CN217766170U - Thermal state strain measurement experiment table for pressure pipeline pipe fitting - Google Patents
Thermal state strain measurement experiment table for pressure pipeline pipe fitting Download PDFInfo
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- CN217766170U CN217766170U CN202221221698.6U CN202221221698U CN217766170U CN 217766170 U CN217766170 U CN 217766170U CN 202221221698 U CN202221221698 U CN 202221221698U CN 217766170 U CN217766170 U CN 217766170U
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Abstract
The utility model discloses a pressure pipeline pipe fitting thermal state strain measurement experiment table, which comprises a pipe fitting to be measured and an experiment table base, and further comprises a first pipe hoop, a second pipe hoop, a hydraulic system, a push disc, a heating device and a plurality of high temperature strain gauges; the first pipe hoop and the second pipe hoop are oppositely arranged on two sides of the table top of the experiment table base, the first pipe hoop is fixedly arranged on the table top of the experiment table base, and the second pipe hoop can slide on the table top of the experiment table base; two ends of the pipe fitting to be tested are respectively fixed on the first pipe hoop and the second pipe hoop; the hydraulic system and the push disc are arranged on the table top of the experiment table base and located on the outer side of the second pipe hoop, the hydraulic system is connected with the push disc, and the hydraulic system can enable the push disc to do linear motion along the axis of the push disc and extrude the end part of the pipe fitting to be tested; the heating device is arranged on the pipe wall to be heated of the pipe fitting to be heated and used for heating the pipe fitting to be heated. The utility model is used for verify and feedback correction finite element calculated result.
Description
Technical Field
The utility model belongs to the technical field of special equipment inspection detects, specifically a pipeline under pressure pipe fitting thermal state strain measurement laboratory bench.
Background
In pressure pipeline inspection, such as pipeline inspection in a boiler range, the phenomenon of crack formation caused by local stress concentration of pipeline pipe fittings due to factors such as blocked expansion of the pipeline, incapability of supporting and hanging frames and the like is common. Because the pipeline is long and complicated in the boiler scope, and the pipeline is inspected comprehensively with great difficulty and long time, so the inspection is usually local spot check, and the position where cracks may exist is found by depending on experience, so that the risk of missing inspection exists. At present, finite element analysis is applied to the examination of pipelines in the boiler range, and a stress cloud chart of a pipeline pipe fitting is calculated by fluid-solid coupling simulation, so that a stress concentration point can be visually seen theoretically. However, the finite element calculation needs to verify the accuracy according to the calculation result of the preset model and the boundary condition, so that a pressure pipeline pipe fitting thermal state strain measurement experiment table is designed to verify and feed back and correct the finite element calculation result.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that a pipeline under pressure pipe fitting thermal state strain measurement laboratory bench is provided for verify and feedback correction finite element calculated result.
In order to solve the technical problem, the utility model adopts the following technical scheme:
a pressure pipeline pipe fitting thermal state strain measurement experiment table comprises a pipe fitting to be measured and an experiment table base, and further comprises a first pipe hoop, a second pipe hoop, a hydraulic system, a push disc, a heating device and a plurality of high temperature strain gauges; the first pipe hoop and the second pipe hoop are oppositely arranged on two sides of the table top of the experiment table base, the first pipe hoop is fixedly arranged on the table top of the experiment table base, and the second pipe hoop can slide on the table top of the experiment table base; two ends of the pipe fitting to be tested are respectively fixed on the first pipe hoop and the second pipe hoop; the hydraulic system and the push disc are arranged on the table top of the experiment table base and located on the outer side of the second pipe hoop, the hydraulic system is connected with the push disc, and the hydraulic system can enable the push disc to do linear motion along the axis of the push disc and extrude the end part of the pipe fitting to be measured; the heating device is arranged on the pipe wall to be heated of the pipe fitting to be heated and is used for heating the pipe fitting to be heated; and the high-temperature strain gauges are externally connected with a strain measuring instrument and used for measuring the strain value of the point to be measured.
Further, the heating device comprises a ceramic heating belt and a temperature control thermocouple; the ceramic heating belt is wound on the pipe wall to be heated of the pipe fitting to be heated, and is externally connected with heat treatment control equipment and used for heating the ceramic heating belt; the temperature control thermocouple is arranged at the edge of the ceramic heating belt and is externally connected with heat treatment control equipment.
Furthermore, the heating device also comprises heat insulation cotton, and the heat insulation cotton is wrapped on the outer surface of the ceramic heating belt.
Further, the pressure pipeline pipe fitting thermal state strain measurement experiment table further comprises a laser emitter and a laser sensor; the laser emitter and the laser sensor are oppositely arranged on two sides of the experiment table base, and the laser sensor is used for receiving laser emitted by the laser emitter; the first pipe clamp, the second pipe clamp and the push disc are located in the same axial direction, through holes used for penetrating laser are formed in the first pipe clamp and the second pipe clamp, and the laser emitter and the laser sensor are arranged right opposite to the through holes.
Further, the first pipe clamp and the second pipe clamp each comprise two semicircular pipe clamps and two pairs of bolts and nuts; the two semicircular pipe hoops are spliced into a first circular pipe hoop or a second circular pipe hoop, and the connection position is fixedly connected through a bolt and a nut; the through hole is arranged on the semicircular pipe hoop at the upper end.
Furthermore, a groove is formed in the bench surface of the experiment table base below the first pipe hoop, and the semicircular pipe hoop at the lower end of the first pipe hoop is fixed in the groove; the bench surface of the experiment table base below the second pipe hoop is provided with a guide groove, the semicircular pipe hoop at the lower end of the second pipe hoop is provided with a roller, and the roller can slide in the guide groove.
Furthermore, the inner diameter of the first pipe clamp and the second pipe clamp is equal to the outer diameter of the tightening part of the pipe fitting to be measured.
Furthermore, a plurality of clamping blocks are welded on the outer wall of the pipe fitting to be tested and used for clamping the side wall of the first pipe hoop or the second pipe hoop.
Furthermore, a reinforcing rib plate is connected between the lower part of the table top of the experiment table base and the side wall of the experiment table base.
Furthermore, the pipe fitting to be tested comprises a straight pipe, a reducing pipe, a straight pipe with a valve and a straight pipe with a tee joint.
The utility model has the advantages that:
the utility model provides a pipeline under pressure pipe fitting thermal state strain measurement laboratory bench, the one end of pipe fitting will await measuring is fixed on the mesa of laboratory bench base through first ferrule, the second ferrule is fixed on the other end of pipe fitting that awaits measuring, and the second ferrule can move on the mesa, then the tip that axial motion and extrusion pipe fitting that awaits measuring are done to the thrust pushing tray through hydraulic system promotion, make the pipe fitting that awaits measuring receive thrust, the station heating of awaiting measuring of pipe fitting that awaits measuring is given to rethread heating device, and finally, the welding formula high temperature strain gauge through the multiple spot arrangement and with the external strain gauge of high temperature strain gauge measurement pipe fitting that awaits measuring, bring the strain value into formula calculation and obtain the stress value and integrate the stress value of multiple spot into the trend graph, and compare with the calculation cloud picture under the same condition, verify the calculation accuracy of finite element, the finite element calculated result is revised in the feedback simultaneously.
Drawings
Fig. 1 is a schematic structural diagram of the present invention.
Fig. 2 isbase:Sub>A sectional viewbase:Sub>A-base:Sub>A of fig. 1.
Fig. 3 is a sectional view taken along line B-B of fig. 1.
The reference numbers in the figures are: 1. a bench base; 2. reinforcing rib plates; 3a, a first pipe hoop; 3b, a second pipe hoop; 31. a semicircular pipe hoop; 4. a pipe fitting to be tested; 5. a clamping block; 6. a nut; 7. a bolt; 8. a laser transmitter; 9. a temperature control thermocouple; 10. a high temperature strain gauge; 11. a ceramic heating zone; 12. heat preservation cotton; 13. a roller; 14. pushing the disc; 15. a hydraulic system; 16. a laser sensor; 17. a through hole; 20. a guide groove.
Detailed Description
The present invention is described below with reference to the accompanying drawings, and the specific embodiments described herein are only used for illustrating and explaining the present invention, and are not used for limiting the present invention, and various modifications and improvements made by those skilled in the art to the technical solution of the present invention should fall into the protection scope of the present invention without departing from the design spirit of the present invention.
As shown in fig. 1 to fig. 3, the pressure pipe fitting thermal state strain measurement experiment table of the present embodiment includes a pipe fitting 4 to be measured, an experiment table base 1, a first pipe clamp 3a, a second pipe clamp 3b, a hydraulic system 15, a push disc 14, a heating device, and a plurality of high temperature strain gauges 10.
The first pipe clamp 3a and the second pipe clamp 3b are oppositely arranged on two sides of the table top of the experiment table base 1, the first pipe clamp 3a is fixedly arranged on the table top, and the second pipe clamp 3b can slide on the table top. The two ends of the pipe fitting 4 to be measured are respectively fixed on the first pipe hoop 3a and the second pipe hoop 3 b.
Specifically, the first pipe clamp 3a and the second pipe clamp 3b each include two semicircular pipe clamps 31 and two pairs of bolts 7 and nuts 6. The two semicircular pipe hoops 31 are spliced into a first circular pipe hoop 3a or a second circular pipe hoop 3b, and the connection position is fixedly connected through a bolt 7 and a nut 6. When putting into the pipe fitting 4 that awaits measuring, can take off the semicircle ferrule 31 of upper end, then put into the pipe fitting 4 that awaits measuring, later will take off again the semicircle ferrule 31 of upper end and install to connect through bolt 7 and nut 6. And the inner diameters of the first pipe clamp 3a and the second pipe clamp 3b are equal to the outer diameter of the clamped part of the pipe fitting 4 to be tested, so that the pipe fitting 4 to be tested can be firmly fixed on the first pipe clamp 3a or the second pipe clamp 3 b. In addition, the outer wall of the pipe fitting 4 to be tested is welded with a plurality of clamping blocks 5 for clamping the side walls of the first pipe hoop 3a or the second pipe hoop 3b, wherein the clamping blocks 5 positioned at the first pipe hoop 3a can clamp the first pipe hoop 3a from the left and the right, and the clamping blocks 5 positioned at the second pipe hoop 3b can clamp the second pipe hoop 3b from the left, so that the stability can be further improved.
The table surface of the experiment table base 1 positioned below the first pipe hoop 3a is provided with a groove, and a semicircular pipe hoop 31 at the lower end of the first pipe hoop 3a is fixed in the groove. The table surface of the experiment table base 1 positioned below the second pipe hoop 3b is provided with a guide groove 20, the semicircular pipe hoop 31 at the lower end of the second pipe hoop 3b is provided with a roller 13, and the roller 13 can slide in the guide groove 20.
The hydraulic system 15 and the push disc 14 are arranged on the table top of the experiment table base 1 and located on the outer side of the second pipe hoop 3b, the hydraulic system 15 is connected with the push disc 14, an expansion gap is reserved between the pipe fitting 4 to be tested and the push disc 14, and the hydraulic system 15 enables the push disc 14 to do linear motion along the axis of the push disc 14 and extrude the end portion of the pipe fitting 4 to be tested. In general, a hydraulic system functions to increase a force by changing a pressure. A complete hydraulic system consists of five parts, namely a power element, an actuator, a control element, an auxiliary element (attachment) and hydraulic oil. Hydraulic systems can be divided into two categories: hydraulic transmission systems and hydraulic control systems. The hydraulic transmission system mainly functions to transmit power and motion, and the hydraulic transmission system is mainly referred to as a hydraulic transmission system, while the hydraulic system 15 of the embodiment can adaptively select any one of the existing hydraulic systems which can generate axial thrust.
In order to ensure that the push disc 14, the first pipe clamp 3a and the second pipe clamp 3b are in the same axial direction during testing, the pressure pipeline fitting thermal strain measurement experiment table further comprises a laser emitter 8 and a laser sensor 16. Laser emitter 8 and laser sensor 16 are established relatively in the both sides of laboratory bench base 1, and laser sensor 16 is used for receiving the laser that laser emitter 8 sent, and when laser sensor 16 received the laser, the pilot lamp on the laser sensor 16 is usually bright. The first pipe clamp 3a, the second pipe clamp 3b and the push disc 14 are located in the same axial direction, through holes 17 used for passing laser are formed in semicircular pipe clamps 31 at the upper ends of the first pipe clamp 3a and the second pipe clamp 3b, and the laser emitter 8 and the laser sensor 16 are arranged right opposite to the through holes 17. When the laser emitted by the laser emitter 8 can pass through the through holes 17 on the first pipe clamp 3a and the second pipe clamp 3b and irradiate on the laser sensor 16, it indicates that the push disk 14, the first pipe clamp 3a and the second pipe clamp 3b are in the same axial direction, so that the end part of the pipe fitting 4 to be measured is stressed uniformly.
The heating device is arranged on the pipe wall of the pipe fitting 4 to be heated (to-be-measured point) and used for heating the pipe fitting 4 to be measured. Specifically, the heating device comprises a ceramic heating belt 11, a temperature control thermocouple 9 and heat preservation cotton 12. Wherein, the winding of ceramic heating area 11 sets up on the pipe wall that awaits measuring pipe fitting 4 waited to heat, and ceramic heating area 11 external thermal treatment controlgear for ceramic heating area 11 heats. The temperature control thermocouple 9 is arranged at the edge of the ceramic heating belt 11, and the temperature control thermocouple 9 is externally connected with heat treatment control equipment for controlling the temperature. The heat preservation cotton 12 wraps the outer surface of the ceramic heating belt 11, and the influence of the outside on the temperature of the pipe fitting 4 to be measured is reduced.
The high-temperature strain gauges 10 are welded at the point to be measured of the pipe fitting 4 to be measured, and the high-temperature strain gauges 10 are externally connected with a strain measuring instrument and used for measuring strain values of the point to be measured.
In order to provide the steadiness, be connected with deep floor 2 between 1 lateral wall of laboratory bench base 1 mesa below of laboratory bench base. The utility model discloses a pipe fitting 4 that awaits measuring includes straight tube, reducing pipe, the straight tube of taking the valve and takes the tee bend straight tube etc. and test range is wide.
During the use, weld fixture block 5 on the pipe fitting 4 that awaits measuring, install according to the fixed mode of fig. 1 to guarantee that laser emitter 8's laser passes through the through-hole 17 of first ferrule 3a and second ferrule 3b, and by laser sensor 16 perception and bright warning light. Welding a high-temperature strain gauge 10 on a point to be measured, winding a ceramic heating belt 11 on the point to be measured of the pipe fitting 4 to be measured, placing a temperature control thermocouple 9 at the position, close to the edge, of the ceramic heating belt 11, and externally connecting the ceramic heating belt 11 and the temperature control thermocouple 9 with heat treatment control equipment. The outer side of the ceramic heating belt 11 is wrapped with a layer of heat preservation cotton 12 which completely covers the ceramic heating belt 11. Starting heat treatment control equipment, setting heating temperature, keeping the temperature for a certain time after heating to a preset temperature, then setting the zero point of strain measurement at the moment, starting a hydraulic system 15, applying axial force (thrust) to the end part of the pipe fitting 4 to be measured, keeping the axial force for a period of time, measuring the thermal state strain of the pipe fitting 4 to be measured through a welding type high-temperature strain gauge 10 arranged at multiple points and a strain measuring instrument externally connected with the high-temperature strain gauge 10, substituting the strain value into a formula to calculate to obtain a stress value, integrating the stress values of the multiple points into a trend graph, comparing the trend graph with a calculated cloud graph under the same condition, verifying the calculation accuracy of a finite element, and simultaneously feeding back and correcting a finite element calculation result.
Claims (10)
1. The utility model provides a pipeline under pressure pipe fitting thermal state strain measurement laboratory bench, includes pipe fitting (4) and laboratory bench base (1) that await measuring, its characterized in that: the device also comprises a first pipe hoop (3 a), a second pipe hoop (3 b), a hydraulic system (15), a push disc (14), a heating device and a plurality of high-temperature strain gauges (10); the first pipe clamp (3 a) and the second pipe clamp (3 b) are oppositely arranged on two sides of the table top of the experiment table base (1), the first pipe clamp (3 a) is fixedly arranged on the table top of the experiment table base (1), and the second pipe clamp (3 b) can slide on the table top of the experiment table base (1); two ends of the pipe fitting (4) to be tested are respectively fixed on the first pipe hoop (3 a) and the second pipe hoop (3 b); the hydraulic system (15) and the push disc (14) are arranged on the table top of the experiment table base (1) and located at the outer side of the second pipe hoop (3 b), the hydraulic system (15) is connected with the push disc (14), and the hydraulic system (15) can enable the push disc (14) to do linear motion along the axis of the push disc and extrude the end part of the pipe fitting (4) to be measured; the heating device is arranged on the pipe wall to be heated of the pipe fitting (4) to be heated and is used for heating the pipe fitting (4) to be heated; the high-temperature strain gauges (10) are welded at a point to be measured of the pipe fitting (4) to be measured, and the high-temperature strain gauges (10) are externally connected with a strain measuring instrument and used for measuring a strain value of the point to be measured.
2. The pressure pipe fitting thermal state strain measurement experiment table according to claim 1, wherein: the heating device comprises a ceramic heating belt (11) and a temperature control thermocouple (9); the ceramic heating belt (11) is wound on the pipe wall to be heated of the pipe fitting (4) to be heated, and the ceramic heating belt (11) is externally connected with heat treatment control equipment and used for heating the ceramic heating belt (11); the temperature control thermocouple (9) is arranged at the edge of the ceramic heating belt (11), and the temperature control thermocouple (9) is externally connected with heat treatment control equipment.
3. The pressure pipe fitting thermal state strain measurement experiment table according to claim 2, wherein: the heating device further comprises heat preservation cotton (12), and the heat preservation cotton (12) is wrapped on the outer surface of the ceramic heating belt (11).
4. The pressure pipe fitting thermal state strain measurement experiment table according to claim 1, wherein: the device also comprises a laser transmitter (8) and a laser sensor (16); the laser emitter (8) and the laser sensor (16) are oppositely arranged on two sides of the experiment table base (1), and the laser sensor (16) is used for receiving laser emitted by the laser emitter (8); first ferrule (3 a), second ferrule (3 b) and push away set (14) and be in same axial, all be equipped with through-hole (17) that are used for passing laser on first ferrule (3 a) and the second ferrule (3 b), laser emitter (8) and laser sensor (16) just set up through-hole (17).
5. The pressure pipe fitting thermal state strain measurement experiment table according to claim 4, wherein: the first pipe clamp (3 a) and the second pipe clamp (3 b) respectively comprise two semicircular pipe clamps (31) and two pairs of bolts (7) and nuts (6); the two semicircular pipe hoops (31) are spliced into a first circular pipe hoop (3 a) or a second circular pipe hoop (3 b), and the connection part is fixedly connected with a nut (6) through a bolt (7); the through hole (17) is arranged on the semicircular pipe hoop (31) at the upper end.
6. The pressure pipe fitting thermal state strain measurement experiment table according to claim 5, wherein: a groove is formed in the table surface of the experiment table base (1) below the first pipe hoop (3 a), and a semicircular pipe hoop (31) at the lower end of the first pipe hoop (3 a) is fixed in the groove; the experiment table base (1) table surface below the second pipe hoop (3 b) is provided with a guide groove (20), the semicircular pipe hoop (31) at the lower end of the second pipe hoop (3 b) is provided with a roller (13), and the roller (13) can slide in the guide groove (20).
7. The pressure pipe fitting thermal state strain measurement experiment table according to claim 1, wherein: the inner diameters of the first pipe clamp (3 a) and the second pipe clamp (3 b) are equal to the outer diameter of the clamped part of the pipe fitting (4) to be measured.
8. The pressure pipe fitting thermal state strain measurement experiment table according to claim 7, wherein: the outer wall of the pipe fitting (4) to be measured is welded with a plurality of clamping blocks (5), and the clamping blocks (5) are used for clamping the side wall of the first pipe hoop (3 a) or the second pipe hoop (3 b).
9. The pressure pipe fitting thermal state strain measurement experiment table according to claim 1, wherein: and a reinforcing rib plate (2) is connected between the lower part of the table top of the experiment table base (1) and the side wall of the experiment table base (1).
10. The pressure pipe fitting thermal state strain measurement experiment table according to claim 1, wherein: the pipe fitting (4) to be tested comprises a straight pipe, a reducing pipe, a straight pipe with a valve and a straight pipe with a tee joint.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221221698.6U CN217766170U (en) | 2022-05-20 | 2022-05-20 | Thermal state strain measurement experiment table for pressure pipeline pipe fitting |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221221698.6U CN217766170U (en) | 2022-05-20 | 2022-05-20 | Thermal state strain measurement experiment table for pressure pipeline pipe fitting |
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| CN217766170U true CN217766170U (en) | 2022-11-08 |
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| CN202221221698.6U Active CN217766170U (en) | 2022-05-20 | 2022-05-20 | Thermal state strain measurement experiment table for pressure pipeline pipe fitting |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117091476A (en) * | 2023-10-17 | 2023-11-21 | 普瑞奇科技（北京）股份有限公司 | Control assembly tester based on vacuum oil filter |
-
2022
- 2022-05-20 CN CN202221221698.6U patent/CN217766170U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117091476A (en) * | 2023-10-17 | 2023-11-21 | 普瑞奇科技（北京）股份有限公司 | Control assembly tester based on vacuum oil filter |
| CN117091476B (en) * | 2023-10-17 | 2024-01-19 | 普瑞奇科技（北京）股份有限公司 | Control assembly tester based on vacuum oil filter |
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