc (5), a rotating driving assembly and a shaft diameter measuring assembly. The shaft diameter measuring assembly is connected between the upper rotating disc (4) and the lower rotating disc (5), and can rotate around the axis of the round tube sample tube. The shaft diameter measuring assembly comprises a support rod (6), a first spring (8), a second spring, a force sensor (17) and a ceramic sleeve (7).

2. The creep-fatigue tester capable of monitoring the change in the diameter of a round pipe shaft according to claim 1, characterized by, The top end of the upper rotating disc (4) is provided with a first installation slot extending in the radial direction, and the top of the lower rotating disc (5) is provided with a second installation slot extending in the radial direction at the corresponding position of the first installation slot. The top end of the support rod (6) is slidably connected in the first installation slot in the extension direction of the first installation slot, and the bottom end of the support rod (6) is slidably connected in the second installation slot in the extension direction of the second installation slot. The ceramic sleeve (7) is rotatably sleeved on the support rod (6), and is used for rolling contact with the round tube sample tube. The first spring (8) is connected between the top end of the support rod (6) and the slot wall on the inner side in the radial direction of the first installation slot, and the second spring is connected between the bottom end of the support rod (6) and the slot wall on the inner side in the radial direction of the second installation slot. The upper rotating disc (4) is rotatably installed on the upper cover (2), and the lower rotating disc (5) is rotatably installed on the lower cover (3). The upper sleeve head (9) is coaxially arranged below the upper rotating disc (4), and the lower sleeve head (10) is coaxially arranged below the upper sleeve head (9). The bottom end of the lower sleeve head (10) is fixedly connected with the lower cover (3) by penetrating the middle part of the lower rotating disc (5). The rotating driving assembly is connected with the upper rotary disc (4) or the lower rotary disc (5), and is used for driving the upper rotary disc (4) or the lower rotary disc (5) to rotate.

3. The creep-fatigue tester capable of monitoring the change in the diameter of a round tube shaft according to claim 1, characterized by, The first spring (8) and the second spring are of the same specification.

4. The apparatus for monitoring the change in the diameter of a round tube according to any one of claims 1 to 3, characterized in that, The thermocouple (13) is further included, the lower cover (3) is provided with a second through hole for the thermocouple (13) to pass through, a detection end of the thermocouple (13) extends into the sample protection tube (1) through the second through hole, and a fixed end of the thermocouple (13) is fixed with the second through hole.

5. The creep-fatigue tester capable of monitoring the change in the diameter of a round tube shaft according to claim 4, characterized by, The lower cover (3) is provided with a protective gas inlet, and the protective gas inlet is detachably provided with a plugging piece (15).

6. The creep-fatigue tester capable of monitoring the change in the diameter of a round tube shaft according to claim 5, characterized by, Sealing rings are connected between the upper cover (2) and the top end of the sample protection tube (1) and between the lower cover (3) and the bottom end of the sample protection tube (1).

7. The creep-fatigue tester capable of monitoring the change in the diameter of a round tube shaft according to claim 4, characterized by, The top end and the bottom end of the sample protection tube (1) are respectively surrounded by water jackets (14).

8. The creep-fatigue tester capable of monitoring the change in the diameter of a round tube shaft according to claim 1, characterized by, The locking piece (12) is a sealing pressing sleeve, the upper cover (2) is provided with a third through hole for the pressure inlet pipe (11) to pass through, an inner peripheral wall of the third through hole is provided with a second internal thread, the sealing pressing sleeve is sleeved and fixed on the pressure inlet pipe (11), an outer peripheral wall of a bottom end of the sealing pressing sleeve is provided with a second external thread matched with the second internal thread, and the sealing pressing sleeve is screw-connected with the second internal thread through the second external thread, so that the pressure inlet pipe (11) is relatively fixed with the upper cover (2).

9. The creep-fatigue tester capable of monitoring the change in the diameter of a round tube shaft according to claim 1, characterized by, The upper cover (2) is fixed on the top end of the sample protection tube (1) through an upper quick-release clamp (16), and the lower cover (3) is fixed on the bottom end of the sample protection tube (1) through a lower quick-release clamp.

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