CN114905230A - Inner finned tube and processing method thereof - Google Patents
Inner finned tube and processing method thereof Download PDFInfo
- Publication number
- CN114905230A CN114905230A CN202210469654.3A CN202210469654A CN114905230A CN 114905230 A CN114905230 A CN 114905230A CN 202210469654 A CN202210469654 A CN 202210469654A CN 114905230 A CN114905230 A CN 114905230A
- Authority
- CN
- China
- Prior art keywords
- tube
- finned tube
- pipe body
- flanges
- processing method
- 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.)
- Granted
Links
- 238000003672 processing method Methods 0.000 title claims abstract description 12
- 238000003466 welding Methods 0.000 claims abstract description 16
- 238000005096 rolling process Methods 0.000 claims abstract description 7
- 238000003801 milling Methods 0.000 claims abstract description 5
- 238000000034 method Methods 0.000 claims abstract description 4
- 238000010438 heat treatment Methods 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 4
- 238000007493 shaping process Methods 0.000 claims description 4
- 238000000137 annealing Methods 0.000 claims description 3
- 238000003754 machining Methods 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims 1
- 239000000463 material Substances 0.000 abstract description 7
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000004408 titanium dioxide Substances 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000007373 indentation Methods 0.000 description 1
- -1 iron ion Chemical class 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/26—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass heat exchangers or the like
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F1/00—Tubular elements; Assemblies of tubular elements
- F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
- F28F1/40—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only inside the tubular element
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P2700/00—Indexing scheme relating to the articles being treated, e.g. manufactured, repaired, assembled, connected or other operations covered in the subgroups
- B23P2700/09—Heat pipes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Geometry (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention relates to an inner finned tube for heat exchange, in particular to an inner finned tube and a processing method thereof. The processing method comprises the following steps: preparing two rectangular flat plates, rolling the two rectangular flat plates into semi-circular end faces respectively through a press, milling sawteeth on the inner surfaces of the two rolled semi-circular end faces respectively, welding longitudinal seams of the two semi-circular end faces after the sawteeth are milled to form a pipe body, and welding flanges at two ends of the pipe body respectively. The inner finned tube is formed by welding two semicircular parts, no material is accumulated in the inner finned tube, the temperature difference is small, and the material purity is high. The processing method of the invention has simple operation, good processing quality and no deformation of the finned tube in the processing process.
Description
Technical Field
The invention relates to an inner finned tube for heat exchange, in particular to an inner finned tube and a processing method thereof.
Background
The function of the inner finned tube is to rapidly reduce the temperature of the titanium dioxide passing through the inner finned tube from 1000 ℃ to 600 ℃. Only a single inner finned tube with the length of 3 meters exists in the existing industry, and during machining, an inner tooth is planed on a rectangular flat plate with the length of 3 meters, then the flat plate is rolled and formed, longitudinal seams are welded, and finally flanges are welded at two ends. The formed inner finned tube is low in sawtooth precision and easy to scrape; because the titanium dioxide inside is cooled unevenly because the diameter is big, and the difference in temperature between the feed end and the discharge end is too big because of the short length, and the material purity is not high.
In addition, if the length of the inner finned tube is to be increased, the inner finned tube with the length of 6 meters can be welded only by using two inner finned tubes with the length of 3 meters, and the two inner finned tubes with the length of 3 meters are welded in a girth mode, so that materials are accumulated at the girth joint; moreover, two inner finned tubes with the length of 3 meters are welded, so that the straightness is low and the heat exchange effect is poor.
Disclosure of Invention
In order to solve the problems of the existing inner finned tube, the invention aims to provide an inner finned tube with a single length of up to 6 meters and a processing method thereof.
The purpose of the invention is realized by the following technical scheme:
the inner finned tube comprises a tube body and flanges, wherein the tube body of the inner finned tube is divided into two identical parts, the end face of each part is semicircular, the two parts are longitudinally welded into the inner finned tube, the flanges are welded at the two ends of the tube body, and a plurality of toothed fins are uniformly distributed on the inner surface of the tube body in the circumferential direction.
Wherein: the end faces of the two ends of the pipe body are coplanar with the outer end faces of the flanges at the two ends respectively.
The length of the fin is equal to that of the tube body.
The inside of one end of body is the undergauge structure.
The pipe body is provided with two symmetrical welding seams only along the longitudinal direction.
The processing method of the inner finned tube comprises the following steps:
step A, preparing two rectangular flat plates;
step B, rolling the two rectangular flat plates into semi-circular end surfaces through a press machine respectively;
step C, respectively milling saw teeth on the inner surfaces of the two rolled semi-circles;
d, welding longitudinal seams of the two semicircular closed openings after the sawteeth are milled to form the pipe body;
and E, respectively welding flanges at two ends of the pipe body.
Wherein: and in the step B, the two rectangular flat plates are respectively subjected to cold pressing by a press machine, shaped and formed, and are subjected to annealing heat treatment in an electric furnace before the last shaping, and then discharged from the furnace for air cooling.
In the step B, machining allowance is reserved on the single side of the inner circle, the single side of the outer circle and two ends in the length direction of each semi-circle after the rolling forming.
And in the step B, an outer groove is processed in one end of the pipe body to form a reducing structure.
The invention has the advantages and positive effects that:
1. the inner finned tube is formed by welding two semicircular parts, no material is accumulated in the inner finned tube, the temperature difference is small, and the material purity is high.
2. The processing method of the invention has simple operation, good processing quality and no deformation of the finned tube in the processing process.
Drawings
FIG. 1 is a cross-sectional view showing the internal structure of an inner finned tube according to the present invention;
FIG. 2 is a right side view of FIG. 1;
FIG. 3 is a cross-sectional view taken along line A-A of FIG. 1;
FIG. 4 is a schematic perspective view of a half-tube body of the inner fin tube of the present invention;
wherein: 1 is a tube body, 2 is a flange, and 3 is a fin.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
As shown in fig. 1 to 4, the inner finned tube of the invention comprises a tube body 1 and a flange 2, wherein the tube body 1 of the inner finned tube is divided into two identical parts, the end surface of each part is semicircular, the two parts are longitudinally welded into the inner finned tube, the flanges 2 are welded at the two ends of the tube body 1, and a plurality of tooth-shaped fins 3 are uniformly distributed on the inner surface of the tube body 1 along the circumferential direction.
The pipe body 1 of the embodiment is formed by welding two semicircular parts, and only two symmetrical welding seams are formed along the longitudinal direction (namely the axial direction of the pipe body 1), so that the problem of material accumulation at the annular welding seam after the existing inner finned pipe is welded by two circular pipes is solved.
In this embodiment, the end surfaces of the two ends of the tube body 1 are coplanar with the outer end surfaces of the flanges 2 at the two ends, respectively, and the length of the fins 3 inside the tube body 1 is equal to the length of the tube body 1. The inner part of one end of the pipe body 1 is of a reducing structure.
The processing method of the inner finned tube comprises the following steps:
step A, preparing two rectangular flat plates, wherein the flat plates can be made of stainless steel and have the brand number of N02200.
And step B, rolling the two rectangular flat plates into semi-circular end faces through a press machine respectively.
Cold pressing the rectangular flat plate by a 7000-ton press, shaping, feeding the rectangular flat plate into an electric furnace for annealing heat treatment before the last shaping, wherein the heating temperature is 780 ℃ plus or minus 20 ℃, the heat preservation time is 1.7-2 hours, the heating rate is 55-130 ℃/h, the cooling rate is 55-166 ℃/h, and when the temperature is reduced to below 300 ℃, discharging and air cooling. Before being heated in an electric furnace, the furnace needs to be degreased and cleaned, and the surface oil stain, lubricant and other harmful impurities are removed. The shape and size of the plate must accord with the inner and outer arc templates, and the plate surface is protected by paying attention to the fact that indentation, collision, scratch and iron ion pollution are forbidden.
And (3) reserving 3mm allowance on one side of the inner circle of each semi-circular blank after rolling forming, reserving 1mm allowance on one side of the outer circle, respectively reserving 13.5mm allowances at two ends in the length direction, and requiring that the maximum and minimum diameter difference is less than or equal to 3mm and the total straightness is less than or equal to 3 mm. The blank surface can not have the defects of oil stain, flash and burr, collision and scratch and the like, and the peripheral sharp corners are polished smoothly.
An outer groove is formed within a set range (300 mm from the end of the pipe body 1 in this embodiment) from the end of the pipe body 1, and a diameter-reduced structure is formed.
And buckling the two semicircular blanks together, checking the conditions of shape coincidence and misalignment, finding out the combination with the best matching degree, and performing pairing marking on every two blanks.
The outer surface connected with the flange is processed respectively at the two ends of the pipe body 1, the width of the outer surface is larger than the thickness of the flange, and the positions which are increased are chamfered (the embodiment can be 60 degrees) to ensure smooth transition with the unmachined surface.
And C, respectively milling saw teeth on the inner surfaces of the two rolled semi-circular surfaces, and removing burrs, iron scraps and oil stains after finishing milling.
D, welding longitudinal seams of the two semicircular closed openings after the sawteeth are milled to form a pipe body 1; the part of the internal reducing structure at one end of the tube body 1 is welded by hand, and the rest part adopts plasma welding.
And E, respectively welding flanges 2 at two ends of the pipe body 1, processing end faces of the flanges 2 at the two ends, and processing bolt holes to ensure that the two end faces of the inner finned pipe are parallel.
Claims (9)
1. An inner finned tube, characterized in that: the novel finned tube comprises a tube body (1) and flanges (2), wherein the tube body (1) of the inner finned tube is divided into two identical parts, the end face of each part is semicircular, the two parts are welded into the inner finned tube along the longitudinal direction, the flanges (2) are welded at the two ends of the tube body (1), and a plurality of toothed fins (3) are uniformly distributed on the inner surface of the tube body (1) along the circumferential direction.
2. The inner fin tube according to claim 1, wherein: the end faces of the two ends of the pipe body (1) are coplanar with the outer end faces of the flanges (2) at the two ends respectively.
3. The inner fin tube according to claim 1, wherein: the length of the fin (3) is equal to that of the tube body (1).
4. The inner fin tube according to claim 1, wherein: the inside of one end of body (1) is the undergauge structure.
5. The inner fin tube according to claim 1, wherein: the pipe body (1) is only provided with two symmetrical welding seams along the longitudinal direction.
6. A method for manufacturing an internally finned tube as claimed in any one of claims 1 to 5, characterized in that: comprises the following steps
Step A, preparing two rectangular flat plates;
step B, rolling the two rectangular flat plates into semi-circular end surfaces through a press machine respectively;
step C, respectively milling saw teeth on the inner surfaces of the two rolled semi-circles;
d, welding longitudinal seams of the two semicircular closed openings after the sawteeth are milled to form the pipe body (1);
and E, respectively welding flanges (2) at two ends of the pipe body (1).
7. The processing method according to claim 6, characterized in that: and in the step B, the two rectangular flat plates are respectively subjected to cold pressing by a press machine, shaped and formed, and are subjected to annealing heat treatment in an electric furnace before the last shaping, and then discharged from the furnace for air cooling.
8. The processing method according to claim 6, characterized in that: in the step B, machining allowance is reserved on the single side of the inner circle, the single side of the outer circle and two ends in the length direction of each semi-circle after the rolling forming.
9. The process of claim 6, wherein: and in the step B, an outer groove is processed in one end of the pipe body (1) to form a reducing structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210469654.3A CN114905230B (en) | 2022-04-28 | 2022-04-28 | Inner finned tube and processing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210469654.3A CN114905230B (en) | 2022-04-28 | 2022-04-28 | Inner finned tube and processing method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114905230A true CN114905230A (en) | 2022-08-16 |
| CN114905230B CN114905230B (en) | 2024-08-06 |
Family
ID=82764610
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210469654.3A Active CN114905230B (en) | 2022-04-28 | 2022-04-28 | Inner finned tube and processing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114905230B (en) |
Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4163474A (en) * | 1976-03-10 | 1979-08-07 | E. I. Du Pont De Nemours And Company | Internally finned tube |
| US4856165A (en) * | 1987-10-01 | 1989-08-15 | Man Technologie Gmbh | Method for producing by welding a finned heat exchanger pipe |
| CN1062110A (en) * | 1990-12-08 | 1992-06-24 | Gea气体冷却器有限公司 | Make the method and the equipment thereof of heat exchanger |
| CN1097366A (en) * | 1993-04-23 | 1995-01-18 | 巴尔克德股份公司 | Produce the method and apparatus of heat exchange elements and attached band finned tube thereof |
| JPH11254033A (en) * | 1998-03-09 | 1999-09-21 | Nisshin Steel Co Ltd | Manufacture of metal tube with its inside partitioned with partition wall along longitudinal direction |
| CN1981975A (en) * | 2005-12-15 | 2007-06-20 | 株式会社电装 | Method of manufacturing heat exchanger tube and heat exchanger |
| WO2009073638A1 (en) * | 2007-11-30 | 2009-06-11 | Holtec International, Inc. | Fin tube assembly for air cooled heat exchanger and method of manufacturing the same |
| CN203177708U (en) * | 2013-01-22 | 2013-09-04 | 昌图县八面城镇百道尔热风炉厂 | Finned tube for hot blast furnace |
| CN103292629A (en) * | 2012-03-01 | 2013-09-11 | 欧司朗股份有限公司 | Heat pipe and manufacturing method thereof |
| CN203203453U (en) * | 2013-01-06 | 2013-09-18 | 北京龙源冷却技术有限公司 | Flat tube type finned tube |
| CN204666012U (en) * | 2015-04-21 | 2015-09-23 | 无锡华瑞铝业有限公司 | A kind of combined type concurrent flow spray zinc hollow aluminum flat tube configuration |
| CN204988008U (en) * | 2015-07-30 | 2016-01-20 | 王金淼 | Thick gaseous medium heat transfer device is glued to tubular non - |
| CN105444602A (en) * | 2015-12-04 | 2016-03-30 | 安阳方快锅炉有限公司 | Novel inner finned pipe for boiler |
| CN106767096A (en) * | 2016-12-29 | 2017-05-31 | 浙江久立特材科技股份有限公司 | A kind of corrosion resistant alloy finned tube and manufacture method |
| CN208223269U (en) * | 2018-05-25 | 2018-12-11 | 方快锅炉有限公司 | A kind of boiler inner fin heat exchange tube |
-
2022
- 2022-04-28 CN CN202210469654.3A patent/CN114905230B/en active Active
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4163474A (en) * | 1976-03-10 | 1979-08-07 | E. I. Du Pont De Nemours And Company | Internally finned tube |
| US4856165A (en) * | 1987-10-01 | 1989-08-15 | Man Technologie Gmbh | Method for producing by welding a finned heat exchanger pipe |
| CN1062110A (en) * | 1990-12-08 | 1992-06-24 | Gea气体冷却器有限公司 | Make the method and the equipment thereof of heat exchanger |
| CN1097366A (en) * | 1993-04-23 | 1995-01-18 | 巴尔克德股份公司 | Produce the method and apparatus of heat exchange elements and attached band finned tube thereof |
| JPH11254033A (en) * | 1998-03-09 | 1999-09-21 | Nisshin Steel Co Ltd | Manufacture of metal tube with its inside partitioned with partition wall along longitudinal direction |
| CN1981975A (en) * | 2005-12-15 | 2007-06-20 | 株式会社电装 | Method of manufacturing heat exchanger tube and heat exchanger |
| WO2009073638A1 (en) * | 2007-11-30 | 2009-06-11 | Holtec International, Inc. | Fin tube assembly for air cooled heat exchanger and method of manufacturing the same |
| CN103292629A (en) * | 2012-03-01 | 2013-09-11 | 欧司朗股份有限公司 | Heat pipe and manufacturing method thereof |
| CN203203453U (en) * | 2013-01-06 | 2013-09-18 | 北京龙源冷却技术有限公司 | Flat tube type finned tube |
| CN203177708U (en) * | 2013-01-22 | 2013-09-04 | 昌图县八面城镇百道尔热风炉厂 | Finned tube for hot blast furnace |
| CN204666012U (en) * | 2015-04-21 | 2015-09-23 | 无锡华瑞铝业有限公司 | A kind of combined type concurrent flow spray zinc hollow aluminum flat tube configuration |
| CN204988008U (en) * | 2015-07-30 | 2016-01-20 | 王金淼 | Thick gaseous medium heat transfer device is glued to tubular non - |
| CN105444602A (en) * | 2015-12-04 | 2016-03-30 | 安阳方快锅炉有限公司 | Novel inner finned pipe for boiler |
| CN106767096A (en) * | 2016-12-29 | 2017-05-31 | 浙江久立特材科技股份有限公司 | A kind of corrosion resistant alloy finned tube and manufacture method |
| CN208223269U (en) * | 2018-05-25 | 2018-12-11 | 方快锅炉有限公司 | A kind of boiler inner fin heat exchange tube |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114905230B (en) | 2024-08-06 |
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