DK160726B - RIBBEROER AND APPARATUS FOR ITS MANUFACTURING. - Google Patents
RIBBEROER AND APPARATUS FOR ITS MANUFACTURING. Download PDFInfo
- Publication number
- DK160726B DK160726B DK311378A DK311378A DK160726B DK 160726 B DK160726 B DK 160726B DK 311378 A DK311378 A DK 311378A DK 311378 A DK311378 A DK 311378A DK 160726 B DK160726 B DK 160726B
- Authority
- DK
- Denmark
- Prior art keywords
- ribs
- pipe
- rib
- tube
- tool
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
- B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
- B21C37/15—Making tubes of special shape; Making tube fittings
- B21C37/20—Making helical or similar guides in or on tubes without removing material, e.g. by drawing same over mandrels, by pushing same through dies ; Making tubes with angled walls, ribbed tubes and tubes with decorated walls
- B21C37/207—Making helical or similar guides in or on tubes without removing material, e.g. by drawing same over mandrels, by pushing same through dies ; Making tubes with angled walls, ribbed tubes and tubes with decorated walls with helical guides
-
- 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
- F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
- F28F1/34—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending obliquely
- F28F1/36—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending obliquely the means being helically wound fins or wire spirals
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)
- Rigid Pipes And Flexible Pipes (AREA)
- Forging (AREA)
Description
DK 160726 BDK 160726 B
iin
Opfindelsen angår et ribberør til varmevekslere ifølge indledningen til krav 1 og et apparat til fremstilling heraf ifølge indledningen til krav 5.The invention relates to a rib tube for heat exchangers according to the preamble of claim 1 and an apparatus for making them according to the preamble of claim 5.
5 Et ribberør af den navnte art ifølge tysk offentliggørelsesskrift nr. 15 01 656 har over ribbeperiferien fordelte, i rørlængderetningen rettede i ndskær i nger i ribberne og dermed følgende ulemper: 10 Bortset fra, at et sådant rør giver anledning til vanskeligheder ved oplagring og transport såvel som ved installation i rørbundene og støtteplader for varmevekslere af rørbundttypen, bliver mellemrummet mellem længere oppe anbragte rør, ved anvendelse af sådanne rør i rørbundtfordampere, optaget af nede-15 fra opstigende bobler, så at en upåklagelig varmeoverføring bliver forhindret. Endvidere kan opstigende bobler trænge ind i de vide åbninger i mellemrummet mellem ved siden af hinanden liggende indskæringer og blokere fordampningsfladerne.5 A rib tube of the kind named according to German Publication No. 15 01 656 has distributed over the rib periphery, in the longitudinal direction of the ribs and in the ribs, and thus has the following disadvantages: 10 Except that such a tube causes difficulties in storage and transport as well as when installed in the tubes and support plates for tube-type heat exchangers, the space between longer pipes, using such tubes in tube bundle evaporators, is taken up by down-rising bubbles so that an impeccable heat transfer is prevented. Furthermore, rising bubbles can penetrate the wide openings in the gap between adjacent notches and block the evaporating surfaces.
20 Det er derfor et formål med opfindelsen at udforme et ribberør af den nævnte art således, at de mekaniske, håndteringsmæssige og termiske egenskaber bliver forbedret, især ved fordampning.It is therefore an object of the invention to design a rib tube of the kind mentioned so that the mechanical, handling and thermal properties are improved, especially by evaporation.
Dette formål opnås ifølge opfindelsen ved hjælp af de i den 25 kendetegnende del af krav 1 angivne træk.This object is achieved according to the invention by means of the features specified in the characterizing part of claim 1.
På denne måde opnås et ribberør med T-formede ribber med udglattet overflade, som er let at stable og transportere, og som lettere lader sig indskyde i rørbundene eller øvrige fik-30 seringer; thi forskellen mellem den ydre diameter af de ribbefri ender og ribbediameteren er mange gange større end ved sædvanlige ribberør.In this way, a ribbed tube with T-shaped ribs having a smooth surface is obtained, which is easy to stack and transport, and which is more easily insertable into the tube bottoms or other fixings; for the difference between the outer diameter of the rib-free ends and the rib diameter is many times greater than that of conventional rib pipes.
Ribberør af denne art har desuden vigtige fordele i forhold 35 til kendte rør:Ribbed tubes of this kind also have important advantages over 35 known tubes:
Ribbeenderne, som ved sædvanlige ribberør er delvis ru og delvis behæftet med revner, er gjort stærkere og glatvalsede, ! 2The ribs, which in the ordinary ribs are partly rough and partly cracked, are made stronger and smooth rolled,! 2
DK 160726 BDK 160726 B
dvs. rørene er mere utilbøjelige til at få revner og virker således bedre under skiftende mekaniske belastninger. En revneforplantning er derfor forhindret.i.e. the pipes are more prone to cracking and thus work better under changing mechanical loads. A crack propagation is therefore prevented.
5 Varmeoverføri ngen gennem rørene i følge opfi ndel sen er ved for dampningen væsentligt forbedret, da fordampningen af væsken overvejende finder sted i hulrummene mellem de T-formede ribber. Den fordampede væske bliver kontinuerligt erstattet af i spalten mellem ribberne indtrængende væske. Bobledannelsen 10 bliver ikke afbrudt, da relativt små bobler løbende kan frigøre sig og der til stadighed forbliver boblerester i hulrummet, så at det til dannelse af nye bobler nødvendige kimdannelsesarbejde bliver minimalt.The heat transfer through the tubes according to the invention is substantially improved for the steaming, since the evaporation of the liquid takes place predominantly in the cavities between the T-shaped ribs. The evaporated liquid is continuously replaced by fluid entering the gap between the ribs. Bubble formation 10 is not interrupted as relatively small bubbles can continuously release themselves and bubble remains remain in the cavity, so that the nucleation work needed to form new bubbles becomes minimal.
15 Især hvis man anvender rørene i rørbundtf ordampere, kan de nedefra opstigende tilvoksende bobler ikke længere trænge ind i mellemrummene mellem højere oppe anbragte rør og i stedet for ruller de forbi disse rør, således at også disse rør står til rådighed for fordampningen med hele deres flade.15 In particular, if the tubes are used in tube bundle vapors, the bottom-up rising bubbles can no longer penetrate the spaces between higher upstream tubes and instead they roll past these tubes, so that these tubes are also available for evaporation with their entire fleet.
2020
Apparatet til udøvelse af fremgangsmåden ifølge opfindelsen tager sit udgangspunkt i det fra DE-OS 1.501.656 kendte apparat og er ejendommeligt ved de i krav 5 angivne træk. For at opnå en god stukning af ribberne har stukningsværktøjet for-25 trinsvis en i rørgennemløbsretningen mod røret rettet skrå flade (krav 6).The apparatus for carrying out the method according to the invention is based on the apparatus known from DE-OS 1.501.656 and is peculiar to the features of claim 5. In order to obtain a good stretching of the ribs, the stretching tool preferably has an inclined surface directed in the pipe passage towards the pipe (claim 6).
Denne stukning eller glatning virker som en art udretningsproces, således at røret bliver bemærkelsesværdigt ret. Den 30 kendte fare for beskadigelse på grund af skarpe og ru ribbekanter ved arbejde med og på sådanne rør vil derved blive stærkt formindsket.This stretching or smoothing acts as a kind of straightening process, so that the tube becomes remarkably straight. The known risk of damage due to sharp and rough rib edges when working with and on such pipes will thereby be greatly reduced.
Som det er kendt bliver den indre overflade af et ribberør, 35 som er blevet valset, mere bølget, jo mere rørvæggens tykkelse formindskes. Denne bølgeform, som forårsages af den radiale materialeflydning ved valsningen af ribberne, vil blive for 3As is known, the inner surface of a rib tube 35 which has been rolled becomes more wavy, the more the thickness of the tube wall decreases. This waveform caused by the radial flow of material during the rolling of the ribs will become too 3
DK 160726 BDK 160726 B
mindsket ved den efterfølgende stukn i ngsproces. Man opnår således en indre overflade, der er væsentlig mindre strøm-ni ngstabsgi vende.diminished by the subsequent part of the process. Thus, an inner surface is obtained which is substantially less fluid loss.
5 Udformningen af apparatet afhænger af, om røret skal rotere eller skal holdes stationært, dvs. ikke skal rotere.5 The design of the apparatus depends on whether the tube should rotate or be held stationary, ie. not to rotate.
Således angår underkravene 7 og 8 fordelagtige udførelsesformer for apparatet med roterende rør.Thus, the subclaims 7 and 8 relate to advantageous embodiments of the rotary tube apparatus.
1010
Ved udførelsesformen ifølge krav 7 løber ribberne derved ind imod den excentrisk anbragte bøsning, dyse eller et lignende organ og bliver derved stukket. Valsehovedmidteraksen er i dette tilfælde identisk med rørmidteraksen.In the embodiment according to claim 7, the ribs thereby run against the eccentrically arranged bushing, nozzle or similar means and are thereby stung. In this case, the roll center axis is identical to the tube center axis.
1515
Ved udførelsesformen ifølge krav 8 får trykrullerne i form af slæberuller den nødvendige egendrejning som slæberuller ved rørets rotation.In the embodiment according to claim 8, the rollers in the form of drag rollers receive the necessary self-rotation as drag rollers in the rotation of the pipe.
20 Såvel ved roterende som ved ikke-roterende rør anbefales en udformning af apparatet som angivet i krav 9. På denne måde opnår man den fordel, at den uvirksomme zone for de T-formede ribber bliver væsentlig formindsket.In the case of both rotating and non-rotating pipes, an arrangement of the apparatus as claimed in claim 9. is recommended, in this way the advantage is obtained that the inert zone of the T-shaped ribs is substantially reduced.
25 I det følgende forklares opfindelsen nærmere ved hjælp af udførelseseksempler og under henvisning til tegningen, hvor fig. 1 viser en del af et ribberør med T-formede ribber ifølge opfindelsen set fra siden i snit, 30 fig. 2 et ribberør med T-formede ribber ifølge opfindelsen set fra siden delvis i snit, fig. 3 et apparat ifølge opfindelsen til anvendelse ved et 35 roterende rør set fra si den delvis i snit, og fig. 4 et apparat ifølge opfindelsen til anvendelse ved et roterende eller et fast rør set fra siden delvis i snit.25 In the following, the invention will be explained in more detail by way of examples and with reference to the drawing, in which fig. 1 is a sectional side view of a sectional rib with tubular ribs according to the invention; FIG. 2 is a side view, partly in section, of a T-shaped rib according to the invention; FIG. 3 is a partial sectional view of an apparatus according to the invention for use with a rotary tube, and FIG. 4 shows an apparatus according to the invention for use with a rotary or fixed side view partly in section.
DK 160726 8 4DK 160726 8 4
Fig. 1 og 2 viser et ribberør 1 ifølge opfindelsen. De T-for-mede ribber eller finner 2 løber rundtgående som en skruelinie på røret med konstant T-formet ribbetværsnit. Foden 3 af ribberne 2 strækker sig udad i radial retning fra rørvæggen 4, 5 medens ribbeenderne 5 er således stukkede, at de er glat udformede og ligger på en tænkt, med rørmidteraksen koaksial cylinderflade. Således opstår der indsnævrede render 6 (se den øvre rendebredde A i fig. 2). Afstanden mellem ribberne 2 varierer kontinuerligt, således at der imellem ribberne er dan-10 net i hovedsagen afrundede hulrum.FIG. 1 and 2 show a rib tube 1 according to the invention. The T-shaped ribs or fins 2 run circumferentially as a helical line on the tube with a constant T-shaped rib cross section. The foot 3 of the ribs 2 extends outwardly in radial direction from the tube wall 4, 5, while the ribs 5 are knit so that they are smoothly formed and lie on a conceived coaxial cylinder surface with the tube center axis. Thus, narrowed grooves 6 occur (see upper gutter width A in Fig. 2). The distance between the ribs 2 varies continuously, so that between the ribs, substantially rounded cavities are formed.
Varmetekniske fordele fremgår uden videre af følgende eksempel : 15 Der benyttedes et glat rør af SF-Cu med 19 mm udvendig diameter og 1,45 mm vægtykkelse. Med et kendt ribberørvalseapparat frembragtes et ribberør med 7,5 ribber/cm, en udvendig diameter på 18,9 mm og en ribbehøjde på 1,45 mm. Med det i udførelseseksemplet beskrevne apparat fremkom der et ribberør med en 20 udvendig diameter på 18,4 mm, en højde af de T-formede ribber på 1,2 mm og en rendebredde på 0,3 mm.Thermal engineering advantages are readily apparent from the following example: 15 A smooth pipe of SF-Cu with 19 mm outside diameter and 1.45 mm wall thickness was used. With a known rib tube roll apparatus, a rib tube of 7.5 ribs / cm, an outside diameter of 18.9 mm and a rib height of 1.45 mm was produced. With the apparatus described in the embodiment, a rib tube having an outside diameter of 18.4 mm was obtained, a height of the 1.2 mm T-shaped ribs and a channel width of 0.3 mm.
Et sådant rør resulterede ved f.eks. 2,0 m/sek. vandhastighed i røret og fordampning af kølemidlet "R12" på rørydersiden 10% 25 større ydelse ved 2,5 m/sek. 20% og ved 3 m/sek. 30% større ydelse. (Her er kun vist et valseværktøj 7). Man kan f.eks. bruge tre, fire eller seks valseværktøjer 7 bestående af valseskiver 8. Valseværktøjerne 7 er radialt sammenbringelige. Valseskiverne 8 er lejret i en værktøjsholder 9. De centrisk i 30 forhold til rørmidteraksen anbragte valseværktøjer 7 danner på kendt måde ribberne eller finnerne 2' af den ved hjælp af en dornstang 10 understøttede rørvæg 4. På denne måde tilvejebringes der først i et forreste område (indtrækningsområdet) en formindskelse af diameteren. I et midterste område (færdig-35 valseområdet) fremstilles ved valsning de skruel inieformede rundtgående ribber 2'. Umiddelbart efter valseværktøjerne 7 er koblet et stukkeværktøj 11, hvis akse er forskudt excentrisk iSuch a tube resulted in e.g. 2.0 m / sec. water velocity in the pipe and evaporation of the refrigerant "R12" on the pipe exterior 10% 25 greater performance at 2.5 m / sec. 20% and at 3 m / sec. 30% greater performance. (Only one roller tool 7 is shown here). One can, for example. use three, four or six rolling tools 7 consisting of rolling discs 8. The rolling tools 7 are radially foldable. The roller discs 8 are housed in a tool holder 9. The centrally positioned roller tools 7 formed in a known manner relative to the pipe center axis 7 form the ribs or fins 2 'of the pipe wall 4 supported by a mandrel rod 10. (retraction area) a decrease in diameter. In a middle region (the finished roller region), by rolling, the helical non-circular ribs 2 'are produced. Immediately after the rolling tools 7 is coupled a cutting tool 11, the axis of which is offset eccentrically in
Claims (10)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2735762A DE2735762C2 (en) | 1977-08-09 | 1977-08-09 | Finned tube and device for its manufacture |
DE2735762 | 1977-08-09 |
Publications (3)
Publication Number | Publication Date |
---|---|
DK311378A DK311378A (en) | 1979-02-10 |
DK160726B true DK160726B (en) | 1991-04-08 |
DK160726C DK160726C (en) | 1991-09-23 |
Family
ID=6015929
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DK311378A DK160726C (en) | 1977-08-09 | 1978-07-11 | RIBBEROER AND APPARATUS FOR ITS MANUFACTURING. |
Country Status (9)
Country | Link |
---|---|
JP (1) | JPS5499253A (en) |
AT (1) | AT358612B (en) |
DE (1) | DE2735762C2 (en) |
DK (1) | DK160726C (en) |
ES (1) | ES244808Y (en) |
FR (1) | FR2400179A1 (en) |
GB (1) | GB2002893B (en) |
IT (1) | IT1105441B (en) |
SE (1) | SE448780B (en) |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2808080C2 (en) * | 1977-02-25 | 1982-12-30 | Furukawa Metals Co., Ltd., Tokyo | Heat transfer tube for boiling heat exchangers and process for its manufacture |
US4313248A (en) * | 1977-02-25 | 1982-02-02 | Fukurawa Metals Co., Ltd. | Method of producing heat transfer tube for use in boiling type heat exchangers |
DE2758527C2 (en) * | 1977-12-28 | 1985-04-25 | Wieland-Werke Ag, 7900 Ulm | Method and device for manufacturing a finned tube |
DE2758526C2 (en) * | 1977-12-28 | 1986-03-06 | Wieland-Werke Ag, 7900 Ulm | Method and device for manufacturing a finned tube |
DE2803273A1 (en) * | 1978-01-26 | 1979-08-02 | Wieland Werke Ag | FIBER TUBE AND THE METHOD AND DEVICE FOR THE PRODUCTION THEREOF |
DE2803274A1 (en) * | 1978-01-26 | 1979-08-02 | Wieland Werke Ag | FIBER TUBE AND THE METHOD AND DEVICE FOR THE PRODUCTION THEREOF |
JPS59202397A (en) * | 1983-04-30 | 1984-11-16 | Kobe Steel Ltd | Internally grooved pipe and manufacture thereof |
US4619314A (en) * | 1983-08-05 | 1986-10-28 | Ishikawajima-Harima Jukogyo Kabushiki Kaisha | Device for preventing wear of heat transfer tubes in fluidized-bed boiler |
DE3408626A1 (en) * | 1984-03-09 | 1985-09-12 | Wieland-Werke Ag, 7900 Ulm | Wound heat exchanger, in particular for heat pumps or refrigerating plants |
IT1198211B (en) * | 1985-12-02 | 1988-12-21 | Carrier Corp | METHOD AND APPARATUS TO PRODUCE EXTERNALLY PERFECTED PIPES USING MULTIPLE HELICAL PITCH PRINCIPLES |
US4997341A (en) * | 1989-08-15 | 1991-03-05 | Bw/Ip International, Inc. | Reduction of transient thermal stresses in machine components |
DE10150999C2 (en) | 2001-10-16 | 2003-08-07 | Peak Werkstoff Gmbh | Method of profiling the outer peripheral surface of cylinder liners |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3326283A (en) * | 1965-03-29 | 1967-06-20 | Trane Co | Heat transfer surface |
US3383892A (en) * | 1965-08-13 | 1968-05-21 | Anaconda American Brass Co | Manufacture of integrally finned tubing |
GB1092150A (en) * | 1965-10-19 | 1967-11-22 | Bjorn Large | A method of producing ribbed tubes of deformable material |
US3602027A (en) * | 1969-04-01 | 1971-08-31 | Trane Co | Simultaneous finning and reforming of tubular heat transfer surface |
US3683656A (en) * | 1970-03-25 | 1972-08-15 | Carl M Lewis | Heat exchanger apparatus and method of making the same |
-
1977
- 1977-08-09 DE DE2735762A patent/DE2735762C2/en not_active Expired
-
1978
- 1978-07-04 GB GB7828769A patent/GB2002893B/en not_active Expired
- 1978-07-05 AT AT488678A patent/AT358612B/en not_active IP Right Cessation
- 1978-07-11 DK DK311378A patent/DK160726C/en not_active IP Right Cessation
- 1978-07-21 SE SE7808061A patent/SE448780B/en not_active IP Right Cessation
- 1978-08-01 ES ES1978244808U patent/ES244808Y/en not_active Expired
- 1978-08-09 IT IT50678/78A patent/IT1105441B/en active
- 1978-08-09 JP JP9717078A patent/JPS5499253A/en active Pending
- 1978-08-09 FR FR7823492A patent/FR2400179A1/en not_active Withdrawn
Also Published As
Publication number | Publication date |
---|---|
ES244808U (en) | 1980-06-16 |
JPS5499253A (en) | 1979-08-04 |
SE448780B (en) | 1987-03-16 |
AT358612B (en) | 1980-09-25 |
IT1105441B (en) | 1985-11-04 |
GB2002893A (en) | 1979-02-28 |
GB2002893B (en) | 1982-05-26 |
DK311378A (en) | 1979-02-10 |
DE2735762A1 (en) | 1979-02-22 |
DK160726C (en) | 1991-09-23 |
IT7850678A0 (en) | 1978-08-09 |
FR2400179A1 (en) | 1979-03-09 |
ATA488678A (en) | 1980-02-15 |
SE7808061L (en) | 1979-02-10 |
DE2735762C2 (en) | 1983-11-24 |
ES244808Y (en) | 1980-12-01 |
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Legal Events
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PBP | Patent lapsed |