DK149993B - PROCEDURE FOR SHAPING A SPRAY MOLDED PIPE - Google Patents
PROCEDURE FOR SHAPING A SPRAY MOLDED PIPE Download PDFInfo
- Publication number
- DK149993B DK149993B DK36577A DK36577A DK149993B DK 149993 B DK149993 B DK 149993B DK 36577 A DK36577 A DK 36577A DK 36577 A DK36577 A DK 36577A DK 149993 B DK149993 B DK 149993B
- Authority
- DK
- Denmark
- Prior art keywords
- head
- sleeve
- recess
- groove
- tube
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/0053—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor combined with a final operation, e.g. shaping
- B29C45/0055—Shaping
-
- 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
- F16L47/00—Connecting arrangements or other fittings specially adapted to be made of plastics or to be used with pipes made of plastics
- F16L47/06—Connecting arrangements or other fittings specially adapted to be made of plastics or to be used with pipes made of plastics with sleeve or socket formed by or in the pipe end
- F16L47/08—Connecting arrangements or other fittings specially adapted to be made of plastics or to be used with pipes made of plastics with sleeve or socket formed by or in the pipe end with sealing rings arranged between the outer surface of one pipe end and the inner surface of the sleeve or socket, the sealing rings being placed previously in the sleeve or socket
Description
i 149993in 149993
Opfindelsen angår en fremgangsmåde til formning af et sprøjtestøbt mufferør af plast med en indvendig rille og en i denne rille optaget ringformet del af et tætningslegeme, hvilken rille er begrænset af et aksialt og radialt forløbende hoved 5 og indbefatter en aksial reces, som strækker sig ind i et fortykket vægparti beliggende ved enden af mufferøret mellem dennes inderside og yderside.BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method of forming a plastic injection molded sleeve tube with an inner groove and an annular portion of a sealing body accommodated in this groove, which groove is limited by an axially and radially extending head 5 and includes an axial recess extending into it. in a thickened wall portion located at the end of the sleeve tube between the inside and outside thereof.
Det er kendt at fremstille mufferør af den indledningsvis 10 nævnte type. Hvis en endedel af et hoved på et sprøjtestøbt rør deformeres indad, således som vist i fig. 3, vil der efter afkølingen være store spændinger til stede inden for denne deformerede del, da denne deformerede del vil forsøge at gen-indtage dens oprindelige position (fig. 2) på grund af plast-15 materialernes egenskaber.It is known to manufacture sleeve pipes of the type mentioned initially. If an end portion of a head of an injection molded tube is deformed inwardly, as shown in FIG. 3, after cooling, large stresses will be present within this deformed portion, as this deformed portion will attempt to regain its original position (Fig. 2) due to the properties of the plastics materials.
Når et ekstruderet rør er tildannet med en endeudvidelse, vil en deformation af endedelen i retning indad ikke indebære dannelsen af høje spændinger, da den deformerede del vil forsøge 20 at genindtage dens oprindelige position, hvilket netop i dette tilfælde vil sige, at den udvidede del vil foretage en indadgående bevægelse.When an extruded tube is formed with an end extension, a deformation of the end portion inwardly will not involve the formation of high stresses, as the deformed portion will attempt to regain its original position, which is precisely in this case the extended portion. will make an inward movement.
Fra US-patentskrift nr. 3.544.119 kendes en muffeende med en 25 reces til optagelse af et tætn ings1 egerne. Tætningslegemet fastholdes i recessen ved hjælp af en separat holdering, som forbindes med muffeenden.US Patent No. 3,544,119 discloses a sleeve end having a recess for receiving a sealing spokes. The sealing body is retained in the recess by a separate retainer which is connected to the sleeve end.
GB-patentskrift nr. 1.227.309 angår et mufferør af den indled-30 ningsvis nævnte art, idet der dog ikke findes nogen reces til optagelse af tætningslegemet. Dertil kommer, at endedelen af mufferøret har en radialt forløbende hoveddel, som er hængslet forbundet med den øvrige del af hovedet, hvorfor der er fare for, at tætningslegemet kan blive revet ud af den optagende 3 5 r i 11e.GB Patent No. 1,227,309 relates to a sleeve tube of the type mentioned in the preamble, although no recess exists for receiving the sealing body. In addition, the end portion of the sleeve tube has a radially extending head portion which is hingedly connected to the other portion of the head, which is why there is a danger that the sealing body may be torn out of the receiving tube in 11e.
Fremgangsmåden ifølge opfindelsen er ejendommelig ved, at den ringformede del anbringes delvis i den aksiale reces, hvoref 149993 2 ter enden af hovedet, som er tildannet ud i ét og er fast forbundet med mufferøret, plastificeres og deformeres på en sådan måde, at der af hovedet og recessen dannes en rille, som er fuldstændig udfyldt af den ringformede del af tætningslegemet, 5 idet recessen i det fortykkede vægparti udformes med afrundede kanter, og den radialt indadbøjede hoveddel afrundes i området, hvor hovedets radialt forløbende del går over i dets ikke-radiale del. Herved opnås, at tætningslegemet ved hjælp af den ringformede del, der helt udfylder rillen inklusive re-10 cessen, fastholdes sikkert, og at denne indlejring opnås på simpel måde ved ombukning af det radialt forløbende hoved, når den yderste ende af muffen er plastificeret. Tætningslegemet lader sig herved hensigtsmæssigt anbringe på plads på det sted, hvor mufferøret fremstilles, hvorved sikres særlig god 15 sikkerhed for, at den endelige rørsamling bliver lækagefri.The method according to the invention is characterized in that the annular part is placed partially in the axial recess, whereby the end of the head, which is integrally formed and fixedly connected to the sleeve tube, is plasticized and deformed in such a way that the head and recess form a groove which is completely filled by the annular portion of the sealing body, the recess in the thickened wall portion being formed with rounded edges and the radially inwardly bent body portion being rounded in the region where the radially extending portion of the head extends into its non-shaped portion. radial part. Hereby, by means of the annular portion which completely fills the groove including the recess, the sealing body is securely retained, and this embedding is accomplished in a simple manner by bending the radially extending head when the outer end of the sleeve is plasticized. Consequently, the sealing body is conveniently placed in place at the place where the socket pipe is manufactured, thereby ensuring particularly good assurance that the final pipe assembly will be leak-free.
Til trods for de høje spændinger, der forventes ved indadgående deformation af endedelen i det sprøjtestøbte mufferør og dermed de forventede alvorlige beskadigelser af den deformerede 20 del, hvis den rammer bunden under en kraftig slagbelastning, forekommer der overraskende ikke nogen ødelæggelser i det foreliggende tilfælde, antagelig på grund af den elastiske understøtning som den deformerede del bibringes ved hjælp af den ringformede del af tætningslegemet.Notwithstanding the high stresses expected from inward deformation of the end portion of the injection molded sleeve tube and thus the expected serious damage to the deformed portion if it strikes the bottom under a heavy impact load, there is surprisingly no damage in the present case. presumably due to the elastic support provided by the deformed portion by the annular portion of the sealing body.
2525
Opfindelsen forklares nærmere i det følgende i forbindelse med en udførelsesform for mufferøret ifølge opfindelsen og under henvisning til tegningen, hvor 30 Fig. 1 viser et længdesnit gennem et plast-mufferør ifølge opfindelsen,The invention will be further explained in the following with reference to an embodiment of the sleeve pipe according to the invention and with reference to the drawing, in which FIG. 1 is a longitudinal section through a plastic sleeve tube according to the invention,
Fig. 2 en del af den ene ende af et sprøjtestøbt mufferør med et dermed forbundet hoved, 35FIG. 2 is a portion of one end of an injection molded sleeve tube with an associated head, 35
Fig. 3 den samme ende af et sprøjtestøbt mufferør efter radial deformering af hovedet og indbukning af den radialt ombøjede del af hovedet, og 3 149993FIG. 3 shows the same end of an injection molded sleeve tube after radial deformation of the head and bending of the radially bent portion of the head, and 3
Fig. 4 den i fig. 2 viste rørende efter kun radial deforme-ring af hoveddelen, og med enden af et andet rør indsat i muffen.FIG. 4 is the one shown in FIG. 2 after only radially deforming the main body and with the end of another tube inserted into the sleeve.
55
Fig. 1 viser et mufferør 1 med to muffer og fremstillet ved ekstrudering af termoplastisk materiale, såsom polyvinylchlo-rid. Røret har en muffedel 2a ved hver ende og en indvendig stopflange 16 mellem disse. I en rille 3 er optaget en ring-10 formet del 4 af et tætningslegeme 18, hvilken ringformet del 4 udgør en integrerende del af en pakningsmuffe 5. Muffeenden 2, som er forsynet med rillen, har desuden en større indvendig diameter end muffedelen 2a. Muffeenden 2 tjener til at tilpasse tætningslegemets 18 pakningsmuffe 5, når en glat ende 21 af 15 et rør skubbes ind i muffedelen 2a, således at pakningsmuffen 5 kommer til at ligge tætnende an imod den glatte ende 21, samtidig med at den udvendige diameter af den glatte ende 21 er i hovedsagen lig med den indvendige diameter af muffedelen 2a ved indervæggen 17.FIG. 1 shows a sleeve tube 1 with two sleeves and made by extruding thermoplastic material such as polyvinyl chloride. The tube has a sleeve portion 2a at each end and an inner stop flange 16 therebetween. In a groove 3 is provided an annular portion 4 of a sealing body 18, which annular portion 4 forms an integral part of a gasket sleeve 5. The sleeve end 2 provided with the groove also has a larger internal diameter than the sleeve portion 2a. The sleeve end 2 serves to fit the gasket sleeve 5 of the sealing body 18 as a smooth end 21 of 15 pushes a tube into the sleeve portion 2a so that the gasket sleeve 5 seals against the smooth end 21 while maintaining the outer diameter of the sleeve. smooth end 21 is substantially equal to the inner diameter of the sleeve portion 2a at the inner wall 17.
2020
Rillen 3, som skal optage den ringformede del 4, indbefatter en reces 6, der er anbragt i en fortykket vægdel 7 af muffeenden 2, hvilken vægdel 7 strækker sig mellem muffens indervæg 8 og en ydervæg 9 af et hoved 10, som er ført ud forbi den fri 25 ende 11 af muffeenden 2.The groove 3, which is to receive the annular portion 4, includes a recess 6 disposed in a thickened wall portion 7 of the sleeve end 2, which wall portion 7 extends between the inner wall 8 of the sleeve and an outer wall 9 of a head 10 which is extended out. past the free end 25 of the sleeve end 2.
Recessen 6 i den fortykkede vægdel 7 har afrundede kanter.Recess 6 of thickened wall portion 7 has rounded edges.
Til dannelse af rillen deformeres en endedel 19 af hovedet 10 30 i radial retning på en sådan måde, at den efter deformeringen strækker sig indad, fortrinsvis i radial retning. Til opnåelse af gode styrkeegenskaber under formningen af endedelen er det vigtigt at sikre en god afrunding ved 12 på ydersiden af muffeenden ved overgangen mellem den radialt indadbøjede endedel 35 19 af hovedet 10 og det færdige mufferørs ydervæg 9.To form the groove, an end portion 19 of the head 10 is deformed in a radial direction such that it extends inwardly after the deformation, preferably in the radial direction. In order to obtain good strength properties during shaping of the end portion, it is important to ensure a good rounding at 12 on the outside of the sleeve end at the transition between the radially inwardly bent end portion 19 of the head 10 and the outer sleeve tube 9.
Den yderste ende 15 af hovedets 10 endedel 19 kan med fordel bøjes lidt indad, hvorved åbningen 13 mellem den fri ende 11 149993 4 af muffen og enden 15 af den radialt bøjede endedel 19 på hovedet 10 reduceres, således at man undgår at den ringformede del 4 af tætningslegemet 18 trækkes ud under påvirkning af trækkræfter.Advantageously, the outer end 15 of the end portion 19 of the head 10 may bend slightly inwardly, thereby reducing the opening 13 between the free end 11 of the sleeve and the end 15 of the radially bent end portion 19 of the head 10, so as to avoid the annular portion. 4 of the sealing body 18 is pulled out under the influence of tensile forces.
55
Ved fremstilling af et sprøjtestøbt mufferør ifølge opfindelsen dannes et mufferør ved sprøjtestøbning, hvorefter det opvarmes partielt, f.eks. med varm luft, ved hjælp af olie eller ved hjælp af ultralydvibrationer, således at i det mindste en 10 del af hovedet 10 opnår en temperatur, ved hvilken denne del af røret kan formgives. Til dette formål kommer temperaturer på f.eks. mellem 120 og 200°C i betragtning, når der anvendes polyvinylchlorid.In the manufacture of an injection molded sleeve tube according to the invention, a sleeve tube is formed by injection molding and then partially heated, e.g. with hot air, by means of oil or by ultrasonic vibration, so that at least one part of the head 10 achieves a temperature at which this part of the tube can be shaped. For this purpose, temperatures of e.g. between 120 and 200 ° C when using polyvinyl chloride.
15 Det apparat, der benyttes til formgivning af hovedet 10, og som kan udføres af en form med fremspringende kant, må fortrinsvis være opvarmet f.eks. til en temperatur over 50°C for at undgå, at den radialt bøjede del af hovedet bliver skør, hvilket indvirker meget uheldigt på rørets styrkeegenskaber.The apparatus used for shaping the head 10, which can be made of a protruding edge shape, must preferably be heated e.g. to a temperature above 50 ° C to prevent the radially bent portion of the head from becoming brittle, which has a very adverse effect on the strength properties of the tube.
2020
Ved opvarmning af hovedet, som skal bukkes radialt indad, er det vigtigt at sikre en sådan opvarmning af hovedet 10, at det overalt opnår den ønskede plastificeringstemperatur for at man kan opnå de bedst mulige styrkeegenskaber i det færdige pro-25 dukt.When heating the head, which is to be radially bent inwardly, it is important to ensure such heating of the head 10 that it achieves the desired plasticization temperature everywhere in order to obtain the best possible strength properties in the finished product.
Allerede før formgivningen af hovedet 10 kan det være hensigtsmæssigt at anbringe den ringformede del 4 af tætningslegemet 18 i recessen 6, hvorefter man ved radial ombøjning af hove-.30 dets 10 endedel 19 kan opnå den ønskede fastgørelse af den ringformede del 4.Even before shaping the head 10, it may be convenient to place the annular portion 4 of the sealing body 18 in the recess 6, after which the desired attachment of the annular portion 4 can be obtained by radially bending the end portion 19 of the head 30.
Ved røret ifølge opfindelsen er det en særlig fordel, at der kan anvendes simple sprøjtestøbeforme til fremstilling af ud-35 gangsproduktet, hvorfra det sprøjtestøbte mufferør kan formes ved anvendelse af meget simple redskaber.In the pipe according to the invention, it is a particular advantage that simple injection molds can be used to make the starting product, from which the injection molded sleeve pipe can be formed using very simple tools.
Ved formgivningen af hovedets 10 endedel 19 er det hensigtsmæssigt at afrunde indersiden af overgangspartiet (ved 14) mellemIn shaping the end portion 19 of the head 10, it is convenient to round the inside of the transition portion (at 14) between
Claims (2)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL7600928 | 1976-01-29 | ||
| NL7600928A NL170048B (en) | 1976-01-29 | 1976-01-29 | METHOD FOR MANUFACTURING AN INJECTION MOLDED TUBE. |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| DK36577A DK36577A (en) | 1977-07-30 |
| DK149993B true DK149993B (en) | 1986-11-10 |
| DK149993C DK149993C (en) | 1987-06-29 |
Family
ID=19825534
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK36577A DK149993C (en) | 1976-01-29 | 1977-01-28 | PROCEDURE FOR SHAPING A SPRAY MOLDED PIPE |
Country Status (12)
| Country | Link |
|---|---|
| JP (2) | JPS52115425A (en) |
| AT (1) | AT354198B (en) |
| BE (1) | BE850832A (en) |
| DE (1) | DE2703300C3 (en) |
| DK (1) | DK149993C (en) |
| ES (1) | ES455466A1 (en) |
| FR (1) | FR2339801A1 (en) |
| GB (1) | GB1547082A (en) |
| IE (1) | IE44418B1 (en) |
| IT (1) | IT1076350B (en) |
| NL (1) | NL170048B (en) |
| SE (1) | SE7700932L (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2717487C3 (en) * | 1977-04-20 | 1979-10-11 | Wavin B.V., Zwolle (Niederlande) | Extruded plastic pipe part with molded socket |
| DE2807022C2 (en) * | 1978-02-18 | 1982-07-01 | Fa. Carl Freudenberg, 6940 Weinheim | Sealing ring |
| NL7908625A (en) * | 1979-11-28 | 1981-07-01 | Wavin Bv | TUBE PART WITH ELASTIC SEALING BODY. |
| ZA824401B (en) * | 1981-06-22 | 1983-04-27 | D Van Manen | A method of making socketed pipe-fittings of synthetic plastics material by injection moulding, apparatus for carrying out said method, and fitting produced by the method |
| DE3310226C2 (en) * | 1983-03-22 | 1985-08-22 | Friedrichsfeld Gmbh, Steinzeug- Und Kunststoffwerke, 6800 Mannheim | Pipe part or fitting |
| US4906010A (en) * | 1986-03-27 | 1990-03-06 | Multi Fittings Inc. | Joint for connecting a spigot to the bell of a pipe or coupling |
| DE4409137C1 (en) * | 1994-03-17 | 1995-09-14 | Teewen Bv | Pipe coupling |
| ITVA20050057A1 (en) * | 2005-10-14 | 2007-04-15 | Serio Plast Srl | PROCEDURE FOR THERMOPLASTIC MOLDING OF HYDRAULIC FITTINGS HOLDING AT LEAST A SEAL OF HERMETIC SEAL AND HYDRAULIC FITTINGS OBTAINED WITH THIS PROCEDURE |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH386192A (en) * | 1960-03-29 | 1964-12-31 | Rheinisches Metallwerk Gmbh | Connection sleeve, in particular for pipes made of plastic |
| GB911589A (en) * | 1960-12-20 | 1962-11-28 | Jarmuefejlesztesi Intezet | Silicone oil filled dynamic, torsional damper mainly for internal combustion engines |
| NL281193A (en) * | 1962-07-20 | |||
| US3544119A (en) * | 1968-04-01 | 1970-12-01 | Hepworth Iron Co Ltd | Pipe couplings |
| DE1805446C3 (en) * | 1968-07-18 | 1974-09-12 | Kunststoffwerk Gebr. Anger Gmbh & Co Muenchen, 8000 Muenchen | Method for producing a tubular body made of a thermoplastic material |
| GB1227309A (en) * | 1970-03-04 | 1971-04-07 | ||
| BE788403A (en) * | 1971-09-17 | 1973-01-02 | Bagnulo Luigi | PERFECTIONS TO RIGID JOINTS IN THE SHAPE OF A BOWL FOR GAS OR LIQUID PIPING |
| JPS5541045B2 (en) * | 1972-10-09 | 1980-10-22 | ||
| US3858914A (en) * | 1973-07-25 | 1975-01-07 | Brass Craft Mfg Co | Transition pipe connection |
-
1976
- 1976-01-29 NL NL7600928A patent/NL170048B/en not_active Application Discontinuation
-
1977
- 1977-01-27 GB GB345077A patent/GB1547082A/en not_active Expired
- 1977-01-27 DE DE19772703300 patent/DE2703300C3/en not_active Expired
- 1977-01-28 FR FR7702408A patent/FR2339801A1/en active Granted
- 1977-01-28 IT IT1973777A patent/IT1076350B/en active
- 1977-01-28 DK DK36577A patent/DK149993C/en not_active IP Right Cessation
- 1977-01-28 ES ES455466A patent/ES455466A1/en not_active Expired
- 1977-01-28 BE BE174441A patent/BE850832A/en not_active IP Right Cessation
- 1977-01-28 SE SE7700932A patent/SE7700932L/en not_active Application Discontinuation
- 1977-01-28 AT AT55877A patent/AT354198B/en not_active IP Right Cessation
- 1977-01-28 IE IE17977A patent/IE44418B1/en not_active IP Right Cessation
- 1977-01-29 JP JP827577A patent/JPS52115425A/en active Granted
-
1981
- 1981-04-27 JP JP56065083A patent/JPS5833436B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5833436B2 (en) | 1983-07-19 |
| SE7700932L (en) | 1977-07-30 |
| DK36577A (en) | 1977-07-30 |
| FR2339801B1 (en) | 1982-05-21 |
| JPS5718887A (en) | 1982-01-30 |
| ES455466A1 (en) | 1978-05-16 |
| DE2703300A1 (en) | 1977-08-11 |
| DE2703300C3 (en) | 1986-07-31 |
| IE44418B1 (en) | 1981-11-18 |
| JPS52115425A (en) | 1977-09-28 |
| DE2703300B2 (en) | 1980-01-24 |
| ATA55877A (en) | 1979-05-15 |
| GB1547082A (en) | 1979-06-06 |
| IE44418L (en) | 1977-07-29 |
| FR2339801A1 (en) | 1977-08-26 |
| DK149993C (en) | 1987-06-29 |
| AT354198B (en) | 1979-12-27 |
| BE850832A (en) | 1977-07-28 |
| NL170048B (en) | 1982-04-16 |
| IT1076350B (en) | 1985-04-27 |
| NL7600928A (en) | 1977-08-02 |
| JPS575995B2 (en) | 1982-02-02 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PBP | Patent lapsed |