CN117093030A - Temperature control system and method for low-temperature fatigue test of expansion joint of metal corrugated pipe - Google Patents
Temperature control system and method for low-temperature fatigue test of expansion joint of metal corrugated pipe Download PDFInfo
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- CN117093030A CN117093030A CN202310847848.7A CN202310847848A CN117093030A CN 117093030 A CN117093030 A CN 117093030A CN 202310847848 A CN202310847848 A CN 202310847848A CN 117093030 A CN117093030 A CN 117093030A
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- 238000009661 fatigue test Methods 0.000 title claims abstract description 27
- 239000002184 metal Substances 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000012360 testing method Methods 0.000 claims abstract description 61
- 239000007791 liquid phase Substances 0.000 claims abstract description 40
- 239000012071 phase Substances 0.000 claims abstract description 29
- 238000007599 discharging Methods 0.000 claims abstract description 25
- 230000008569 process Effects 0.000 claims description 7
- 230000004044 response Effects 0.000 claims description 6
- 230000008859 change Effects 0.000 description 2
- 230000006854 communication Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 230000007175 bidirectional communication Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/19—Control of temperature characterised by the use of electric means
- G05D23/20—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature
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- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a temperature control system and a temperature control method for a low-temperature fatigue test of a metal bellows expansion joint, wherein the system comprises a low-temperature source, a gas-phase outlet and a liquid-phase outlet; the expansion joint test piece is provided with a temperature feedback element, a gas phase emptying piece and a liquid phase discharging piece; the inlet and the outlet of the first pipeline are respectively connected with the gas phase outlet and the expansion joint test piece so as to pre-cool the gas phase outlet and the expansion joint test piece, and a first low-temperature electric valve, a second low-temperature electric valve and a pressure gauge are sequentially connected into the first pipeline along the flow direction of a medium; the inlet of the second pipeline is communicated with the liquid phase outlet, the outlet is connected between the first low-temperature electric valve and the second low-temperature electric valve, and a third low-temperature electric valve and a low-temperature pump are sequentially connected into the second pipeline along the flow direction of a medium; and the electric control box is respectively and electrically connected with the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump and the expansion joint test piece.
Description
Technical Field
The invention relates to the technical field of bellows expansion joints, in particular to a temperature control system and a temperature control method for a low-temperature fatigue test of a metal bellows expansion joint.
Background
The metal corrugated expansion joint is a key component for thermal compensation of the pressure pipeline and equipment, is used as an important component for guaranteeing stable operation of the pressure pipeline and equipment, has the functions of displacement compensation, vibration reduction, noise reduction and sealing, and is widely applied to the industrial fields of heat supply networks, oil refining, chemical industry, electric power, ships and the like. The expansion joint compensates the displacement of alternating working conditions such as pipe network temperature change, vibration and the like, bears repeated cyclic high stress, and fatigue becomes a main concern point and also becomes a weak link of the pipe network. In a sense, the fatigue life of the bellows expansion joint determines the remaining life of the entire pipe network. The reliability of the low-temperature application of the bellows expansion joint is verified by a fatigue test under the low-temperature working condition.
At present, for a low-temperature working condition fatigue test of a metal bellows expansion joint, an environment box is generally adopted for test temperature adjustment. According to the temperature required by the test, parameter setting is carried out on an operation interface of the environment box, and the adjustment of the ambient temperature of the expansion joint test piece can be realized. However, the low-temperature environment box has high manufacturing cost, limited box space size and poor compatibility, and meanwhile, the actual temperature inside the expansion joint test piece cannot be obtained.
Disclosure of Invention
The invention aims to provide a temperature control system and a temperature control method for a low-temperature fatigue test of a metal bellows expansion joint, which are used for solving the problems that a current low-temperature environment box is high in manufacturing cost, limited in box size and poor in compatibility, and meanwhile, the actual temperature inside an expansion joint test piece cannot be obtained.
The above object of the present invention can be achieved by the following technical solutions:
the invention provides a temperature control system for a low-temperature fatigue test of a metal bellows expansion joint, which comprises the following components:
a cryogenic source having a gas phase outlet and a liquid phase outlet;
the expansion joint test piece is provided with a temperature feedback element, a gas phase emptying piece and a liquid phase discharging piece;
the inlet and the outlet of the first pipeline are respectively connected with the gas phase outlet and the expansion joint test piece so as to pre-cool the gas phase outlet and the expansion joint test piece, and a first low-temperature electric valve, a second low-temperature electric valve and a pressure gauge are sequentially connected into the first pipeline along the flow direction of a medium;
the inlet of the second pipeline is communicated with the liquid phase outlet, the outlet is connected between the first low-temperature electric valve and the second low-temperature electric valve, and a third low-temperature electric valve and a low-temperature pump are sequentially connected into the second pipeline along the flow direction of a medium;
and the electric control box is respectively and electrically connected with the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump and the expansion joint test piece.
Preferably, the electric cabinet includes:
the PLC is respectively and electrically connected with the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump and the expansion joint test piece;
the touch screen is electrically connected with the PLC;
and in a working state, the PLC can respond to the instruction of the touch screen and respectively control the working parameters of the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump, the gas phase emptying piece and the liquid phase discharging piece according to the feedback signal of the temperature feedback element so as to complete temperature control.
Preferably, the PLC controller is electrically connected to the pressure gauge so as to directly collect the pressure signal in the first pipeline.
Preferably, the pressure gauge is a digital display pressure gauge.
Preferably, the gas phase evacuation member comprises an evacuation pipeline and an evacuation valve arranged in the evacuation pipeline, wherein the evacuation valve is electrically connected with the PLC controller so as to be capable of communicating with or cutting off the evacuation pipeline in response to a control command thereof.
Preferably, the liquid phase discharging part includes a liquid phase discharging pipe and a liquid phase discharging valve provided in the liquid phase discharging pipe, the liquid phase discharging valve being electrically connected to the PLC controller to be able to communicate or cut off the liquid phase discharging pipe in response to a control command thereof.
Preferably, the opening degree of the first low-temperature electric valve is adjustable.
Preferably, the opening degree of the second low-temperature electric valve is adjustable.
Preferably, the opening degree of the third low-temperature electric valve is adjustable.
The invention also provides a temperature control method for the low-temperature fatigue test of the metal bellows expansion joint, which comprises the following steps of:
a precooling pipeline is formed by the gas phase outlet, the first low-temperature electric valve, the second low-temperature electric valve, the pressure gauge, the expansion joint test piece and the electric cabinet;
a low-temperature pipeline is formed by the liquid phase outlet, the third low-temperature electric valve, the low-temperature pump, the second low-temperature electric valve, the pressure gauge, the expansion joint test piece and the electric control box;
setting precooling parameters based on the electric cabinet, and precooling the expansion joint test piece by utilizing the precooling pipeline according to the precooling parameters;
when the precooling temperature of the expansion joint test piece reaches the set temperature and meets the low-temperature maintaining time, the electric cabinet cuts off the precooling pipeline and opens the low-temperature pipeline;
the working parameters of the third low-temperature electric valve, the low-temperature pump and the second low-temperature electric valve are adjusted in real time according to the feedback signals of the temperature feedback element so as to complete low-temperature control;
in the precooling process, the low-temperature medium can be emptied by using the gas-phase emptying piece; in the low-temperature control process, the low-temperature medium can be discharged or stored in the expansion joint test piece by utilizing the liquid-phase discharge piece to complete temperature control.
The invention has at least the following characteristics and advantages:
the invention provides an intelligent temperature control system composed of a precooling pipeline system and a low-temperature pipeline system, which can realize low-temperature fatigue tests of expansion joints with different sizes by combining a conventional hydraulic press. The intelligent temperature control system has the remarkable advantages of low cost, easy maintenance, flexible installation, intelligent temperature adjustment and the like, and meanwhile, the intelligent temperature control system can acquire the actual temperature inside the expansion joint test piece, so that the test temperature is more accurate.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a temperature control system for low temperature fatigue test of a metal bellows expansion joint according to the present invention.
Reference numerals and description:
1. a low temperature source; 2. an expansion joint test piece; 3. a first low temperature electrically operated valve; 4. the second low-temperature electric valve; 5. a third low-temperature electric valve; 6. a cryogenic pump; 7. a digital display pressure gauge; 8. an electric control box.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is apparent that the embodiments described below are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Embodiment one
The invention provides a temperature control system for a low-temperature fatigue test of a metal corrugated pipe expansion joint, which is shown in fig. 1, and comprises a low-temperature source, an expansion joint test piece, a first pipeline, a second pipeline and an electric cabinet.
Specifically, the cryogenic source has a gas phase outlet and a liquid phase outlet; the expansion joint test piece is provided with a temperature feedback element, a gas phase emptying piece and a liquid phase discharging piece; the inlet and the outlet of the first pipeline are respectively connected with the gas phase outlet and the expansion joint test piece so as to pre-cool the gas phase outlet and the expansion joint test piece, and a first low-temperature electric valve, a second low-temperature electric valve and a pressure gauge are sequentially connected into the first pipeline along the flow direction of a medium; the inlet of the second pipeline is communicated with the liquid phase outlet, the outlet is connected between the first low-temperature electric valve and the second low-temperature electric valve, and a third low-temperature electric valve and a low-temperature pump are sequentially connected into the second pipeline along the flow direction of the medium; the electric control box is electrically connected with the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump and the expansion joint test piece respectively.
In some embodiments, the electric cabinet includes a PLC controller and a touch screen. Specifically, the PLC is electrically connected with the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump and the expansion joint test piece respectively; the touch screen is electrically connected with the PLC; in the working state, the PLC can respond to the instruction of the touch screen and respectively control the working parameters of the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump, the gas-phase emptying piece and the liquid-phase discharging piece according to the feedback signal of the temperature feedback element so as to complete temperature control.
In some embodiments, the PLC controller and the pressure gauge are electrically connected to enable direct acquisition of the pressure signal in the first line. Further, the pressure gauge is a digital display pressure gauge.
In some embodiments, the gas phase evacuation member includes an evacuation line and an evacuation valve disposed in the evacuation line, the evacuation valve being electrically connected to the PLC controller to enable communication or disconnection of the evacuation line in response to control commands thereof.
In some embodiments, the liquid phase discharging member includes a liquid phase discharging pipe and a liquid phase discharging valve provided in the liquid phase discharging pipe, the liquid phase discharging valve being electrically connected to the PLC controller to be able to communicate or shut off the liquid phase discharging pipe in response to a control instruction thereof.
In some embodiments, the opening degree of the first cryogenic electric valve is adjustable. In some embodiments, the opening degree of the second cryogenic electric valve is adjustable. In some embodiments, the opening degree of the third cryogenic electric valve is adjustable.
The invention provides an intelligent temperature control system composed of a precooling pipeline system and a low-temperature pipeline system, which can realize low-temperature fatigue tests of expansion joints with different sizes by combining a conventional hydraulic press. The intelligent temperature control system has the remarkable advantages of low cost, easy maintenance, flexible installation, intelligent temperature adjustment and the like, and meanwhile, the intelligent temperature control system can acquire the actual temperature inside the expansion joint test piece, so that the test temperature is more accurate.
Second embodiment
The invention also provides a temperature control method for the low-temperature fatigue test of the metal bellows expansion joint, which comprises the following steps of:
s1, a gas phase outlet, a first low-temperature electric valve, a second low-temperature electric valve, a pressure gauge, an expansion joint test piece and an electric cabinet are utilized to form a precooling pipeline;
s2, a liquid phase outlet, a third low-temperature electric valve, a low-temperature pump, a second low-temperature electric valve, a pressure gauge, an expansion joint test piece and an electric cabinet are utilized to form a low-temperature pipeline;
s3, setting precooling parameters based on an electric cabinet, and precooling the expansion joint test piece by utilizing a precooling pipeline according to the precooling parameters;
s4, when the precooling temperature of the expansion joint test piece reaches the set temperature and the low-temperature maintaining time is met, the electric cabinet cuts off the precooling pipeline and opens the low-temperature pipeline;
s5, working parameters of the third low-temperature electric valve, the low-temperature pump and the second low-temperature electric valve are adjusted in real time according to feedback signals of the temperature feedback element so as to complete low-temperature control;
in the precooling process, the low-temperature medium can be emptied by utilizing a gas-phase emptying piece; in the low-temperature control process, the low-temperature medium can be discharged or stored in the expansion joint test piece by utilizing the liquid-phase discharge piece to complete temperature control.
The invention is further described and illustrated by the following example, please refer to fig. 1:
the invention consists of a precooling pipeline system and a low-temperature pipeline system.
The precooling pipeline system consists of a precooling pipeline consisting of a gaseous low-temperature source, a low-temperature electric valve and a pipeline pipe fitting, an electric cabinet and an expansion joint test piece;
the low-temperature pipeline system consists of a low-temperature pipeline consisting of a liquid low-temperature source, a low-temperature electric valve and a pipeline pipe fitting, an electric cabinet, a low-temperature pump and an expansion joint test piece.
The low-temperature electric valve, the low-temperature pump, the digital display pressure gauge, the expansion joint test piece temperature feedback element and the like are communicated with a PLC controller of the electric cabinet through a communication cable, and the PLC controller is connected with the touch screen through the cable and performs bidirectional communication. Parameters such as temperature and pressure of the expansion joint low-temperature fatigue test are manually set through a touch screen of the electric cabinet, and the PLC controls the low-temperature electric valve and the low-temperature pump by sensing the change of signals of a feedback element of the expansion joint test, so that the intelligent control of the temperature of the metal corrugated expansion joint low-temperature fatigue test is realized.
Specifically, as shown in fig. 1, a gas phase outlet a of a low-temperature source 1, a first low-temperature electric valve 3, a second low-temperature electric valve 4, a digital display pressure gauge 7, an expansion joint test piece 2 and an electric cabinet 8 form a low-temperature test precooling pipeline together. The low temperature source 1 liquid phase outlet B, the third low temperature electric valve 5, the low temperature pump 6, the second low temperature electric valve 4, the digital display pressure gauge 7, the expansion joint test piece 2 and the electric control box 8 form a low temperature test low temperature pipeline together. The low temperature test is that precooling of an expansion joint test piece is carried out firstly, precooling temperature holding time, test temperature and test pressure are set through a touch screen of an electric cabinet 8, the electric cabinet 8 automatically adjusts the size and opening and closing of a low-temperature electric valve according to a feedback value of a temperature feedback element of the expansion joint test piece 2, after the precooling temperature reaches the set temperature and meets the low-temperature holding time, the electric cabinet 8 cuts off a precooling pipeline system, controls a third low-temperature electric valve 5 and a low-temperature pump 6 to be started, and starts the low-temperature pipeline system, and the electric cabinet 8 controls the opening and closing of the low-temperature electric valve and the flow of the low-temperature pump in real time according to the temperature feedback element of the expansion joint test piece 2 to realize stable control of the temperature and the internal pressure of the expansion joint test piece in the whole low-temperature test process.
The present invention is not limited to the above embodiments, but is capable of modification and variation in all aspects, including those of ordinary skill in the art, without departing from the spirit and scope of the present invention.
Claims (10)
1. A temperature control system for a low temperature fatigue test of a metal bellows expansion joint, comprising:
a cryogenic source having a gas phase outlet and a liquid phase outlet;
the expansion joint test piece is provided with a temperature feedback element, a gas phase emptying piece and a liquid phase discharging piece;
the inlet and the outlet of the first pipeline are respectively connected with the gas phase outlet and the expansion joint test piece so as to pre-cool the gas phase outlet and the expansion joint test piece, and a first low-temperature electric valve, a second low-temperature electric valve and a pressure gauge are sequentially connected into the first pipeline along the flow direction of a medium;
the inlet of the second pipeline is communicated with the liquid phase outlet, the outlet is connected between the first low-temperature electric valve and the second low-temperature electric valve, and a third low-temperature electric valve and a low-temperature pump are sequentially connected into the second pipeline along the flow direction of a medium;
and the electric control box is respectively and electrically connected with the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump and the expansion joint test piece.
2. The temperature control system for a low temperature fatigue test of a metal bellows expansion joint according to claim 1, wherein the electric cabinet includes:
the PLC is respectively and electrically connected with the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump and the expansion joint test piece;
the touch screen is electrically connected with the PLC;
and in a working state, the PLC can respond to the instruction of the touch screen and respectively control the working parameters of the first low-temperature electric valve, the second low-temperature electric valve, the third low-temperature electric valve, the low-temperature pump, the gas phase emptying piece and the liquid phase discharging piece according to the feedback signal of the temperature feedback element so as to complete temperature control.
3. The temperature control system for low temperature fatigue test of metal bellows expansion joint according to claim 2, wherein the PLC controller and the pressure gauge are electrically connected to directly collect the pressure signal in the first pipeline.
4. The temperature control system for low-temperature fatigue test of metal bellows expansion joint according to claim 3, wherein the pressure gauge is a digital display pressure gauge.
5. The temperature control system for a low temperature fatigue test of a metal bellows expansion joint according to claim 2, wherein the gas phase evacuation member includes an evacuation line and an evacuation valve provided in the evacuation line, the evacuation valve being electrically connected to the PLC controller so as to be capable of communicating with or shutting off the evacuation line in response to a control instruction thereof.
6. The temperature control system for a low temperature fatigue test of a metal bellows expansion joint according to claim 5, wherein the liquid phase discharging member includes a liquid phase discharging pipe and a liquid phase discharging valve provided in the liquid phase discharging pipe, the liquid phase discharging valve being electrically connected with the PLC controller so as to be capable of communicating or shutting off the liquid phase discharging pipe in response to a control instruction thereof.
7. The temperature control system for a low temperature fatigue test of a metal bellows expansion joint according to claim 6, wherein an opening degree of the first low temperature electric valve is adjustable.
8. The temperature control system for a low-temperature fatigue test of a metal bellows expansion joint according to claim 7, wherein an opening degree of the second low-temperature electric valve is adjustable.
9. The temperature control system for low-temperature fatigue test of metal bellows expansion joint according to claim 8, wherein the opening degree of the third low-temperature electric valve is adjustable.
10. A temperature control method for a low temperature fatigue test of a metal bellows expansion joint, characterized in that the following steps are performed by using the temperature control system for a low temperature fatigue test of a metal bellows expansion joint according to any one of claims 1 to 9:
a precooling pipeline is formed by the gas phase outlet, the first low-temperature electric valve, the second low-temperature electric valve, the pressure gauge, the expansion joint test piece and the electric cabinet;
a low-temperature pipeline is formed by the liquid phase outlet, the third low-temperature electric valve, the low-temperature pump, the second low-temperature electric valve, the pressure gauge, the expansion joint test piece and the electric control box;
setting precooling parameters based on the electric cabinet, and precooling the expansion joint test piece by utilizing the precooling pipeline according to the precooling parameters;
when the precooling temperature of the expansion joint test piece reaches the set temperature and meets the low-temperature maintaining time, the electric cabinet cuts off the precooling pipeline and opens the low-temperature pipeline;
the working parameters of the third low-temperature electric valve, the low-temperature pump and the second low-temperature electric valve are adjusted in real time according to the feedback signals of the temperature feedback element so as to complete low-temperature control;
in the precooling process, the low-temperature medium can be emptied by using the gas-phase emptying piece; in the low-temperature control process, the low-temperature medium can be discharged or stored in the expansion joint test piece by utilizing the liquid-phase discharge piece to complete temperature control.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310847848.7A CN117093030A (en) | 2023-07-11 | 2023-07-11 | Temperature control system and method for low-temperature fatigue test of expansion joint of metal corrugated pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310847848.7A CN117093030A (en) | 2023-07-11 | 2023-07-11 | Temperature control system and method for low-temperature fatigue test of expansion joint of metal corrugated pipe |
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| Publication Number | Publication Date |
|---|---|
| CN117093030A true CN117093030A (en) | 2023-11-21 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310847848.7A Pending CN117093030A (en) | 2023-07-11 | 2023-07-11 | Temperature control system and method for low-temperature fatigue test of expansion joint of metal corrugated pipe |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117093030A (en) |
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2023
- 2023-07-11 CN CN202310847848.7A patent/CN117093030A/en active Pending
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