JPH0439494A - エレクトロフュージョン継手及びその製造方法 - Google Patents

エレクトロフュージョン継手及びその製造方法

Info

Publication number
JPH0439494A
JPH0439494A JP2145223A JP14522390A JPH0439494A JP H0439494 A JPH0439494 A JP H0439494A JP 2145223 A JP2145223 A JP 2145223A JP 14522390 A JP14522390 A JP 14522390A JP H0439494 A JPH0439494 A JP H0439494A
Authority
JP
Japan
Prior art keywords
heating wire
joints
electrofusion
electric heating
joint
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.)
Pending
Application number
JP2145223A
Other languages
English (en)
Inventor
Takayuki Handa
半田　孝幸
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsui Petrochemical Industries Ltd
Original Assignee
Mitsui Petrochemical Industries Ltd
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
Application filed by Mitsui Petrochemical Industries Ltd filed Critical Mitsui Petrochemical Industries Ltd
Priority to JP2145223A priority Critical patent/JPH0439494A/ja
Publication of JPH0439494A publication Critical patent/JPH0439494A/ja
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D23/00—Producing tubular articles
    • B29D23/001—Pipes; Pipe joints
    • B29D23/003—Pipe joints, e.g. straight joints
    • B29D23/005—Pipe joints, e.g. straight joints provided with electrical wiring
    • 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
    • B29C45/14—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor incorporating preformed parts or layers, e.g. injection moulding around inserts or for coating articles
    • B29C45/14549—Coating rod-like, wire-like or belt-like articles
    • 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
    • B29C65/34—Joining 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"
    • 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
    • B29C65/56—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using mechanical means or mechanical connections, e.g. form-fits
    • B29C65/565—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using mechanical means or mechanical connections, e.g. form-fits involving interference fits, e.g. force-fits or press-fits
    • 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
    • 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
    • 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
    • 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
    • B29C66/303—Particular design of joint configurations the joint involving an anchoring effect
    • B29C66/3034—Particular design of joint configurations the joint involving an anchoring effect making use of additional elements, e.g. meshes
    • 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
    • B29C66/51—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
    • 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
    • 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
    • B29C65/34—Joining 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"
    • B29C65/3404—Joining 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
    • B29C65/3444—Joining 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 being a ribbon, band or strip
    • 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
    • B29C65/34—Joining 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"
    • B29C65/3472—Joining 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
    • B29C65/3476—Joining 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/24—Pipe joints or couplings

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Branch Pipes, Bends, And The Like (AREA)
  • Injection Moulding Of Plastics Or The Like (AREA)

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、管同志を連結するソケット継手、エルボ継手
、Ｔ継手、レジユーザ継手或いはキャップ継手などプラ
スチック管による配管工事において使用され、内側に電
熱線をコイル状にして埋設したエレクトロフュージョン
継手及びその製造方法に関する。
従来技術 ポリエチレン等のプラスチック管は、適度な剛性と可撓
性を有し、また金属管に比べ軽くかつ腐食することもな
いなど種々の利点を有することから近年、上下水道やガ
ス管等に多用されるようになっできた。こうしたプラス
千ツク管による配管工事では、ソケット継手、サドル継
手、エルボ継手、Ｔ継手、レジユーザ継手等によって管
を連結したり、管端部にキャップ継手を取着するのに、
管の外周面と継手の内周面とをそれぞれヒータによって
加熱溶融したのち管端部に継手を押込んだり、管外周に
継手を押し当てたりして融着していたが、近年第３図に
示すように、内側に電熱線１を埋設した成形品よりなり
、管との融着を通電により管との接融面を加熱溶融して
行うエレクトロフュージョン継手が開発された。第４図
はソケット継手２と管３とを融着した状態を示すもので
ある。
発明が解決しようとする課題 継手と管を融着するときには、継手内面と管外面とを清
掃して汚れを除去せねばならない。汚れたま＼の状態で
融着すると、融着界面に汚れが層状に介在し、融着強度
が低下して引張荷重が加わったとき管が継手から抜は出
るおそれがある。
しかしながら現場での施工時においては、清掃を怠った
り、清掃が不十分となることも考えられる。
本発明は、例え清掃を怠るようなことがあっても融着強
度が損われるようなことのないエレクトロフュージョン
継手並びにその製造方法を提供することを目的とする。
課題の解決手段及び作用 本発明の継手は、内側に電熱線をコイル状に埋設したソ
ケット継手、エルボ継手、Ｔ継手、レジユーザ継手、キ
ャップ継手等のエレクトロフュージョン継手において、
電熱線に引張応力により伸びを与えた状態で一体成形し
たことを特徴とし、その製造方法は電熱線に引張応力を
与え、伸ばした状態でコアにコイル状に巻付けたのち射
出成形してなるものである。
本発明の継手によれば、電熱線の加熱により周りの樹脂
が溶融されると、引張応力を除去された電熱線は収縮し
てコイル径が縮小し、融着界面を横切る位置に移動する
。
ここで引張応力は通常、弾性伸びが１％以上与えられる
ように加えられる。
本発明の別の継手は、電熱線として加熱したとき収縮す
る形状記憶合金を使用したことを特徴とするもので、加
熱したとき元の形状に戻るべく収縮し、コイル径が縮小
する。電熱線に用いられる形状記憶合金としては通常、
電熱線が２００℃以上に加熱されたとき１％以上の収縮
を来すものが使用される。
実施例 第１図に示すエレクトロフユージョンソケソト継手は、
弾性体よりなる平形状の電ｇｊ！、線５に引張荷重を加
え、１％以上の伸びを与えた状態でコアに一定間隔でコ
イル状に巻付け、射出成形して得られたもので、内側に
平形状の電熱線５が１％以上の弾性伸びを与えられた状
態でコイル状に埋設して一体成形されている。
第２図は融着後の状態を示すもので、引張応力の解消に
より電熱ｖＡ５が収縮し、コイル径が縮小して融着界面
６を横切る位置に移動した状態を示している。
発明の効果 本発明により提供されるエレクトロフュージョン継手は
、融着後電熱線が融着界面を横切るように位置するため
例え融着界面に汚れがあっても管の引張強度は強く、管
が継手から簡単に抜は出るようなことはない。
【図面の簡単な説明】
第１図は本発明に係るエレクトロフユージョンソケント
継手の断面図、第２図は融着後の断面図、第３図は従来
例の断面図、第４図は融着後の同断面図である。 ２・・エレクトロフュージョン継手 ３・・管　５・・電熱線　６・・融着界面出願人　三井
石油化学工業株式会社

Claims (6)

    【特許請求の範囲】
  1. （１）内側に電熱線をコイル状に埋設したソケット継手
    、エルボ継手、Ｔ継手、レジユーザ継手、キャップ継手
    等のエレクトロフュージョン継手において、電熱線に引
    張応力により伸びを与えた状態で一体成形したことを特
    徴とするエレクトロフュージョン継手。
  2. （２）電熱線に引張応力を与え、伸ばした状態でコアに
    コイル状に巻付けたのち射出成形することを特徴とする
    請求項１記載のエレクトロフュージョン継手の製造方法
    。
  3. （３）伸びは１％以上与えられる請求項１記載のエレク
    トロフュージョン継手。
  4. （４）内側に電熱線をコイル状に埋設したソケット継手
    、エルボ継手、Ｔ継手、レジユーザ継手、キャップ継手
    等のエレクトロフュージョン継手において、電熱線とし
    て加熱したとき収縮する形状記憶合金を使用したことを
    特徴とするエレクトロフュージョン継手。
  5. （５）電熱線は、２００℃以上に加熱したとき１％以上
    の収縮を来たす形状記憶合金である請求項４記載のエレ
    クトロフュージョン継手
  6. （６）電熱線は平形状である請求項１記載のエレクトロ
    フュージョン継手。
JP2145223A 1990-06-01 1990-06-01 エレクトロフュージョン継手及びその製造方法 Pending JPH0439494A (ja)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2145223A JPH0439494A (ja) 1990-06-01 1990-06-01 エレクトロフュージョン継手及びその製造方法

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2145223A JPH0439494A (ja) 1990-06-01 1990-06-01 エレクトロフュージョン継手及びその製造方法

Publications (1)

Publication Number Publication Date
JPH0439494A true JPH0439494A (ja) 1992-02-10

Family

ID=15380200

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2145223A Pending JPH0439494A (ja) 1990-06-01 1990-06-01 エレクトロフュージョン継手及びその製造方法

Country Status (1)

Country Link
JP (1) JPH0439494A (ja)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2742691A1 (fr) * 1995-12-22 1997-06-27 Etex De Rech Tech Soc Element de raccord thermoplastique pour un assemblage de pieces par soudage selon une surface de jonction ouverte
FR2748415A1 (fr) * 1996-05-09 1997-11-14 Etex De Rech Tech Soc Element de raccord pour un assemblage de pieces en materiaux thermoplastiques par soudage et procede de fabrication d'un tel element
EP1079167A1 (en) * 1999-08-27 2001-02-28 Uponor Innovation Ab Electrofusion fitting
JP2006342961A (ja) * 2005-05-09 2006-12-21 Nippon Shiigatekku Kk 配管の接続構造
WO2007096611A1 (en) * 2006-02-21 2007-08-30 Polymer Welding Technologies Limited Jointing of plastics materials
JP2015513653A (ja) * 2012-03-13 2015-05-14 マリキャップ オーワイ 管継手及び管継手を形成する方法
EP3254832A1 (fr) * 2016-06-10 2017-12-13 Girpi Elément de raccord, raccord avec un tel élément et procédé de fabrication d'un élément de raccord

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2742691A1 (fr) * 1995-12-22 1997-06-27 Etex De Rech Tech Soc Element de raccord thermoplastique pour un assemblage de pieces par soudage selon une surface de jonction ouverte
FR2748415A1 (fr) * 1996-05-09 1997-11-14 Etex De Rech Tech Soc Element de raccord pour un assemblage de pieces en materiaux thermoplastiques par soudage et procede de fabrication d'un tel element
EP1079167A1 (en) * 1999-08-27 2001-02-28 Uponor Innovation Ab Electrofusion fitting
JP2006342961A (ja) * 2005-05-09 2006-12-21 Nippon Shiigatekku Kk 配管の接続構造
WO2007096611A1 (en) * 2006-02-21 2007-08-30 Polymer Welding Technologies Limited Jointing of plastics materials
JP2015513653A (ja) * 2012-03-13 2015-05-14 マリキャップ オーワイ 管継手及び管継手を形成する方法
EP3254832A1 (fr) * 2016-06-10 2017-12-13 Girpi Elément de raccord, raccord avec un tel élément et procédé de fabrication d'un élément de raccord
FR3052531A1 (fr) * 2016-06-10 2017-12-15 Girpi Element de raccord, raccord avec un tel element et procede de fabrication d'un element de raccord

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