CH365587A - Welded connection between two plastic pipes - Google Patents
Welded connection between two plastic pipesInfo
- Publication number
- CH365587A CH365587A CH6488458A CH6488458A CH365587A CH 365587 A CH365587 A CH 365587A CH 6488458 A CH6488458 A CH 6488458A CH 6488458 A CH6488458 A CH 6488458A CH 365587 A CH365587 A CH 365587A
- Authority
- CH
- Switzerland
- Prior art keywords
- pipe
- welded connection
- support ring
- plastic pipes
- socket
- 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
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
- B29C65/18—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools
- B29C65/20—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools with direct contact, e.g. using "mirror"
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/10—Particular design of joint configurations particular design of the joint cross-sections
- B29C66/12—Joint cross-sections combining only two joint-segments; Tongue and groove joints; Tenon and mortise joints; Stepped joint cross-sections
- B29C66/122—Joint cross-sections combining only two joint-segments, i.e. one of the parts to be joined comprising only two joint-segments in the joint cross-section
- B29C66/1222—Joint cross-sections combining only two joint-segments, i.e. one of the parts to be joined comprising only two joint-segments in the joint cross-section comprising at least a lapped joint-segment
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/10—Particular design of joint configurations particular design of the joint cross-sections
- B29C66/12—Joint cross-sections combining only two joint-segments; Tongue and groove joints; Tenon and mortise joints; Stepped joint cross-sections
- B29C66/122—Joint cross-sections combining only two joint-segments, i.e. one of the parts to be joined comprising only two joint-segments in the joint cross-section
- B29C66/1224—Joint cross-sections combining only two joint-segments, i.e. one of the parts to be joined comprising only two joint-segments in the joint cross-section comprising at least a butt joint-segment
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/10—Particular design of joint configurations particular design of the joint cross-sections
- B29C66/13—Single flanged joints; Fin-type joints; Single hem joints; Edge joints; Interpenetrating fingered joints; Other specific particular designs of joint cross-sections not provided for in groups B29C66/11 - B29C66/12
- B29C66/131—Single flanged joints, i.e. one of the parts to be joined being rigid and flanged in the joint area
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/32—Measures for keeping the burr form under control; Avoiding burr formation; Shaping the burr
- B29C66/322—Providing cavities in the joined article to collect the burr
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/50—General aspects of joining tubular articles; General aspects of joining long products, i.e. bars or profiled elements; General aspects of joining single elements to tubular articles, hollow articles or bars; General aspects of joining several hollow-preforms to form hollow or tubular articles
- B29C66/51—Joining tubular articles, profiled elements or bars; Joining single elements to tubular articles, hollow articles or bars; Joining several hollow-preforms to form hollow or tubular articles
- B29C66/52—Joining tubular articles, bars or profiled elements
- B29C66/522—Joining tubular articles
- B29C66/5221—Joining tubular articles for forming coaxial connections, i.e. the tubular articles to be joined forming a zero angle relative to each other
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/50—General aspects of joining tubular articles; General aspects of joining long products, i.e. bars or profiled elements; General aspects of joining single elements to tubular articles, hollow articles or bars; General aspects of joining several hollow-preforms to form hollow or tubular articles
- B29C66/63—Internally supporting the article during joining
- B29C66/636—Internally supporting the article during joining using a support which remains in the joined object
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/70—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
- B29C66/73—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset
- B29C66/739—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset
- B29C66/7392—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of at least one of the parts being a thermoplastic
- B29C66/73921—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of at least one of the parts being a thermoplastic characterised by the materials of both parts being thermoplastics
-
- 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
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/70—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
- B29C66/71—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the composition of the plastics material of the parts to be joined
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Lining Or Joining Of Plastics Or The Like (AREA)
- Branch Pipes, Bends, And The Like (AREA)
Description
Schweissverbindung zweier Kunststoffrohre
Vorliegende Erfindung betrifft eine Schweissverbindung zweier Kunststoffrohre, beispielsweise aus Polyäthylen.
Bisher war es üblich, Polyäthylenrohre und Muffen bzw. Fittings aus demselben Material miteinander zu verbinden, indem mit Hilfe eines Heizgerätes das Rohrende aussen und die Fittingmuffe innen auf Schweisstemperatur gebracht wurden, um anschlie ssend ineinandergeschoben zu werden. Bei dünnwandigen Rohren werden durch die vorstehende Operation aber nicht nur die Oberflächen der Rohrenden weich, sondern die ganze Wandung. Dadurch besitzen die Rohrenden zu wenig Festigkeit und Steifheit und fallen beim Einschieben in die Muffenenden in sich zusammen oder werfen sich wellenförmig auf.
Die Güte der Schweissung ist dadurch in Frage ge stellt. Sehr oft wird dadurch auch der Durchflussquerschnitt wesentlich herabgesetzt.
Die vorliegende Erfindung ermöglicht auch, dünnwandige Rohre einwandfrei zu verschweissen. Das Kennzeichen der Erfindung besteht darin, dass im Innern des Rohrendes ein Stützring vorgesehen ist, dessen Länge der abgesetzten Bohrung der Muffe angepasst ist, und welcher eine höhere Erweichungstemperatur besitzt als das Rohr. Als Material für den Stützring kann beispielsweise Polypropylen, Polyamid oder bestrahltes Hartpolyäthylen verwendet werden.
Die Figuren zeigen zwei verschiedene Ausführungsarten der Rohrverbindung gemäss der Erfindung, und zwar:
Fig. 1 das Aufheizen der Verbindung mittels eines rohrförmigen Schweiss- bzw. Heizgerätes im Schnitt,
Fig. 2 eine Bauart der Rohrverbindung im Schnitt,
Fig. 3 eine weitere Bauart der Rohrverbindung im Schnitt.
Fig. 1 zeigt als Beispiel einer Schweissvorrichtung ein abgesetztes Stahlrohr 1, welches wenig über die Schweisstemperatur des Kunststoffes aufgeheizt wird.
Sofern die Schweissvorrichtung 1 irgendwo fest eingespannt wird, kann die Muffe 2 und das Rohrende 3 gleichzeitig angeheizt werden. Damit bei dünnwandigen Rohren das Rohrende 3 beim Einschieben in die Muffe nicht zusammenfällt oder zusam2nenge- staucht wird, wird gemäss der Erfindung im Rohrende 3 ein Stützring 4 aus einem Kunststoff mit höherer Erweichungstemperatur eingesetzt. Die Schweissraupen 5 und 6 (Fig. 2) entstehen von selbst, durch Aufschieben von weichem Material.
Eine weitere Ausführungsart des Stützringes 7 ist in Fig. 3 dargestellt. Derselbe besitzt an seiner äusseren Kontur 8 einen Bund 9, welcher beim Einschieben des Rohres 3 in die Muffe 2 als Distanzring zwischen der Stirnwand 10 des Rohrendes 3 und dem Abstatz 11 der Muffe 2 eingeklemmt wird. Zwischen Rohrende 3 und Muffe 2 entsteht dadurch ein Hohlraum 13, der zur Aufnahme des beim Schweissen zwangläufig entstehenden überschüssigen Materials 12 dient.
Der Stützring 7 wird durch den Bund in seiner axialen Lage im Rohr 3 eindeutig festgelegt.
Als weitere Ausführungsarten können auch längsoder schräggeschlitzte, unter radialer Vorspannung stehende Stützringe verwendet werden.
Wichtig ist, dass die Stützringe 4, 7 aus einem Material hergestellt sind, welches einen höheren Erweichungspunkt besitzt als das Rohrmaterial. Die Stützringe können z. B. aus Polypropylen, Polyamid oder durch Bestrahlung vernetztem Hartpolyäthylen hergestellt werden. Selbstverständlich können die Stützringe auch aus Metall hergestellt werden. Diese besitzen den Vorteil der geringen Wandstärke. Sie sind jedoch gegenüber Korrosion weniger beständig.
Welded connection between two plastic pipes
The present invention relates to a welded joint between two plastic pipes, for example made of polyethylene.
So far it has been customary to connect polyethylene pipes and sleeves or fittings made of the same material by using a heater to bring the pipe end on the outside and the fitting socket on the inside to welding temperature in order to be subsequently pushed into one another. In the case of thin-walled pipes, the above operation not only softens the surfaces of the pipe ends, but the entire wall. As a result, the pipe ends have too little strength and rigidity and collapse when pushed into the socket ends or throw themselves up in waves.
This calls into question the quality of the weld. Very often this also significantly reduces the flow cross-section.
The present invention also enables thin-walled pipes to be welded properly. The characteristic feature of the invention is that a support ring is provided inside the pipe end, the length of which is adapted to the offset bore of the socket and which has a higher softening temperature than the pipe. Polypropylene, polyamide or irradiated hard polyethylene, for example, can be used as the material for the support ring.
The figures show two different embodiments of the pipe connection according to the invention, namely:
Fig. 1 shows the heating of the connection by means of a tubular welding or heating device in section,
2 shows a type of pipe connection in section,
3 shows a further type of pipe connection in section.
As an example of a welding device, FIG. 1 shows an offset steel pipe 1 which is heated slightly above the welding temperature of the plastic.
If the welding device 1 is firmly clamped somewhere, the sleeve 2 and the pipe end 3 can be heated at the same time. So that the pipe end 3 does not collapse or be compressed when it is pushed into the socket in thin-walled pipes, a support ring 4 made of a plastic with a higher softening temperature is used in the pipe end 3. The welding beads 5 and 6 (Fig. 2) arise by themselves, by pushing on soft material.
Another embodiment of the support ring 7 is shown in FIG. The same has a collar 9 on its outer contour 8, which is clamped as a spacer ring between the end wall 10 of the pipe end 3 and the shoulder 11 of the socket 2 when the pipe 3 is pushed into the socket 2. This creates a cavity 13 between the pipe end 3 and the socket 2, which is used to hold the excess material 12 that is inevitably produced during welding.
The axial position of the support ring 7 in the pipe 3 is clearly defined by the collar.
Support rings that are slotted longitudinally or diagonally and are under radial prestress can also be used as further designs.
It is important that the support rings 4, 7 are made of a material which has a higher softening point than the pipe material. The support rings can, for. B. made of polypropylene, polyamide or rigid polyethylene crosslinked by irradiation. Of course, the support rings can also be made of metal. These have the advantage of low wall thickness. However, they are less resistant to corrosion.
Claims (1)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH6488458A CH365587A (en) | 1958-10-10 | 1958-10-10 | Welded connection between two plastic pipes |
FR802395A FR1233305A (en) | 1958-10-10 | 1959-08-07 | Welded joint for plastic pipe |
GB33691/59A GB869437A (en) | 1958-10-10 | 1959-10-05 | Improvements in or relating to welded joints in tubular members of thermo-plastic material |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH6488458A CH365587A (en) | 1958-10-10 | 1958-10-10 | Welded connection between two plastic pipes |
Publications (1)
Publication Number | Publication Date |
---|---|
CH365587A true CH365587A (en) | 1962-11-15 |
Family
ID=4525962
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CH6488458A CH365587A (en) | 1958-10-10 | 1958-10-10 | Welded connection between two plastic pipes |
Country Status (3)
Country | Link |
---|---|
CH (1) | CH365587A (en) |
FR (1) | FR1233305A (en) |
GB (1) | GB869437A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4221263A (en) * | 1978-04-06 | 1980-09-09 | Nooter Corporation | Tube-type vessel and method of joining the tubes to the tubesheets in such vessels |
DE3926662A1 (en) * | 1989-08-11 | 1991-02-14 | Pvg Patentverwertung | Welding together polypropylene pipes - by using inner sleeve with centre outer rib, heating this and one pipe, pressing pipe over sleeve, cooling , and repeating with second pipe |
DE10340843A1 (en) * | 2003-09-04 | 2005-04-07 | Fränkische Rohrwerke Gebr. Kirchner GmbH + Co. KG | Butt welding of tubes with different wall thicknesses involves insertion of a support under a radial rib at the end of one tube before welding |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1572100A (en) * | 1977-06-10 | 1980-07-23 | Hepworth Iron Co Ltd | Plastics pipe couplings |
ATE122133T1 (en) * | 1989-03-31 | 1995-05-15 | Geberit Ag | WELD SLEEVE. |
NL2005306C2 (en) * | 2010-09-02 | 2012-03-05 | Tersia Nederland B V | CONNECTOR FOR MULTI-LAYER PIPES, WELDING DEVICE FOR CONNECTING THE CONNECTOR TO MULTI-LAYER PIPES, METHOD OF CONNECTING AND A COMPOSITION OBTAINED VIA THE METHOD. |
NL2010686C2 (en) * | 2013-04-22 | 2014-10-23 | Tersia Nederland B V | REINFORCEMENT HOLDER FOR A COUPLER, COMPOSITION OF A REINFORCEMENT HOLDER AND A COUPLER, METHOD FOR WELDING A MULTI-LAYER PIPE WITH THE COMPOSITION. |
-
1958
- 1958-10-10 CH CH6488458A patent/CH365587A/en unknown
-
1959
- 1959-08-07 FR FR802395A patent/FR1233305A/en not_active Expired
- 1959-10-05 GB GB33691/59A patent/GB869437A/en not_active Expired
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4221263A (en) * | 1978-04-06 | 1980-09-09 | Nooter Corporation | Tube-type vessel and method of joining the tubes to the tubesheets in such vessels |
DE3926662A1 (en) * | 1989-08-11 | 1991-02-14 | Pvg Patentverwertung | Welding together polypropylene pipes - by using inner sleeve with centre outer rib, heating this and one pipe, pressing pipe over sleeve, cooling , and repeating with second pipe |
DE10340843A1 (en) * | 2003-09-04 | 2005-04-07 | Fränkische Rohrwerke Gebr. Kirchner GmbH + Co. KG | Butt welding of tubes with different wall thicknesses involves insertion of a support under a radial rib at the end of one tube before welding |
DE10340843B4 (en) * | 2003-09-04 | 2006-01-26 | Fränkische Rohrwerke Gebr. Kirchner GmbH + Co. KG | Method for the end-side welding of two tubular bodies of different wall thickness |
Also Published As
Publication number | Publication date |
---|---|
FR1233305A (en) | 1960-10-12 |
GB869437A (en) | 1961-05-31 |
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