CN106949776A - PTFE tube ends fixed structure and method in a kind of heat exchanger - Google Patents
PTFE tube ends fixed structure and method in a kind of heat exchanger Download PDFInfo
- Publication number
- CN106949776A CN106949776A CN201710292554.7A CN201710292554A CN106949776A CN 106949776 A CN106949776 A CN 106949776A CN 201710292554 A CN201710292554 A CN 201710292554A CN 106949776 A CN106949776 A CN 106949776A
- Authority
- CN
- China
- Prior art keywords
- inner sleeve
- heat exchanger
- ptfe
- connection inner
- metal card
- 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.)
- Pending
Links
- 239000004810 polytetrafluoroethylene Substances 0.000 title claims abstract description 75
- 229920001343 polytetrafluoroethylene Polymers 0.000 title claims abstract description 75
- 238000000034 method Methods 0.000 title abstract description 6
- 229910052751 metal Inorganic materials 0.000 claims abstract description 41
- 239000002184 metal Substances 0.000 claims abstract description 41
- 239000000463 material Substances 0.000 claims abstract description 20
- 239000012943 hotmelt Substances 0.000 claims abstract description 11
- 238000007789 sealing Methods 0.000 claims description 10
- 238000005260 corrosion Methods 0.000 claims description 9
- 230000007797 corrosion Effects 0.000 claims description 4
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 2
- 239000010931 gold Substances 0.000 claims description 2
- 229910052737 gold Inorganic materials 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 230000007306 turnover Effects 0.000 claims 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000003546 flue gas Substances 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 239000000779 smoke Substances 0.000 description 2
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 229920000840 ethylene tetrafluoroethylene copolymer Polymers 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 150000007530 organic bases Chemical class 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- -1 polytetrafluoroethylene Polymers 0.000 description 1
- 230000002940 repellent Effects 0.000 description 1
- 239000005871 repellent Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/02—Header boxes; End plates
- F28F9/04—Arrangements for sealing elements into header boxes or end plates
- F28F9/16—Arrangements for sealing elements into header boxes or end plates by permanent joints, e.g. by rolling
- F28F9/162—Arrangements for sealing elements into header boxes or end plates by permanent joints, e.g. by rolling by using bonding or sealing substances, e.g. adhesives
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F21/00—Constructions of heat-exchange apparatus characterised by the selection of particular materials
- F28F21/06—Constructions of heat-exchange apparatus characterised by the selection of particular materials of plastics material
- F28F21/062—Constructions of heat-exchange apparatus characterised by the selection of particular materials of plastics material the heat-exchange apparatus employing tubular conduits
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention discloses PTFE tube ends fixed structure and method in a kind of heat exchanger, including metal card and PTFE heat exchanger tubes, metal card is provided with several mounting holes, PTFE heat exchanger tubes are in mounting hole, the connection inner sleeve of a PTFE material is equipped with described each mounting hole, PTFE tube ends are located in connection inner sleeve and are connected to a fixed with being connected inner sleeve by hot melt, connection inner sleeve upper end is provided with external screw thread and passes mounting hole, lower end also passes mounting hole and sets L-shaped flange, connection inner sleeve upper end is additionally provided with a clamp nut, metal card on connection inner sleeve upper end and is pressed abd fixed between clamp nut and L-shaped flange by clamp nut by screwed.The present invention can realize effective connection of the PTFE heat exchanger tubes in heat exchanger.
Description
Technical field
It is solid more specifically to PTFE tube ends in a kind of heat exchanger the present invention relates to PTFE heat exchanger technologies
Fixed structure and method.
Background technology
PTFE (polytetrafluoroethylene (PTFE)) tubing has excellent high-low temperature resistant characteristic, can be grown under conditions of -190~260 DEG C
Phase uses.PTFE material has good chemical stability, and only performance can change under fluorine steam, alkali metal under high temperature, right
Other all dense, dilute inorganic Organic Acid and Bases, ester do not react.Low surface friction coefficient, water repellent is refused inside and outside dirt, tube wall
Not incrustation.It is nontoxic, the features such as nonflammable, with the high grade of transparency, it is widely used in fluoroplastics heat exchanger, heat steam pipe arrangement etc.
Field, tool has been widely used.
Therefore the heat exchanger run under the stronger environment of corrosivity, its inside is general to be all made of PTFE heat exchanger tubes, so
And, as high performance plastics, PTFE material can not melting extrusion, because the property of material also is difficult to other materials (such as
Metal material) mutually splicing or very high intensity is kept during slitless connection.At present, metal in PTFE heat exchanger tubes and heat exchanger is spent
The connected mode commonly used between plate is as shown in figure 1, there is provided a few road grooves 3, are incited somebody to action on the inwall of mounting hole 2 of metal card 1
After PTFE heat exchanger tubes 4 are put into mounting hole 2, by the way of being expanded in PTFE heat exchanger tubes 4, by the tube wall of PTFE heat exchanger tubes 4
Outwardly against to being attached in groove 3, because metal card 1 and PTFE heat exchanger tubes 4 are two kinds of unlike materials, there is heat expansion
During shrinkage phenomenon, its internal particle (atom) motion is different, therefore the amplitude expanded with heat and contract with cold of two kinds of materials is also different, therefore
After phenomenon of expanding with heat and contract with cold is repeated multiple times, makes easily to come off between metal card 1 and PTFE heat exchanger tubes 4, cause heat exchanger failure, no
It can for a long time be operated, need to periodically be safeguarded.
The content of the invention
For drawbacks described above present in prior art, it is an object of the invention to provide PTFE heat exchanger tubes in a kind of heat exchanger
End fixed structure and method, can realize effective connection of the PTFE heat exchanger tubes in heat exchanger.
To achieve the above object, the present invention is adopted the following technical scheme that：
On the one hand, PTFE tube end fixed structures in a kind of heat exchanger, including metal card and PTFE heat exchanger tubes, gold
Belong to card and be provided with several mounting holes, PTFE heat exchanger tubes are equipped with a PTFE in mounting hole in described each mounting hole
The connection inner sleeve of material, PTFE tube ends are located in connection inner sleeve and are connected with being connected inner sleeve by hot melt
Fixed, connection inner sleeve upper end is provided with external screw thread and passes mounting hole, and lower end also passes mounting hole and sets L-shaped flange, even
Connect inner sleeve upper end and be additionally provided with a clamp nut, clamp nut on connection inner sleeve upper end and is spent metal by screwed
Plate is pressed abd fixed between clamp nut and L-shaped flange.
Anti-corrosion layer is also covered with described metal card inner surface.
Described anti-corrosion layer is PTFE film.
Described fastening bolt is PTFE material.
Hot melt wlding is additionally provided between described connection inner sleeve and PTFE heat exchanger tubes.
Sealing ring is equipped between described clamp nut and metal card, between metal card and L-shaped flange.
On the other hand, PTFE tube end fixing means in a kind of heat exchanger, each mounting hole on metal card
The connection inner sleeve of a PTFE material is inside respectively mounted, connection inner sleeve upper end passes mounting hole, and on provided with connection inner sleeve
End sets external screw thread, and connection inner sleeve lower end also passes mounting hole and sets L-shaped flange, PTFE tube ends are located in
It is connected to a fixed, then is screwed on the external screw thread of connection inner sleeve upper end by hot melt in connection inner sleeve and with being connected inner sleeve
Metal card, is pressed abd fixed between clamp nut and L-shaped flange by one clamp nut by tightening clamp nut, in fastening spiral shell
A sealing ring is placed between female and metal card, between metal card and L-shaped flange.
In above-mentioned technical scheme, in a kind of heat exchanger provided by the present invention PTFE tube ends fixed structure and
Method, makes the connection between metal card and PTFE heat exchanger tubes more firm, stable and reliable.It can be efficiently applied to for example high
Being tightly connected between temperature, the PTFE heat exchanger tubes of heat exchanger under high corrosion operating mode and metal card, be not only able to it is cost-effective,
But also sealing intensity is greatly improved, extend the service life of equipment.
Brief description of the drawings
Fig. 1 is a kind of structural representation of connected mode of prior art；
Fig. 2 is the structural representation of the present invention；
Fig. 3 is the structural representation that placed hot melt wlding in the present invention between connection inner sleeve and PTFE heat exchanger tubes.
Embodiment
Technical scheme is further illustrated with reference to the accompanying drawings and examples.
Incorporated by reference to shown in Fig. 2 and Fig. 3, PTFE tube end fixed structures in a kind of heat exchanger provided by the present invention,
Including metal card 10 and PTFE heat exchanger tubes 11, metal card is provided with several mounting holes, and PTFE heat exchanger tubes 11 are located at mounting hole
Interior, above-mentioned is prior art part, is just repeated no more herein.Unlike the prior art, in described each mounting hole
Connection inner sleeve 12 provided with a PTFE material, the end of PTFE heat exchanger tubes 11 is located in connection inner sleeve 12, and PTFE material is not
But with etch-proof characteristic so that connection inner sleeve 12 is identical with the material of PTFE heat exchanger tubes 11, also allow for connecting inner sleeve
It is connected to a fixed between 12 and PTFE heat exchanger tubes 11 by hot melt, heat fusion joint is typically at 325 DEG C ± 10 DEG C, on connection inner sleeve 12
End is provided with external screw thread and passes mounting hole, and lower end also passes mounting hole and sets L-shaped flange 121, connection inner sleeve 12 upper end
A clamp nut 13 is additionally provided with, clamp nut 13 behind connection inner sleeve 12 upper end and is pressed metal card 10 by screwed
Fasten between clamp nut 13 and L-shaped flange 121, and between clamp nut 13 and metal card 10 and metal flower
Sealing ring 14 is equipped between plate 10 and L-shaped flange 121, when the end of PTFE heat exchanger tubes 11 is fixed on connection inner sleeve 12
After interior so that all in a kind of sealing structure state inside heat exchanger, it is prevented from the smoke spillage inside heat exchanger and extremely exchanges heat
The outside of device.
Preferably, being also covered with anti-corrosion layer 101 on the described inner surface of metal card 10, anti-corrosion layer 101 is PTFE
Film, prevents the metal material of metal card 10 by the flue gas corrosion inside heat exchanger, so as to extend the service life of equipment.
Preferably, described fastening bolt 13 is PTFE material, it is between clamp nut 13 and connection inner sleeve 12 upper end
Threaded connection, after fastening bolt 13 is tightened, is on the one hand prevented from connection inner sleeve 12 and is slid out of mounting hole, on the other hand
The L-shaped flange 121 of the lower end of connection inner sleeve 12 can also be made to be close to the surface of metal card 10, so as to compress two sealings again
Circle 14, forms a sealing structure, the smoke spillage inside heat exchanger is prevented to the outside of heat exchanger, from PTFE material
Fastening bolt 13 can further prevent fastening bolt 13 by flue gas corrosion.
Preferably, being additionally provided with hot melt wlding 5 between described connection inner sleeve 12 and PTFE heat exchanger tubes 10, wlding 5 is heated
For FEP, PFA or ETFE, first hot melt wlding 5 is put into connection inner sleeve 12, then the end of PTFE heat exchanger tubes 10 is put into heat
In melting welding material 5, PTFE heat exchanger tubes 10 are fastened in connection inner sleeve 12 by heating wlding 5, the heat fusion joint one of which
As at 265 DEG C ± 10 DEG C.
PTFE tube end fixing means in a kind of heat exchanger provided by the present invention, each peace on metal card
The connection inner sleeve of a PTFE material is respectively mounted in dress hole, connection inner sleeve upper end passes mounting hole, and provided with connection inner sleeve
Pipe upper end sets external screw thread, and connection inner sleeve lower end also passes mounting hole and sets L-shaped flange, PTFE tube ends are worn
It is located in connection inner sleeve and is connected to a fixed with being connected inner sleeve by hot melt, then on the external screw thread of connection inner sleeve upper end
A clamp nut is screwed into, metal card is pressed abd fixed between clamp nut and L-shaped flange by tightening clamp nut, tight
Gu place a sealing ring between nut and metal card, between metal card and L-shaped flange.
In summary, the present invention to connected mode between PTFE heat exchanger tubes and metal card by being improved so that
The connection of PTFE heat exchanger tubes and metal card is more firm, while having anticorrosion, the function of anti-leak again, it is adaptable to Suo Youhuan
The use of hot device.
Those of ordinary skill in the art it should be appreciated that the embodiment of the above be intended merely to explanation the present invention,
And be not used as limitation of the invention, as long as in the spirit of the present invention, the change to embodiment described above
Change, modification will all fall in the range of claims of the present invention.
Claims (7)
1. on PTFE tube ends fixed structure in a kind of heat exchanger, including metal card and PTFE heat exchanger tubes, metal card
Provided with several mounting holes, PTFE heat exchanger tubes are in mounting hole, it is characterised in that be equipped with one in described each mounting hole
The connection inner sleeve of PTFE material, PTFE tube ends are located in connection inner sleeve and with being connected inner sleeve by heating phase
It is connected, connection inner sleeve upper end is provided with external screw thread and passes mounting hole, and lower end also passes mounting hole and sets L-shaped turn over
Side, connection inner sleeve upper end is additionally provided with a clamp nut, and clamp nut is by the way that screwed is on connection inner sleeve upper end and incites somebody to action
Metal card is pressed abd fixed between clamp nut and L-shaped flange.
2. PTFE tube end fixed structures in a kind of heat exchanger as claimed in claim 1, it is characterised in that described gold
Anti-corrosion layer is also covered with category card inner surface.
3. PTFE tube end fixed structures in a kind of heat exchanger as claimed in claim 2, it is characterised in that described is resistance to
Corrosion layer is PTFE film.
4. PTFE tube end fixed structures in a kind of heat exchanger as claimed in claim 1, it is characterised in that described is tight
Fixing bolt is PTFE material.
5. PTFE tube end fixed structures in a kind of heat exchanger as claimed in claim 1, it is characterised in that described company
Connect and hot melt wlding is additionally provided between inner sleeve and PTFE heat exchanger tubes.
6. PTFE tube end fixed structures in a kind of heat exchanger as claimed in claim 1, it is characterised in that described is tight
Gu it is equipped with sealing ring between nut and metal card, between metal card and L-shaped flange.
7. a kind of PTFE tube ends fixing means in heat exchanger, it is characterised in that each mounting hole on metal card
The connection inner sleeve of a PTFE material is inside respectively mounted, connection inner sleeve upper end passes mounting hole, and on provided with connection inner sleeve
End sets external screw thread, and connection inner sleeve lower end also passes mounting hole and sets L-shaped flange, PTFE tube ends are located in
It is connected to a fixed, then is screwed on the external screw thread of connection inner sleeve upper end by hot melt in connection inner sleeve and with being connected inner sleeve
Metal card, is pressed abd fixed between clamp nut and L-shaped flange by one clamp nut by tightening clamp nut, in fastening spiral shell
A sealing ring is placed between female and metal card, between metal card and L-shaped flange.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710292554.7A CN106949776A (en) | 2017-04-28 | 2017-04-28 | PTFE tube ends fixed structure and method in a kind of heat exchanger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710292554.7A CN106949776A (en) | 2017-04-28 | 2017-04-28 | PTFE tube ends fixed structure and method in a kind of heat exchanger |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106949776A true CN106949776A (en) | 2017-07-14 |
Family
ID=59477034
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710292554.7A Pending CN106949776A (en) | 2017-04-28 | 2017-04-28 | PTFE tube ends fixed structure and method in a kind of heat exchanger |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106949776A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108889130A (en) * | 2018-06-26 | 2018-11-27 | 湖州科滤膜技术有限公司 | A kind of membrane separation plant that security performance is high connection protection pipe |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4834930A (en) * | 1986-04-28 | 1989-05-30 | Akzo N.V. | Method for the manufacture of apparatus for the transfer of heat and/or mass |
| CN202582331U (en) * | 2012-04-18 | 2012-12-05 | 南京斯迈柯特种金属装备股份有限公司 | Corrosion-resistant titanium U-shaped pipe heat exchanger pipe plate structure |
| CN203298648U (en) * | 2013-05-15 | 2013-11-20 | 中石化洛阳工程有限公司 | Polytetrafluoroethylene tube type air preheater |
| CN204630446U (en) * | 2015-03-11 | 2015-09-09 | 北京中电科荟热力技术有限公司 | A kind of mounting structure of flue gas heat-exchange unit |
| CN204963654U (en) * | 2015-07-22 | 2016-01-13 | 沃斯坦热力设备（天津）有限公司 | A tube sheet assembly structure for hydrophily jie's fluoroplastics gas gas heater |
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-
2017
- 2017-04-28 CN CN201710292554.7A patent/CN106949776A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4834930A (en) * | 1986-04-28 | 1989-05-30 | Akzo N.V. | Method for the manufacture of apparatus for the transfer of heat and/or mass |
| CN202582331U (en) * | 2012-04-18 | 2012-12-05 | 南京斯迈柯特种金属装备股份有限公司 | Corrosion-resistant titanium U-shaped pipe heat exchanger pipe plate structure |
| CN203298648U (en) * | 2013-05-15 | 2013-11-20 | 中石化洛阳工程有限公司 | Polytetrafluoroethylene tube type air preheater |
| CN204630446U (en) * | 2015-03-11 | 2015-09-09 | 北京中电科荟热力技术有限公司 | A kind of mounting structure of flue gas heat-exchange unit |
| CN204963654U (en) * | 2015-07-22 | 2016-01-13 | 沃斯坦热力设备（天津）有限公司 | A tube sheet assembly structure for hydrophily jie's fluoroplastics gas gas heater |
| CN205352115U (en) * | 2015-12-24 | 2016-06-29 | 科洋环境工程（上海）有限公司 | Glass pipe anticorrosion heat exchanger |
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| Title |
|---|
| 吴国贞等: "《塑料在化学工业中应用》", 31 August 1985, 化学工业出版社 * |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108889130A (en) * | 2018-06-26 | 2018-11-27 | 湖州科滤膜技术有限公司 | A kind of membrane separation plant that security performance is high connection protection pipe |
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|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20170714 |
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| RJ01 | Rejection of invention patent application after publication |