CN111425688B - Structure and method for realizing low-temperature pipeline system pressure oscillation regulation and control - Google Patents
Structure and method for realizing low-temperature pipeline system pressure oscillation regulation and control Download PDFInfo
- Publication number
- CN111425688B CN111425688B CN202010151716.7A CN202010151716A CN111425688B CN 111425688 B CN111425688 B CN 111425688B CN 202010151716 A CN202010151716 A CN 202010151716A CN 111425688 B CN111425688 B CN 111425688B
- Authority
- CN
- China
- Prior art keywords
- low
- temperature
- regulation
- oscillation
- pipeline
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/04—Devices damping pulsations or vibrations in fluids
- F16L55/045—Devices damping pulsations or vibrations in fluids specially adapted to prevent or minimise the effects of water hammer
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Pipeline Systems (AREA)
Abstract
The utility model provides a realize structure and method of cryogenic piping system pressure oscillation regulation and control, includes that the built-in cryogenic liquid storage tank that has cryogenic liquid is provided with the open end and the cryogenic liquid storage tank links to each other the other end confined cryogenic piping in cryogenic liquid storage tank, installs the inside pressure oscillation regulation and control module of adjustment system on cryogenic piping, cryogenic piping is located normal atmospheric temperature environment, and cryogenic piping forms along the axial temperature gradient distribution of pipe jointly with the open end of placing cryogenic liquid storage tank in to induce the inside pressure oscillation of system. According to the invention, the low-temperature pipeline with the opening end connected with the low-temperature liquid storage tank and the other end closed is arranged in the low-temperature liquid storage tank, and the pressure oscillation regulation and control module in the regulation system is arranged on the low-temperature pipeline, so that the unfavorable pressure oscillation in the low-temperature pipeline system can be effectively inhibited by regulating the position of the oscillation regulation and control module, and the low-temperature pipeline system has the advantages of simple structure, easiness in realization, capability of meeting the requirements of different regulation and control effects, high regulation and control speed and reliable performance.
Description
Technical Field
The invention relates to a pipeline pressure regulation structure and a method, in particular to a structure and a method for realizing low-temperature pipeline system pressure oscillation regulation.
Background
The Taconis oscillator system is the simplest thermo-acoustic vibrator and consists of a cryogenic liquid tank and a cryogenic piping system. When the open section of the semi-enclosed ductwork is in a cryogenic environment while the enclosed section is maintained at ambient temperature, a temperature distribution between the hot and cold ends develops and oscillations may occur within the pipe. The driving force for the Taconis oscillation is provided by the temperature gradient in the wall direction. Taconis oscillations are widely present in cryogenic engineering measurements and cryogenic liquid storage systems. Taconis oscillation in the cryogenic system is mostly harmful, and on one hand, the Taconis oscillation greatly increases heat leakage loss in the cryogenic pipeline system; on the other hand, the Taconis oscillation may interfere with the liquid level and pressure measurement process in a low temperature environment.
Disclosure of Invention
The invention aims to provide a structure and a method for realizing the pressure oscillation regulation and control of a low-temperature pipeline system, which have simple regulation and control structure, are easy to realize, can meet the requirements of different regulation and control effects, and have high regulation and control speed and reliable performance.
In order to achieve the above purpose, the structure for regulating and controlling pressure oscillation of a cryogenic pipeline system according to the present invention comprises a cryogenic liquid storage tank with a cryogenic liquid inside, a cryogenic pipeline with an open end connected with the cryogenic liquid storage tank and a closed end is arranged in the cryogenic liquid storage tank, a module for regulating and controlling pressure oscillation inside the system is installed on the cryogenic pipeline, the cryogenic pipeline is located in a normal temperature environment, and the cryogenic pipeline and the open end of the cryogenic liquid storage tank jointly form temperature gradient distribution along the axial direction of a pipe, so as to induce pressure oscillation inside the system.
The oscillation regulation and control module is installed at a low-temperature section of the temperature gradient of the low-temperature pipeline to realize zero oscillation of pressure in the low-temperature pipeline system.
The oscillation regulation and control module adopts an expansion regulation and control element or a contraction regulation and control element;
the oscillation regulation and control module is installed at the maximum point of the temperature gradient slope of the low-temperature pipeline, and the inner diameter ratio of the adopted expansion regulation and control element to the low-temperature pipeline is more than 1.4, so that pressure zero oscillation in the low-temperature pipeline system is realized.
The oscillation regulation and control module is installed at the maximum point of the temperature gradient slope of the low-temperature pipeline, and the inner diameter ratio of the adopted contraction regulation and control element to the low-temperature pipeline is less than 0.35, so that pressure zero oscillation in the low-temperature pipeline system is realized.
The oscillation regulation and control module is installed at a temperature gradient high-temperature section of the low-temperature pipeline, and the inner diameter ratio of the adopted expansion regulation and control element to the low-temperature pipeline is less than 1.4, so that pressure zero oscillation in the low-temperature pipeline system is realized.
The oscillation regulation and control module is installed at the temperature gradient high-temperature section of the low-temperature pipeline and realizes zero oscillation of pressure in the low-temperature pipeline system when a contraction regulation and control element is adopted.
And a buffer container is also arranged on the low-temperature pipeline between the oscillation regulation and control module and the low-temperature liquid storage tank.
The invention discloses a method for realizing pressure oscillation regulation and control of a low-temperature pipeline system, which comprises the following steps:
1) starting an oscillation regulation and control module, and measuring and recording the average pressure and pressure oscillation in the low-temperature pipeline system;
2) measuring the high-low temperature ratio, the inner diameter and the position of the temperature gradient of the low-temperature pipeline system;
3) selecting an oscillation regulation module element according to the initial conditions of the cryogenic pipeline system: an expanded regulatory element or a contracted regulatory element;
4) and determining the position of the expansion regulating element or the contraction regulating element in the pipeline according to the space requirement of the low-temperature pipeline system and the position of the temperature gradient, and determining the inner diameter of the expansion regulating element or the contraction regulating element.
The oscillation regulation and control module is arranged at a low-temperature section of the temperature gradient of the low-temperature pipeline;
the oscillation regulation and control module is arranged at the maximum point of the temperature gradient slope of the low-temperature pipeline, and the inner diameter ratio of the adopted expansion regulation and control element to the low-temperature pipeline is more than 1.4;
the oscillation regulation and control module is arranged at the maximum point of the temperature gradient slope of the low-temperature pipeline, and the inner diameter ratio of the adopted contraction type regulation and control element to the low-temperature pipeline is less than 0.35;
the oscillation regulation and control module is arranged at a temperature gradient high-temperature section of the low-temperature pipeline, and the inner diameter ratio of the adopted expansion regulation and control element to the low-temperature pipeline is less than 1.4;
the oscillation regulation and control module is arranged at the temperature gradient high-temperature section of the low-temperature pipeline, adopts a contraction regulation and control element, and can realize zero oscillation of pressure in the low-temperature pipeline system when the inner diameter ratio of the oscillation regulation and control module to the low-temperature pipeline is less than 1.
The invention has the beneficial effects that: according to the invention, the low-temperature pipeline with the opening end connected with the low-temperature liquid storage tank and the other end closed is arranged in the low-temperature liquid storage tank, and the pressure oscillation regulation and control module in the regulation system is arranged on the low-temperature pipeline, so that the unfavorable pressure oscillation in the low-temperature pipeline system can be effectively inhibited by regulating the position of the oscillation regulation and control module, and the low-temperature pipeline system has the advantages of simple structure, easiness in realization, capability of meeting the requirements of different regulation and control effects, high regulation and control speed and reliable performance.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention.
Fig. 2 is a schematic structural diagram of an oscillation regulation module according to the present invention.
FIG. 3 is a flow chart of the system oscillation control method of the present invention.
Fig. 4 is a graph of the pressure oscillation regulation result of the cryogenic piping system of the present invention in different regulation modes.
FIG. 5 is a graph of pressure oscillations after regulation of a cryolumen tubing system.
In the figure: 1-low temperature liquid storage tank, 2-low temperature pipeline, 3-oscillation regulation module, 4-low temperature liquid, 3.1-expansion regulation element and 3.2-contraction regulation element.
Detailed Description
The present invention will be described in further detail with reference to the following examples, which are not intended to limit the invention thereto.
Referring to fig. 1, the structure for realizing low temperature pipeline system pressure oscillation regulation of the present invention includes a low temperature thermal-acoustic vibration subsystem composed of a low temperature liquid storage tank 1, a low temperature pipeline 2, an oscillation regulation module 3 and a low temperature liquid 4; the low-temperature pipeline 2 is a pipeline with an opening at one end and a closed end, the opening end of the low-temperature pipeline 2 is connected with the low-temperature liquid storage tank 1, and the low-temperature pipeline 2 is provided with an oscillation regulation and control module 3 for regulating the internal pressure of the system; the low-temperature pipeline 2 is positioned in a normal-temperature environment and forms temperature gradient distribution along the axial direction of the pipe together with the opening end of the low-temperature liquid storage tank 1, so that pressure oscillation inside the system is induced.
As shown in fig. 2, the oscillation regulation module 3 of the present invention employs an expansion regulation element 3.1 or a contraction regulation element 3.2; the pipe diameter ratio of the expansion type regulating element 3.1 or the contraction type regulating element 3.2 to the low-temperature pipeline and the relative position of the expansion type regulating element 3.1 or the contraction type regulating element 3.2 to the temperature gradient determine the oscillation state of the regulation and control. When the oscillation regulation and control module 3 is installed at the low-temperature section of the temperature gradient of the low-temperature pipeline 2, the pressure zero oscillation in the low-temperature pipeline system can be realized. The oscillation regulation and control module 3 is arranged at the position of the maximum temperature gradient slope point of the low-temperature pipeline 2, and can realize zero oscillation of pressure in the low-temperature pipeline system when the inner diameter ratio of the expansion regulation and control element 3.1 to the low-temperature pipeline 2 is larger than 1.4. The oscillation regulation and control module 3 is arranged at the position of the maximum temperature gradient slope point of the low-temperature pipeline 2, a contraction type regulation and control element 3.2 is adopted, and zero oscillation of pressure in the low-temperature pipeline system can be realized when the inner diameter ratio of the oscillation regulation and control module to the low-temperature pipeline 2 is less than 0.35. The oscillation regulation and control module 3 is arranged at the temperature gradient high-temperature section of the low-temperature pipeline 2, and can realize zero oscillation of pressure in the low-temperature pipeline system when the inner diameter ratio of the expansion regulation and control element 3.1 to the low-temperature pipeline 2 is less than 1.4. The oscillation regulation and control module 3 is arranged at the temperature gradient high-temperature section of the low-temperature pipeline 2, a contraction regulation and control element 3.2 is adopted, and zero oscillation of pressure in the low-temperature pipeline system can be realized when the inner diameter ratio of the oscillation regulation and control module to the low-temperature pipeline 2 is less than 1.
As shown in fig. 3, the method for regulating and controlling the pressure oscillation of the cryogenic pipeline system according to the present invention includes the following steps:
1) starting the oscillation regulation and control module 3, and measuring and recording the average pressure and pressure oscillation in the low-temperature pipeline 2 system;
2) measuring the high-low temperature ratio, the inner diameter and the temperature gradient of the low-temperature pipeline 2 system;
3) selecting an oscillation regulation module element according to the initial conditions of the cryogenic pipeline system: an expansion regulatory element 3.1 or a contraction regulatory element 3.2;
4) according to the space requirement of the low-temperature pipeline system and the position of the temperature gradient, the position of the expansion regulating element 3.1 or the position of the contraction regulating element 3.2 in the pipeline is determined, and the inner diameter of the expansion regulating element 3.1 or the inner diameter of the contraction regulating element 3.2 are determined.
5) And monitoring and recording pressure oscillation in the low-temperature pipeline to obtain a regulation and control result of the pressure oscillation of the low-temperature pipeline system.
When the oscillation regulation and control module 3 is installed at the low-temperature section of the temperature gradient of the low-temperature pipeline 2, the pressure zero oscillation in the low-temperature pipeline system can be realized. The oscillation regulation and control module 3 is arranged at the position of the maximum temperature gradient slope point of the low-temperature pipeline 2, and can realize zero oscillation of pressure in the low-temperature pipeline system when the inner diameter ratio of the expansion regulation and control element 3.1 to the low-temperature pipeline 2 is larger than 1.4. The oscillation regulation and control module 3 is arranged at the position of the maximum temperature gradient slope point of the low-temperature pipeline 2, a contraction type regulation and control element 3.2 is adopted, and zero oscillation of pressure in the low-temperature pipeline system can be realized when the inner diameter ratio of the oscillation regulation and control module to the low-temperature pipeline 2 is less than 0.35. The oscillation regulation and control module 3 is arranged at the temperature gradient high-temperature section of the low-temperature pipeline 2, and can realize zero oscillation of pressure in the low-temperature pipeline system when the inner diameter ratio of the expansion regulation and control element 3.1 to the low-temperature pipeline 2 is less than 1.4. The oscillation regulation and control module 3 is arranged at the temperature gradient high-temperature section of the low-temperature pipeline 2, a contraction regulation and control element 3.2 is adopted, and zero oscillation of pressure in the low-temperature pipeline system can be realized when the inner diameter ratio of the oscillation regulation and control module to the low-temperature pipeline 2 is less than 1.
The structure and method for realizing the pressure oscillation regulation of the low-temperature pipeline system are further described by the specific embodiment.
Examples
Starting the oscillation regulation and control module 3, and measuring and recording the average pressure and pressure oscillation in the low-temperature pipeline 2 system; with the use of different modes of the regulating element, the regulation result of the pressure oscillation in the cryogenic piping system is shown in fig. 4, in which the position of the dashed line is a stable state of zero oscillation. The high-low temperature ratio of the low-temperature pipeline is 66.7, the inner diameter of the pipeline is 2.85m, the length of the pipeline is 1m, and the temperature gradient is positioned in the middle of the low-temperature pipeline. Selecting different inner diameter ratio (r/r)00.18,0.35,0.53, 0.70,0.88,1.23,1.40,1.75,2.11,2.46,2.81,3.16,3.51), wherein r/r of the expanded regulatory element 3.1 is0>1, r/r of contracting regulatory element 3.20<1, installing the low-temperature pipeline 2 at different positions (x is-0.4 m, -0.3m, -0.2m, -0.1m,0,0.1m,0.2m,0.3m,0.4m), monitoring and recording the pressure oscillation in the pipeline, and obtaining a pressure oscillation chart of the low-temperature pipeline system. FIG. 5a) is a pressure ratio diagram of the position of the control element at different internal diameters when x is 0m, and FIGS. 5b) to e) are respectively the internal diameters in FIG. 5a) (I) r/ro＝0.53，(Ⅱ)r/ro＝0.70，(Ⅲ)r/ro0.88 and (IV) r/ro1.23, where r/roThe regulation achieves a steady state of zero oscillation at 1.23.
The comparison of results of different regulation and control modes shows that the structure for realizing the pressure oscillation regulation and control of the low-temperature pipeline system can effectively inhibit unfavorable pressure oscillation in the low-temperature pipeline system, and has high regulation and control speed and reliable performance.
Claims (3)
1. The utility model provides a realize low temperature pipe-line system pressure oscillation regulation and control's structure which characterized in that: the low-temperature liquid vibration control system comprises a low-temperature liquid storage tank (1) internally provided with low-temperature liquid (4), wherein a low-temperature pipeline (2) with an open end connected with the low-temperature liquid storage tank and a closed other end is arranged in the low-temperature liquid storage tank (1), a pressure vibration control module (3) for adjusting the interior of the system is arranged on the low-temperature pipeline (2), the low-temperature pipeline (2) is positioned in a normal-temperature environment, and the low-temperature pipeline (2) and the open end arranged in the low-temperature liquid storage tank (1) jointly form temperature gradient distribution along the axial direction of a pipe;
the oscillation regulation and control module (3) adopts an expansion regulation and control element (3.1) or a contraction regulation and control element (3.2), the oscillation regulation and control module (3) is installed at a low-temperature section of the temperature gradient of the low-temperature pipeline (2) to realize pressure zero oscillation in the low-temperature pipeline system, the oscillation regulation and control module (3) is installed at the maximum point of the temperature gradient slope of the low-temperature pipeline (2), the inner diameter ratio of the expansion regulation and control element (3.1) and the low-temperature pipeline (2) is more than 1.4 to realize pressure zero oscillation in the low-temperature pipeline system, the oscillation regulation and control module (3) is installed at the maximum point of the temperature gradient slope of the low-temperature pipeline (2), and the inner diameter ratio of the contraction regulation and control element (3.2) and the low-temperature pipeline (2) is less than 0.35 to;
or the oscillation regulation and control module (3) is arranged at the temperature gradient high-temperature section of the low-temperature pipeline (2), the inner diameter ratio of the adopted expansion regulation and control element (3.1) to the low-temperature pipeline (2) is less than 1.4, and the pressure zero oscillation in the low-temperature pipeline system is realized, and the oscillation regulation and control module (3) is arranged at the temperature gradient high-temperature section of the low-temperature pipeline (2), the contraction regulation and control element (3.2) is adopted, and the inner diameter ratio of the adopted expansion regulation and control element to the low-temperature pipeline (2) is less than 1, and the pressure zero oscillation in the.
2. A method for achieving cryogenic piping system pressure oscillation regulation based on the structure of claim 1, comprising the steps of:
1) starting an oscillation regulation and control module (3), and measuring and recording the average pressure and pressure oscillation in the low-temperature pipeline (2) system;
2) measuring the high-low temperature ratio, the inner diameter and the position of the temperature gradient of the low-temperature pipeline (2) system;
3) selecting an oscillation regulation module element according to the initial conditions of the cryogenic pipeline system: an expansion regulatory element (3.1) or a contraction regulatory element (3.2);
4) according to the space requirement of the low-temperature pipeline system and the position of the temperature gradient, the position of the expansion regulating element (3.1) or the contraction regulating element (3.2) in the pipeline is determined, and the inner diameter of the expansion regulating element (3.1) or the contraction regulating element (3.2) is determined.
3. The method of achieving cryogenic piping system pressure oscillation regulation of claim 2, wherein: the oscillation regulation and control module (3) is arranged at a low-temperature section of the temperature gradient of the low-temperature pipeline (2);
the oscillation regulation and control module (3) is arranged at the maximum point of the temperature gradient slope of the low-temperature pipeline (2), and the inner diameter ratio of the adopted expansion regulation and control element (3.1) to the low-temperature pipeline (2) is more than 1.4;
the oscillation regulation and control module (3) is arranged at the maximum point of the temperature gradient slope of the low-temperature pipeline (2), and the inner diameter ratio of the adopted contraction type regulation and control element (3.2) to the low-temperature pipeline (2) is less than 0.35;
or the oscillation regulation and control module (3) is arranged at the temperature gradient high-temperature section of the low-temperature pipeline (2), and the inner diameter ratio of the adopted expansion regulation and control element (3.1) to the low-temperature pipeline (2) is less than 1.4;
the oscillation regulation and control module (3) is arranged at the temperature gradient high-temperature section of the low-temperature pipeline (2), a contraction regulation and control element (3.2) is adopted, and zero oscillation of pressure in the low-temperature pipeline system is realized when the inner diameter ratio of the oscillation regulation and control module to the low-temperature pipeline (2) is less than 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010151716.7A CN111425688B (en) | 2020-03-06 | 2020-03-06 | Structure and method for realizing low-temperature pipeline system pressure oscillation regulation and control |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010151716.7A CN111425688B (en) | 2020-03-06 | 2020-03-06 | Structure and method for realizing low-temperature pipeline system pressure oscillation regulation and control |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111425688A CN111425688A (en) | 2020-07-17 |
| CN111425688B true CN111425688B (en) | 2021-04-27 |
Family
ID=71547438
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010151716.7A Active CN111425688B (en) | 2020-03-06 | 2020-03-06 | Structure and method for realizing low-temperature pipeline system pressure oscillation regulation and control |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111425688B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB281274A (en) * | 1926-11-27 | 1928-12-27 | Sulzer Ag | Improvements in or relating to apparatus for damping shocks and oscillations set up in pipe lines |
| DE2747492A1 (en) * | 1977-10-22 | 1979-04-26 | Messer Griesheim Gmbh | SAFETY INSERT FOR VESSELS FOR STORING LOW-BOILING LIQUID GASES |
| CN107917337A (en) * | 2017-11-14 | 2018-04-17 | 上海交通大学 | Liquid helium vessel thermal acoustic oscillation restraining device based on capacity damping air reservoir |
| CN110017707A (en) * | 2017-12-08 | 2019-07-16 | 和承R&A有限公司 | The dual pipe in pipe of noise reducing type |
-
2020
- 2020-03-06 CN CN202010151716.7A patent/CN111425688B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB281274A (en) * | 1926-11-27 | 1928-12-27 | Sulzer Ag | Improvements in or relating to apparatus for damping shocks and oscillations set up in pipe lines |
| DE2747492A1 (en) * | 1977-10-22 | 1979-04-26 | Messer Griesheim Gmbh | SAFETY INSERT FOR VESSELS FOR STORING LOW-BOILING LIQUID GASES |
| CN107917337A (en) * | 2017-11-14 | 2018-04-17 | 上海交通大学 | Liquid helium vessel thermal acoustic oscillation restraining device based on capacity damping air reservoir |
| CN110017707A (en) * | 2017-12-08 | 2019-07-16 | 和承R&A有限公司 | The dual pipe in pipe of noise reducing type |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111425688A (en) | 2020-07-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112415051B (en) | High-temperature heat pipe heat transfer performance and failure test experimental device | |
| CN111425688B (en) | Structure and method for realizing low-temperature pipeline system pressure oscillation regulation and control | |
| CN112595485A (en) | Ultra-high temperature pipe wind tunnel driving system and use method thereof | |
| CN219103804U (en) | Heat exchange pipeline of high-pressure liquid hydrogen vaporizer | |
| CN213874888U (en) | Ultra-high temperature tube wind tunnel driving system | |
| CN210426945U (en) | Heat-preservation flexible hose for hypersonic wind tunnel heat jet flow interference test | |
| CN203337469U (en) | Cryostat for cryogenic pressure pipeline test | |
| CN112487644A (en) | Research platform and method for flow heat transfer and automatic control | |
| CN103470918A (en) | Compensator-less vacuum pipe for transferring low-temperature fluid | |
| CN114441586B (en) | Experimental device capable of accurately measuring high-pressure volume change rate of phase-change material | |
| CN112145811A (en) | Be applied to elastic support subassembly of LNG double-walled pipe | |
| CN210345021U (en) | Self-circulation type LNG pipeline precooling system | |
| CN209944796U (en) | Thermal capacitance and thermal resistance double-effect coupled deep low-temperature high-precision temperature control device | |
| CN107894211B (en) | Pipeline inner diameter change detection device and detection method | |
| CN220416997U (en) | Medium-sized volume vertical deep-cold pressure container supporting structure | |
| CN217815365U (en) | Prefabricated direct-burried insulating tube positioner | |
| CN110595722A (en) | Heat-preservation flexible hose for hypersonic wind tunnel heat jet flow interference test | |
| CN219013582U (en) | Stainless steel pipe for condenser | |
| CN221196526U (en) | Sectional compensation fixing mechanism for steam pipeline | |
| CN220958665U (en) | A compensation exhaust sluicing device for heating system in monomer building | |
| CN213871668U (en) | Large pull rod corrugated pipe compensator provided with measuring device | |
| CN221612362U (en) | Auxiliary device for mobile temperature control mechanical seal test | |
| CN219300145U (en) | Connecting device for polyurethane spraying polyethylene winding heat-insulating pipe | |
| Zhang et al. | A loop thermoacoustic refrigeration system using flexible resonance tubes. Part I: Inner diameter variation and simulation analysis | |
| CN116066641B (en) | Petroleum pipeline coupling with sealing structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |