GB2445796A - Jointing Of Thermoplastic Spirally Wound Hollow Section Pipes - Google Patents

Jointing Of Thermoplastic Spirally Wound Hollow Section Pipes Download PDF

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Publication number
GB2445796A
GB2445796A GB0701005A GB0701005A GB2445796A GB 2445796 A GB2445796 A GB 2445796A GB 0701005 A GB0701005 A GB 0701005A GB 0701005 A GB0701005 A GB 0701005A GB 2445796 A GB2445796 A GB 2445796A
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GB
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Patent type
Prior art keywords
pipe
thermoplastic
pipes
sleeve
spirally wound
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB0701005A
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GB0701005D0 (en )
Inventor
Eric Bridgstock
Original Assignee
Eric Bridgstock
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/34Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement"
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/34Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement"
    • B29C65/3404Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the type of heated elements which remain in the joint
    • B29C65/342Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the type of heated elements which remain in the joint comprising at least a single wire, e.g. in the form of a winding
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/48Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using adhesives, i.e. using supplementary joining material; solvent bonding
    • B29C65/4805Joining 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
    • B29C65/481Non-reactive adhesives, e.g. physically hardening adhesives
    • B29C65/4815Hot melt adhesives, e.g. thermoplastic adhesives
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00General aspects of processes or apparatus for joining preformed parts
    • B29C66/01General aspects dealing with the joint area or with the area to be joined
    • B29C66/05Particular design of joint configurations
    • B29C66/10Particular design of joint configurations particular design of the joint cross-sections
    • B29C66/11Joint 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
    • B29C66/114Single butt joints
    • B29C66/1142Single butt to butt joints
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00General aspects of processes or apparatus for joining preformed parts
    • B29C66/50General 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
    • B29C66/51Joining 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
    • B29C66/52Joining tubular articles, bars or profiled elements
    • B29C66/522Joining tubular articles
    • B29C66/5221Joining tubular articles for forming coaxial connections, i.e. the tubular articles to be joined forming a zero angle relative to each other
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L47/00Connecting arrangements or other fittings specially adapted to be made of plastics or to be used with pipes made of plastics
    • F16L47/02Welded joints; Adhesive joints
    • F16L47/03Welded joints with an electrical resistance incorporated in the joint
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C53/00Shaping by bending, folding, twisting, straightening or flattening; Apparatus therefor
    • B29C53/56Winding and joining, e.g. winding spirally
    • B29C53/58Winding and joining, e.g. winding spirally helically
    • B29C53/78Winding and joining, e.g. winding spirally helically using profiled sheets or strips
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/34Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement"
    • B29C65/3404Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the type of heated elements which remain in the joint
    • B29C65/342Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the type of heated elements which remain in the joint comprising at least a single wire, e.g. in the form of a winding
    • B29C65/3424Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the type of heated elements which remain in the joint comprising at least a single wire, e.g. in the form of a winding said at least a single wire having the form of a coil spring
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/34Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement"
    • B29C65/3468Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the means for supplying heat to said heated elements which remain in the join, e.g. special electrical connectors of windings
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/34Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement"
    • B29C65/3472Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the composition of the heated elements which remain in the joint
    • B29C65/3476Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the composition of the heated elements which remain in the joint being metallic
    • B29C65/348Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" characterised by the composition of the heated elements which remain in the joint being metallic with a polymer coating
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/78Means for handling the parts to be joined, e.g. for making containers or hollow articles, e.g. means for handling sheets, plates, web-like materials, tubular articles, hollow articles or elements to be joined therewith; Means for discharging the joined articles from the joining apparatus
    • B29C65/7841Holding or clamping means for handling purposes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00General aspects of processes or apparatus for joining preformed parts
    • B29C66/70General 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
    • B29C66/71General 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
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29KINDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS
    • B29K2023/00Use of polyalkenes or derivatives thereof as moulding material
    • B29K2023/04Polymers of ethylene
    • B29K2023/06PE, i.e. polyethylene
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29KINDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS
    • B29K2101/00Use of unspecified macromolecular compounds as moulding material
    • B29K2101/12Thermoplastic materials
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29LINDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2023/00Tubular articles
    • B29L2023/22Tubes or pipes, i.e. rigid
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29LINDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2024/00Articles with hollow walls

Abstract

A method of modifying an end face region of a spirally wound hollow section thermoplastic pipe (fig. 1), the method comprises: welding an attachment (fig.2d) to the end face region of the pipe, the attachment is formed from an extruded channel cross-section 2a formed into a circle 2b with the closed region of said channel being welded to the end face region of said pipe, thus forming a female coupling for receiving a jointing sleeve fig.5. The jointing sleeve is formed from an extruded rectangular box section formed into a circle matching the circumference of the pipe to which it is to be attached. The sleeve having electrically conductive resistance wire wound spirally around it. Preferably clamps (fig. 6) are used to hold the pipe joint together during the electric welding process.

Description

JOINTING OF THERMOPLASTIC SPIRALLY WOUND HOLLOW SECTION PIPES

DESCRIPTION 2445796

Hollow section spirally wound thermoplastic pipes [rig 1 a,b,c] are well established and widely used.

They provide a means of using the excellent properties of polyethylene pipe without the necessity of producing a solid wall which would be uneconomic and unnecessarily heavy especially for large diameters. The only disadvantage of these hollow section pipes is the difficulty of joining them, especially by the favoured heat fusion methods. When cut at right angles to their axis these pipes present an uneven area at their ends which is not suitable for fusion.

To overcome this problem the present invention proposes the following methods and inventions:-The spirally wound thermoplastic pipes are fitted with modified ends [fig 2d], designed to accommodate an electrically heated thermoplastic jointing sleeve [fig 3d] which can be manufactured by the same method used to produce the extruded hollow sections of the pipe itself.

The modification of the pipe ends in ideally carried out during the manufacturing process. An open-ended rectangular section extrusion [fig 2a] is manufactured, similar to the closed section extrusion used to form the spirally wound pipe. The extrusion is then cut to length and the long side wound around a cylindrical former to create a circular shape [fig 2b] of similar dimensions to the pipe itself. It is then welded at the ends [fig 2c] to form a closed ring. These rings are then welded to the ends of each length of pipe [fig 2d] with the open ends at the leading edge.

The internal dimension of the socket formed by the modification of the pipe end is such that a jointing sleeve [fig 3d] will fit closely inside it, the electrical heating wires making contact with the socket as in fig 4.

The jointing sleeve [fig 3d] is formed from an extruded closed rectangular section [fig 3a] which is subsequently cut to length and formed into a circle [fig 3b], for example around a metal cylinder, and then welded at its ends [fig 3d to form a closed ring. Electrically conductive resistance wire, preferably coated with polyethylene, is wound spirally around the rectangular section and terminated on the outside surface midway between the ends of the section [fig 3d]. The wire may be wound as shown in fig 5 in order to reduce the resistance of the coil and hence the fusion time.

It may also be lacquered to reduce the consequences of wire to wire contact. The jointing sleeve [fig 3d] may be grooved in order to retain the electrical wire or the wire may be welded to the sleeve at intervals around its circumference.

Jointing of these modified pipes is achieved by inserting the jointing sleeve into adjacent pipes and sliding each pipe fully over the ring so that the jointing sleeve is completely covered [fig 4], leaving the wire ends exposed for connection to a suitable electrical power source. The passage of current through the wires softens the polyethylene surfaces and causes them to fuse.

Internal and external mechanical clamps [fig 6] may be used to provide radial forces capable of holding the abutting surfaces in contact during the heating and cooling process.

The heating ring is particularly advantageous because it provides the means of fusing the pipes and also facilitates a positive method of aligning the two pipes to be jointed without reducing the strength of the joint area.

Claims (1)

  1. JOINTING OF THERMOPLASTIC SPIRALLY WOUND HOLLOW SECTION PIPES
    (i) A method of modifying the ends of spirally wound hollow section thermoplastic pipes [fig 1) by the welded attachment of an open sided rectangular thermoplastic extrusion formed into a circular shape and closed at the ends by welding [fig 2]. The modification has the effect of providing a regular socketted termination at the end of each spirally wound pipe [fig 2d].
    (ii) A welding sleeve fabricated from a rectangular section thermoplastic extrusion [fig 3d] wound spirally with electrical resistance wire where the sleeve engages with sockets at the pipe ends [fig 4).
    (iii) A welding sleeve as described in (ii) whose length is such that when entered into the sockets provided at the pipe ends provides significant self alignment of the adjoining pipes.
    (iv) A welding sleeve as described in (ii) that when entered into the sockets described in (i) and electrically heated, facilitates the thermal fusion of adjoining pipes.
    (v) A welding sleeve as described in (ii) (iii) (iv) that may be secured during thermal fusion and during cooling by clamps capable of applying radial forces to the joint interfaces [fig 6].
GB0701005A 2007-01-19 2007-01-19 Jointing of thermoplastic spirally wound hollow section pipes Withdrawn GB0701005D0 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB0701005A GB0701005D0 (en) 2007-01-19 2007-01-19 Jointing of thermoplastic spirally wound hollow section pipes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0701005A GB0701005D0 (en) 2007-01-19 2007-01-19 Jointing of thermoplastic spirally wound hollow section pipes

Publications (2)

Publication Number Publication Date
GB0701005D0 GB0701005D0 (en) 2007-02-28
GB2445796A true true GB2445796A (en) 2008-07-23

Family

ID=37846605

Family Applications (1)

Application Number Title Priority Date Filing Date
GB0701005A Withdrawn GB0701005D0 (en) 2007-01-19 2007-01-19 Jointing of thermoplastic spirally wound hollow section pipes

Country Status (1)

Country Link
GB (1) GB0701005D0 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5320697A (en) * 1991-09-07 1994-06-14 Wilhelm Hegler Method for welding together pipes consisting of thermoplastic plastics
WO2000061978A1 (en) * 1999-04-09 2000-10-19 Oy Kwh Pipe Ab Preparation of an end of a thermoplastics tube manufactured by spirally winding a hollow profile
EP1201403A2 (en) * 2000-10-31 2002-05-02 David Michael Anthony Kenworthy Electrofusible units
US6521072B1 (en) * 1996-05-28 2003-02-18 C&S Intellectual Properties, Llc Method of coupling profile wall thermoplastic pipes
WO2007006865A1 (en) * 2005-07-08 2007-01-18 Oy Kwh Pipe Ab Method and device for joining pipes

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5320697A (en) * 1991-09-07 1994-06-14 Wilhelm Hegler Method for welding together pipes consisting of thermoplastic plastics
US6521072B1 (en) * 1996-05-28 2003-02-18 C&S Intellectual Properties, Llc Method of coupling profile wall thermoplastic pipes
WO2000061978A1 (en) * 1999-04-09 2000-10-19 Oy Kwh Pipe Ab Preparation of an end of a thermoplastics tube manufactured by spirally winding a hollow profile
EP1201403A2 (en) * 2000-10-31 2002-05-02 David Michael Anthony Kenworthy Electrofusible units
WO2007006865A1 (en) * 2005-07-08 2007-01-18 Oy Kwh Pipe Ab Method and device for joining pipes

Also Published As

Publication number Publication date Type
GB0701005D0 (en) 2007-02-28 grant

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WAP Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1)