CH532744A - Shrunk sleeve tube connection - esp of polyolefin with underlying adhesive layer - Google Patents
Shrunk sleeve tube connection - esp of polyolefin with underlying adhesive layerInfo
- Publication number
- CH532744A CH532744A CH1917071A CH1917071A CH532744A CH 532744 A CH532744 A CH 532744A CH 1917071 A CH1917071 A CH 1917071A CH 1917071 A CH1917071 A CH 1917071A CH 532744 A CH532744 A CH 532744A
- Authority
- CH
- Switzerland
- Prior art keywords
- connection
- pipes
- adhesive
- pipe
- connecting sleeve
- Prior art date
Links
Classifications
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- 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
- B29C66/11—Joint cross-sections comprising a single joint-segment, i.e. one of the parts to be joined comprising a single joint-segment in the joint cross-section
- B29C66/112—Single lapped joints
- B29C66/1122—Single lap to lap joints, i.e. overlap joints
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- 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
- B29C65/48—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using adhesives, i.e. using supplementary joining material; solvent bonding
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- 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
- B29C65/66—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by liberation of internal stresses, e.g. shrinking of one of the parts to be joined
- B29C65/68—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by liberation of internal stresses, e.g. shrinking of one of the parts to be joined using auxiliary shrinkable elements
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- 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
- B29C66/11—Joint cross-sections comprising a single joint-segment, i.e. one of the parts to be joined comprising a single joint-segment in the joint cross-section
- B29C66/114—Single butt joints
- B29C66/1142—Single butt to butt joints
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- 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
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- 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
- B29C66/5223—Joining tubular articles for forming corner connections or elbows, e.g. for making V-shaped pieces
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- 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
- B29C66/5229—Joining tubular articles involving the use of a socket
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- 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
- B29C66/5229—Joining tubular articles involving the use of a socket
- B29C66/52291—Joining tubular articles involving the use of a socket said socket comprising a stop
- B29C66/52292—Joining tubular articles involving the use of a socket said socket comprising a stop said stop being internal
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- 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
- B29C66/53—Joining single elements to tubular articles, hollow articles or bars
- B29C66/534—Joining single elements to open ends of tubular or hollow articles or to the ends of bars
- B29C66/5344—Joining single elements to open ends of tubular or hollow articles or to the ends of bars said single elements being substantially annular, i.e. of finite length, e.g. joining flanges to tube ends
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- 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
- B29C66/53—Joining single elements to tubular articles, hollow articles or bars
- B29C66/534—Joining single elements to open ends of tubular or hollow articles or to the ends of bars
- B29C66/5346—Joining single elements to open ends of tubular or hollow articles or to the ends of bars said single elements being substantially flat
- B29C66/53465—Joining single elements to open ends of tubular or hollow articles or to the ends of bars said single elements being substantially flat said single flat elements being provided with holes facing the tube ends, e.g. for making heat-exchangers
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- 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
- F16L47/02—Welded joints; Adhesive joints
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- 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
- F16L47/20—Connecting arrangements or other fittings specially adapted to be made of plastics or to be used with pipes made of plastics based principally on specific properties of plastics
- F16L47/22—Connecting arrangements or other fittings specially adapted to be made of plastics or to be used with pipes made of plastics based principally on specific properties of plastics using shrink-down material
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
- F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
- F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
- F28D1/047—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being bent, e.g. in a serpentine or zig-zag
- F28D1/0477—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being bent, e.g. in a serpentine or zig-zag the conduits being bent in a serpentine or zig-zag
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
- F28D7/08—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being otherwise bent, e.g. in a serpentine or zig-zag
- F28D7/082—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being otherwise bent, e.g. in a serpentine or zig-zag with serpentine or zig-zag configuration
- F28D7/085—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being otherwise bent, e.g. in a serpentine or zig-zag with serpentine or zig-zag configuration in the form of parallel conduits coupled by bent portions
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- 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
- F28F21/067—Details
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- 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
- F28F21/08—Constructions of heat-exchange apparatus characterised by the selection of particular materials of metal
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- 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
- F28F9/26—Arrangements for connecting different sections of heat-exchange elements, e.g. of radiators
- F28F9/262—Arrangements for connecting different sections of heat-exchange elements, e.g. of radiators for radiators
- F28F9/264—Arrangements for connecting different sections of heat-exchange elements, e.g. of radiators for radiators by sleeves, nipples
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- 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
- B29C65/48—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using adhesives, i.e. using supplementary joining material; solvent bonding
- B29C65/4805—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using adhesives, i.e. using supplementary joining material; solvent bonding characterised by the type of adhesives
- B29C65/483—Reactive adhesives, e.g. chemically curing adhesives
- B29C65/4835—Heat curing adhesives
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- 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
- B29C65/48—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using adhesives, i.e. using supplementary joining material; solvent bonding
- B29C65/4805—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using adhesives, i.e. using supplementary joining material; solvent bonding characterised by the type of adhesives
- B29C65/483—Reactive adhesives, e.g. chemically curing adhesives
- B29C65/485—Multi-component adhesives, i.e. chemically curing as a result of the mixing of said multi-components
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2705/00—Use of metals, their alloys or their compounds, for preformed parts, e.g. for inserts
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F2275/00—Fastening; Joining
- F28F2275/02—Fastening; Joining by using bonding materials; by embedding elements in particular materials
- F28F2275/025—Fastening; Joining by using bonding materials; by embedding elements in particular materials by using adhesives
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F2275/00—Fastening; Joining
- F28F2275/12—Fastening; Joining by methods involving deformation of the elements
- F28F2275/127—Fastening; Joining by methods involving deformation of the elements by shrinking
Abstract
A sealing connection, for liquid or gas, between tubes oriented in any relationship consists of a shrinkable plastics sleeve. At least the ends of this sleeve (esp. for a bent or branched connection) or the entire length (esp. for a straight butt-joint connection) are shrunk on to the tubes with an underlying layer of ahdesive. A prefd. tube material is cross-linked polyolefin. Adhesive may be e.g. copolymers of ethylene and vinyl acetate, acrylic acid, and/or acrylic acid ester, epoxy or modified phenolic resins.
Description
Flüssigkeits- und gasdichte Verbindung zwischen zwei Rohren und Verfahren zu ihrer Herstellung
Der vorliegenden Erfindung liegt die Aufgabe zu Grunde, eine flüssigkeits- und gasdichte Verbindung zwischen zwei beliebig verlaufenden Rohren zu schaffen, wobei die Verbindung im Temperaturbereich von - lOOOC bis + 100ob und bei Unter- oder berdruck anwendbar sein soll. Solche Verbindungen werden z.B. in den verschiedensten Rohrkühlsystemen verlangt.
Es sind sogenannte Schrumprohre aus diversen Thermoplasten bekannt, die zur Ummantelung von Walzen, Wellen oder Kabelverbindungen, zur Sicherung von Schraubenverbindungen zweier Rohre oder als Verbindungselement zweier stirnseitig aneinanderstossender Rohre oder Wellen dienen. Diese Schrumpfrohre werden unter Erwärmung auf einen grösseren Durchmesser gebracht, so dass sie über den zu überziehenden bzw. die zu verbindenen Gegenstände gezogen werden können. Durch Wiedererwärmung nehmen sie dann ihre frühere Form wieder an und schrumpfen dabei auf die Gegenstände auf.
Die erwähnten Schrumpfrohre eigenen sich nicht für alle Anwendungszwecke. So ist die Haftfestigkeit in vielen Fällen ungenügend wie auch die Dichtigkeit der Verbindungen; die Verbindungen sind in Systemen mit leichtflüchtigen Flüssigkei- ten und mit Gasen nicht brauchbar.
Die Erfindung betrifft eine flüssigkeits- und gasdichte Verbindung von zwei Rohren mit beliebig verlaufenden Achsen unter Verwendung einer Verbindungsmuffe aus schrumpfbarem Kunststoff sowie ein Verfahren zur Herstellung der Verbindung. Sie ist dadurch gekennzeichnet, dass mindestens die Enden der Verbindungsmuffe unter Zwischenlage eines Klebstoffes auf die Enden der zu verbindenden Rohre aufgeschrumpft sind. Das Verfahren zur Herstellung der Verbindung ist dadurch gekennzeichnet, dass mindestens die Enden der Verbindungsmuffe in der Wärme aufgeweitet, dann abgekühlt und unter Zwischenlage eines Klebstoffes auf die Enden der zu verbindenden Rohre aufgesteckt und durch Wärmebehandlung aufgeschrumpft werden, wobei gegebenenfalls die Wärmebehandlung auch zur Aushärtung des Klebstoffes dient.
Besonders geeignet sind schrumpfbare Verbindungsmuffen aus vernetztem Polyolefin. Diese Rohre weisen ein für Thermoplaste optimales Zeitstandverhalten auch bei höheren Temperaturen auf, eine gute Dämpfung bei Schlag und Stossbeanspruchungen, hohe Schlagzähigkeit und Kerbschlagzähigkeit auch bei tiefen Temperaturen sowie geringe Kerbempfindlichkeit. Durch die Schrumpfspannung ist eine gleichmässige Verteilung des Klebstoffes und damit eine garantiert regelmässige Flächenhaftung zwischen dem zu verbindenden Rohrende und dem Schrumpfteil der Verbindungsmuffe unter dauernder Spannung gewährleistet.
Unter vernetztem Polyolefin versteht man ein Polyolefin, dessen Molekülketten durch Brücken miteinander verbunden sind. Diese Brücken reduzieren die Beweglichkeit der Molekülketten, so dass ein Gegenstand aus dem Polyolefin durch Erwärmung in eine andere Form gebracht werden kann, in der er nach Abkühlung fixiert bleibt, von der er jedoch bei Wiedererwärmung in die ursprüngliche Form zurückgeht (Memory-Effekt).
Die Verbindungsmuffen können verschiedene Formen aufweisen wie z.B. gerade Muffen für die stirnseitige Verbindung von Rohren oder auch Abzweigmuffen. Besonders geeignet ist die Erfindung für die Verbindung von parallel verlaufenden Rohren in Kühlsystemen mittels gebogener Verbindungsmuffen. Die zu verbindenden Rohre können aus beliebigen Materialien bestehen, vor allem aus Metall wie z.B. Aluminium, Kupfer, Messing, Stahl, Titan.
Als Klebstoff zum Verbinden der Muffen mit Metallrohren eignen sich z.B. Copolymere des Äthylens mit Vinylacetat, Acrylsäure und/oder Acrylsäureester, sowie Epoxid- und modifizierte Phenolharze. Sie können als Flüssigkeit, Lösung oder Pulver durch Tauchen und Spritzen, durch Umwickeln mit Klebefolien, durch elektrophoretischen Auftrag oder andere Verfahren aufgebracht werden, und zwar sowohl auf die zu verbindenden Rohrenden als auch auf die Innenseite der Verbindungsmuffe. Die zu verbindenden Rohrenden können nach üblichen Verfahren (Entfetten, Ätzen usw. für die Klebeverbindung vorbereitet werden.
Der Schrumpfprozess für Polyolefinmuffen benötigt je nach Werkstoff eine Mindesttemperatur zwischen 80 und 190ob.
Das Aushärten des Klebstoffes kann noch höhere Temperaturen erfordern. Der Schrumpf- und der Aushärteprozess sind bezüglich Temperatur und Zeit sinnvoll aufeinander abzustimmen.
Je nach Beanspruchungsart sind für Rohre im Durchmesserbereich von 9 bis 120 mm die ursprünglichen Innendurchmesser der Verbindungsmuffen 1 bis 10 mm kleiner zu wählen als der Aussendurchmesser der zu verbindenden Rohre, so dass sich die Verbindungsmuffen unter Spannung auf die Rohre aufschrumpfen.
Die Erfindung ist überall dort vorteilhaft, wo wegen schwerer Zugänglichkeit oder aus technischen Gründen ein Verbinden von Rohren durch Schweissen. Löten Verschrauben, Klemmen usw. nicht möglich oder nicht wirtschaftlich ist. Als Beispiel kommen die Verbindungen von Aluminium-Rohren bei Wärmeaustauschern, wo die Reinigung gelöteter Rohrverbindungen sehr aufwendig ist. oder Reparaturarbeiten an Haus-Wasserleitungen in Frage. Die Erfindung ermöglicht auch die Verbindung von Rohren aus verschiedenen Metallen miteinander die bei direktem Kontak korrosionsgefährdet sind. Auch werden sogenannte wilde, Korrosionen verursachende Ströme isoliert.
Die Fig. 1-3 zeigen Querschnitte durch Rohrverbindungen gemäss der Erfindung und Fig. 4 ein Anwendungsbeispiel. Die Fig. 1 zeigt die gerade Verbindung zweier zusammenstossender Rohre 1 und 2 mit aufgebrachter Klebstoffschicht 3 und der aufgeschobenen. über ihre ganze Länge aufgeweiteten Verbindungsmuffe 4 vor dem Aufschrumpfen. Fig. 2 zeigt die fertige Verbindung. In Fig. 3 ist eine bogenförmige Verbindungsmuffe 5 dargestellt zur Verbindung zweier paralleler Rohre 1 und 2. Es wurden lediglich die Enden des Rohrbogens aufgeweitet. Das Ende 6 ist im aufgeweiteten Zustand gezeigt; das Ende 7 ist bereits aufgeschrumpft (die Klebstoffschicht ist nicht dargestellt). Die Fig. 4 zeigt einen Ausschnitt aus einem Wärmeaustauscher mit den parallelen Rohren 8 und den Kühllamellen 9. Die Rohrenden sind durch Umlenkbogen 10 gemäss Fig. 3 miteinander verbunden.
Die den Ein- und Austritt des Systems bildenden Rohrenden 11 sind durch gerade Verbindungsmuffen 12 mit Anschlussmuffen 13 verbunden.
Beispiel I
Zwei stumpf aneinanderstossende Aluminium-Rohre mit einem Aussenquerschnitt von 18 mm wurden entfettet, schwach gebeizt und in einem Fall mit einer 0,1 mm starken Klebstoftolie umwickelt und mit einer Verbindungsmuffe von 36 mm Länge aus vernetztem Polyäthylen hoher Dichte über zogen. die vom Ausgangsquerschnitt von 16/20 mm auf 20/ 25 mm aufgeweitet wurde. Zum Aufschrumpfen wurde die Verbindung während 10 Minuten auf 140-150OC erwärmt, wobei auch der Klebefilm schmolz und nach dem Abkühlen eine innige Verbindung zwischen Aluminium und Polyäthylen ergab.
Die Klebefolie bestand aus handelsüblichen Produkten, einem Äthylen-Acrylsäure-Colopymerisat (A) und einem Äthylenpfropfpolymerisat (B).
Die erhaltene Rohrverbindung wurde bei verschiedenen Temperaturen auf Druck geprüft; es ergaben sich bis zum l'ndichtwerden der Verbindung folgende Werte: Prúftemlleratur: Klebstoff A Klebstoff B OC 763 atü 100 atü 20cC 320 atü 285 atü 50 C 620 atü 430 atü 100#C 40 atü 38 atü
Im Vergleich dazu war ohne Verwendung von Klebstoff bei 'O C die Verbindung bereits bei 12 atü undicht.
Beispiel 2
Bei einem Wärmeaustauscher gemäss Fig. 4 mit Aluminium-Rohren vom Querschnitt 16 x 1 mm wurden Umlenkbogen und Anschlussmuffen aus vernetztem Polyäthylen hoher Dichte verwendet. Bei den Bogen waren nur 16 mm der Rohrbogenenden derart aufgeweitet, dass wie bei den geraden Anschlussmuffen nach dem Schrumpfprozess eine Massdifferenz von 2 mm gegenüber dem ursprünglichen Innendurchmesser in nicht aufgeweitetem Zustand verblieb. Die Rohrenden wurden in eine Lösung des Copolymers von Äthylen mit Vinylacetat getaucht, wobei sich eine Klebstoffschicht von etwa 0,1 Am Dicke bildete.
Aufgeschrumpft wurde in einem Luftumwälzofen bei einer Temperatur von 150'C. Der geforderte Prüfdruck von 12 atü bei 80C wurde erreicht. ohne dass eine Verbindungsstelle eine Undichtheit gezeigt hätte.
Beispiel 3
Bei einem Wasserleitungsrohr wurde ein Stück herausgeschnitten und eine T-förmige Abzweigung eingesetzt. Die Rohrenden und Verbindungsstellen des T-Abz,veigstückes wurden mit Toluol entfettet und mit einem Zweikomponenten Epoxydharz vom Typ G-EP-6 nach VSM-Norm 77200 3 bestrichen. Als Verbindungsstück der stirnseitig an das T Abzweigstück anstossenden Stahlrohre wurde je eine Schrumpfmuffe aus vernetztem Polyäthylen hoher Dichte verwendet. Mit einem tragbaren Nvarmluftgerät wurden die aufgesteckten Muffen auf 140 C erwärmt. Nach '4stündiger Aushärtezeit des Epoxydharz-Klebstoffes bei 'O;C konnte die Verbindung verlustfrei mit 15 atü Wasser abgepresst werden.
PATENTANSPRUCH 1
Flüssigkeits- und gasdichte Verbindung zwischen zwei Rohren mit beliebig verlaufenden Achsen unter Verwendung einer Verbindungsmuffe aus schrumpfbarem Kunststoff. dadurch gekennzeichnet, dass mindestens die Enden der Verbindungsmuffe unter Zwischenlage eines Klebstoffes auf die Enden der zu verbindenden Rohre aufgeschrumpft sind.
PATENTANSPRUCH II
Verfahren zur Herstellung einer flüssigkeits- und gasdichten Verbindung nach Patentanspruch 1 dadurch gekennzeichnet, dass mindestens die Enden der Verbindungsmuffe in der Wärme aufgeweitet, dann abgekühlt und unter Zwischenlage eines Klebstoffes auf die Enden der zu verbindenden Rohre lufgesteckt und durch Wärmebehandlung aufgeschrumpft werden.
PATENTANSPRUCH III
Verwendung der Verbindung nach Patentanspruch I für die Verbindung von Rohren in Wärmeaustauschern.
UNTERANSPRÜCHE
1. Verbindung nach Patentanspruch I, dadurch gekennzeichnet, dass die Verbindungsmuffe über ihre ganze Länge auf zwei zusammenstossende Rohrende aufgeschrumpft ist.
2. Verbindung nach Patentanspruch I, dadurch gekennzeinet, dass die Verbindungsmuffe ein Rohrbogen ist, deren Enden auf di zu verbindenden Rohrenden aufgeschrumpft sind.
3. Verbindung nach Patentanspruch I, dadurch gekennzeichnet, dass die Verbindungsmuffe eine Abzweigung ist, deren Enden auf die zu verbindenden Rohrenden aufgeschrumpft sind.
**WARNUNG** Ende DESC Feld konnte Anfang CLMS uberlappen**.
Liquid and gas-tight connection between two pipes and their method of manufacture
The present invention is based on the object of creating a liquid-tight and gas-tight connection between two arbitrarily extending pipes, the connection being applicable in the temperature range from −100 ° C. to + 100 ° C. and under negative or positive pressure. Such compounds are e.g. required in a wide variety of pipe cooling systems.
So-called shrink pipes made of various thermoplastics are known, which are used to coat rollers, shafts or cable connections, to secure screw connections between two pipes or as a connecting element between two pipes or shafts butting against one another at the end. These shrink tubes are heated to a larger diameter, so that they can be pulled over the objects to be covered or connected. When they are rewarmed, they take on their previous shape and shrink onto the objects.
The shrink tubes mentioned are not suitable for all purposes. In many cases, the adhesive strength is insufficient, as is the tightness of the connections; the compounds cannot be used in systems with volatile liquids and gases.
The invention relates to a liquid-tight and gas-tight connection of two pipes with axes that run in any direction using a connecting sleeve made of shrinkable plastic and a method for producing the connection. It is characterized in that at least the ends of the connecting sleeve are shrunk onto the ends of the pipes to be connected with the interposition of an adhesive. The method for producing the connection is characterized in that at least the ends of the connecting sleeve are expanded in the heat, then cooled and, with the interposition of an adhesive, pushed onto the ends of the pipes to be connected and shrunk on by heat treatment, the heat treatment also being used to harden the Serves adhesive.
Shrinkable connection sleeves made of cross-linked polyolefin are particularly suitable. These pipes have optimum creep behavior for thermoplastics even at higher temperatures, good damping in the event of impact and shock loads, high impact strength and notched impact strength even at low temperatures, and low notch sensitivity. The shrinkage tension ensures an even distribution of the adhesive and thus a guaranteed regular surface adhesion between the pipe end to be connected and the shrink part of the connecting sleeve under constant tension.
Crosslinked polyolefin is understood to mean a polyolefin whose molecular chains are linked to one another by bridges. These bridges reduce the mobility of the molecular chains so that an object made of the polyolefin can be brought into another shape by heating, in which it remains fixed after cooling, but from which it returns to its original shape when it is reheated (memory effect).
The connection sleeves can have various shapes, e.g. straight sleeves for connecting pipes to the front or branch sleeves. The invention is particularly suitable for the connection of parallel pipes in cooling systems by means of curved connecting sleeves. The pipes to be connected can be made of any material, especially metal, e.g. Aluminum, copper, brass, steel, titanium.
Suitable adhesives for connecting the sleeves to metal pipes are e.g. Copolymers of ethylene with vinyl acetate, acrylic acid and / or acrylic acid esters, as well as epoxy and modified phenolic resins. They can be applied as a liquid, solution or powder by dipping and spraying, by wrapping with adhesive film, by electrophoretic application or other methods, both on the pipe ends to be connected and on the inside of the connecting sleeve. The pipe ends to be connected can be prepared for the adhesive connection using conventional methods (degreasing, etching, etc.).
The shrinking process for polyolefin sleeves requires a minimum temperature between 80 and 190ob, depending on the material.
The curing of the adhesive can require even higher temperatures. The shrinking and curing processes should be coordinated with one another in terms of temperature and time.
Depending on the type of stress, for pipes in the diameter range from 9 to 120 mm, the original inside diameter of the connecting sleeves should be selected 1 to 10 mm smaller than the outside diameter of the pipes to be connected so that the connecting sleeves shrink onto the pipes under tension.
The invention is advantageous wherever pipes are connected by welding due to difficult access or technical reasons. Soldering, screwing, clamping, etc. is not possible or not economical. An example are the connections between aluminum pipes in heat exchangers, where the cleaning of soldered pipe connections is very time-consuming. or repair work on house water pipes in question. The invention also enables pipes made of different metals to be connected to one another, which are at risk of corrosion if they come into direct contact. So-called wild currents that cause corrosion are also isolated.
1-3 show cross-sections through pipe connections according to the invention and FIG. 4 shows an example of use. Fig. 1 shows the straight connection of two colliding tubes 1 and 2 with applied adhesive layer 3 and the pushed on. Connection sleeve 4 expanded over its entire length before shrinking. Fig. 2 shows the completed connection. In Fig. 3 an arcuate connecting sleeve 5 is shown for connecting two parallel pipes 1 and 2. Only the ends of the pipe bend have been widened. The end 6 is shown in the expanded state; the end 7 has already been shrunk on (the adhesive layer is not shown). FIG. 4 shows a section from a heat exchanger with the parallel tubes 8 and the cooling fins 9. The tube ends are connected to one another by deflection bends 10 according to FIG.
The pipe ends 11 forming the inlet and outlet of the system are connected to connecting sleeves 13 by straight connecting sleeves 12.
Example I.
Two butt butted aluminum tubes with an external cross-section of 18 mm were degreased, lightly stained and in one case wrapped with a 0.1 mm thick adhesive film and covered with a connecting sleeve 36 mm long made of cross-linked high-density polyethylene. which was expanded from the initial cross-section of 16/20 mm to 20/25 mm. To shrink it on, the connection was heated to 140-150 ° C for 10 minutes, during which the adhesive film also melted and, after cooling, resulted in an intimate connection between aluminum and polyethylene.
The adhesive film consisted of commercial products, an ethylene-acrylic acid copolymer (A) and an ethylene graft polymer (B).
The pipe joint obtained was tested for pressure at various temperatures; The following values were obtained until the connection was sealed: Test temperature: Adhesive A Adhesive B OC 763 at 100 at 20 cC 320 at 285 at 50 C 620 at 430 at 100 # C 40 at 38 at
In comparison, without the use of glue, at 'O C the connection was already leaking at 12 atmospheres.
Example 2
In the case of a heat exchanger according to FIG. 4 with aluminum tubes with a cross section of 16 × 1 mm, deflection bends and connecting sleeves made of crosslinked high-density polyethylene were used. In the case of the bends, only 16 mm of the pipe bend ends were widened in such a way that, as with the straight connection sleeves, after the shrinking process, a dimensional difference of 2 mm compared to the original inner diameter remained in the unexpanded state. The pipe ends were immersed in a solution of the copolymer of ethylene with vinyl acetate, forming an adhesive layer about 0.1 µm thick.
It was shrunk on in an air circulation oven at a temperature of 150.degree. The required test pressure of 12 atmospheres at 80C was achieved. without a connection point showing a leak.
Example 3
A piece of a water pipe was cut out and a T-shaped branch was inserted. The pipe ends and connection points of the T-Abz, twisting piece were degreased with toluene and coated with a two-component epoxy resin of type G-EP-6 according to VSM standard 77200 3. A shrink sleeve made of cross-linked high-density polyethylene was used as the connecting piece for the steel pipes abutting the T branch piece. The attached sleeves were heated to 140 ° C. with a portable hot air device. After the epoxy resin adhesive had cured for 4 hours at 0; C, the connection could be pressed with 15 atm water without any loss.
PATENT CLAIM 1
Liquid- and gas-tight connection between two pipes with any axis using a connecting sleeve made of shrinkable plastic. characterized in that at least the ends of the connecting sleeve are shrunk onto the ends of the pipes to be connected with the interposition of an adhesive.
PATENT CLAIM II
Method for producing a liquid-tight and gas-tight connection according to claim 1, characterized in that at least the ends of the connecting sleeve are expanded in the heat, then cooled and, with the interposition of an adhesive, placed in air on the ends of the pipes to be connected and shrunk by heat treatment.
PATENT CLAIM III
Use of the connection according to claim I for connecting pipes in heat exchangers.
SUBCLAIMS
1. Connection according to patent claim I, characterized in that the connecting sleeve is shrunk over its entire length onto two pipe ends that come together.
2. Connection according to claim I, characterized in that the connecting sleeve is a pipe bend, the ends of which are shrunk onto the pipe ends to be connected.
3. Connection according to claim I, characterized in that the connecting sleeve is a junction whose ends are shrunk onto the pipe ends to be connected.
** WARNING ** End of DESC field could overlap beginning of CLMS **.
Claims (1)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1917071A CH532744A (en) | 1971-12-30 | 1971-12-30 | Shrunk sleeve tube connection - esp of polyolefin with underlying adhesive layer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1917071A CH532744A (en) | 1971-12-30 | 1971-12-30 | Shrunk sleeve tube connection - esp of polyolefin with underlying adhesive layer |
Publications (1)
Publication Number | Publication Date |
---|---|
CH532744A true CH532744A (en) | 1973-01-15 |
Family
ID=4437784
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CH1917071A CH532744A (en) | 1971-12-30 | 1971-12-30 | Shrunk sleeve tube connection - esp of polyolefin with underlying adhesive layer |
Country Status (1)
Country | Link |
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CH (1) | CH532744A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0102919A2 (en) * | 1982-08-30 | 1984-03-14 | HUBER & SUHNER AG KABEL-, KAUTSCHUK-, KUNSTSTOFF-WERKE | Method of connecting tubes, and connection manufactured according thereto |
EP0264178A2 (en) * | 1986-08-21 | 1988-04-20 | The Croydex Company Limited | Assembly of tap connectors to hoses |
US5735554A (en) * | 1991-08-31 | 1998-04-07 | Imgam; Fredrich | Tube conduit connection and method of producing the same from polyolefins |
DE10114300C1 (en) * | 2001-03-23 | 2002-10-31 | Uponor Innovation Ab | Fitting for connecting plastic pipes to e.g. heat exchangers comprises metal pipe sections on which sleeves with profiled outer surface are fitted, ends of pipe being slid over these |
-
1971
- 1971-12-30 CH CH1917071A patent/CH532744A/en not_active IP Right Cessation
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0102919A2 (en) * | 1982-08-30 | 1984-03-14 | HUBER & SUHNER AG KABEL-, KAUTSCHUK-, KUNSTSTOFF-WERKE | Method of connecting tubes, and connection manufactured according thereto |
EP0102919A3 (en) * | 1982-08-30 | 1985-05-22 | HUBER & SUHNER AG KABEL-, KAUTSCHUK-, KUNSTSTOFF-WERKE | Method of connecting tubes, and connection manufactured according thereto |
EP0264178A2 (en) * | 1986-08-21 | 1988-04-20 | The Croydex Company Limited | Assembly of tap connectors to hoses |
EP0264178A3 (en) * | 1986-08-21 | 1988-04-27 | The Croydex Company Limited | Assembly of tap connectors to hoses |
US5735554A (en) * | 1991-08-31 | 1998-04-07 | Imgam; Fredrich | Tube conduit connection and method of producing the same from polyolefins |
DE10114300C1 (en) * | 2001-03-23 | 2002-10-31 | Uponor Innovation Ab | Fitting for connecting plastic pipes to e.g. heat exchangers comprises metal pipe sections on which sleeves with profiled outer surface are fitted, ends of pipe being slid over these |
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