JPH08247370A - Plastic pipe and plastic pipe joint - Google Patents

Plastic pipe and plastic pipe joint

Info

Publication number
JPH08247370A
JPH08247370A JP7050867A JP5086795A JPH08247370A JP H08247370 A JPH08247370 A JP H08247370A JP 7050867 A JP7050867 A JP 7050867A JP 5086795 A JP5086795 A JP 5086795A JP H08247370 A JPH08247370 A JP H08247370A
Authority
JP
Japan
Prior art keywords
joint
plastic
pipes
layer
plastic pipe
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
JP7050867A
Other languages
Japanese (ja)
Inventor
Hiroyuki Nishimura
寛之 西村
Tetsuo Ishikawa
哲夫 石川
Junsuke Kyomen
純輔 京免
Masayuki Sakaguchi
真幸 坂口
Hideki Bai
秀樹 倍
Taku Tago
卓 多胡
Shigenori Nagamatsu
茂儀 永松
Yuichiro Goto
雄一郎 後藤
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.)
Kubota Corp
Osaka Gas Co Ltd
Original Assignee
Kubota Corp
Osaka Gas Co 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 Kubota Corp, Osaka Gas Co Ltd filed Critical Kubota Corp
Priority to JP7050867A priority Critical patent/JPH08247370A/en
Publication of JPH08247370A publication Critical patent/JPH08247370A/en
Pending legal-status Critical Current

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
    • 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
    • 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"
    • B29C65/36—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" heated by induction
    • B29C65/3604—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" heated by induction characterised by the type of elements heated by induction which remain in the joint
    • B29C65/362—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" heated by induction characterised by the type of elements heated by induction which remain in the joint comprising at least a single wire, e.g. in the form of a winding
    • 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
    • B29C66/5224—Joining tubular articles for forming fork-shaped connections, e.g. for making Y-shaped pieces
    • B29C66/52241—Joining tubular articles for forming fork-shaped connections, e.g. for making Y-shaped pieces with two right angles, e.g. for making T-shaped pieces
    • 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
    • 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
    • B29C66/52293—Joining tubular articles involving the use of a socket said socket comprising a stop said stop being external
    • 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
    • B29C66/72—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 structure of the material of the parts to be joined
    • B29C66/723—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 structure of the material of the parts to be joined being multi-layered
    • 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
    • B29C65/342—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 comprising at least a single wire, e.g. in the form of a winding
    • 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"
    • B29C65/36—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" heated by induction
    • B29C65/3668—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" heated by induction characterised by the means for supplying heat to said heated elements which remain in the join, e.g. special induction coils
    • 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"
    • B29C65/36—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" heated by induction
    • B29C65/3672—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" heated by induction characterised by the composition of the elements heated by induction which remain in the joint
    • B29C65/3676—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" heated by induction characterised by the composition of the elements heated by induction which remain in the joint being metallic
    • 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)
  • Branch Pipes, Bends, And The Like (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)

Abstract

PURPOSE: To eliminate the scrape process, and improve workability at the time when plastic pipes are joined, in the plastic pipes, the junctions of which are made up of at least two layers, by making the fluidity of the surface layer greater than that of the inside layer. CONSTITUTION: When plastic pipes 10 are joined, the tips of the pipes 10 are inserted into sockets 18 of a joint 16, the joint 16 and the pipes 10 are fixed by use of a fixing tool, and a work coil 26 is arranged around the joint 16. In this state, when high frequency power is given from a high frequency power supply 28 to the work coil 26, high frequency current is given to a magnetic alloy heater 22 of the joint 16 by electromagnetic induction, and the heater 22 suddenly release heat by the skin effect to melt the outside surface of the pipes 10 and the inside surface of the joint 16 at the temperatures close to Curie temperature. At this time, the surface layer 14 of great fluidity flows together with oxide films and dirty layers, and a new, molten plastic of the inside layer 12 appears on the joining surfaces. Thus, the molten plastic of the inside layer 12 and the molten plastic of a joint body 20 are mixed and fused with each other.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】この発明はプラスチック管および
プラスチック管継手に関し、特にたとえばポリオレフィ
ン系樹脂からなり、電気融着接合される、プラスチック
管およびプラスチック管継手に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic pipe and a plastic pipe joint, and more particularly to a plastic pipe and a plastic pipe joint which are made of, for example, a polyolefin resin and which are electrically fusion bonded.

【０００２】[0002]

【従来の技術】ポリエチレンやポリプロピレン等のよう
なポリオレフィン系樹脂からなるプラスチック管を接合
する方法としては、たとえば図７に示すような継手１を
用いる方法が知られている。継手１は、接合すべき管２
および３と同じポリオレフィン系樹脂からなる本体４を
含み、本体４の内面すなわち管２および３との接合面の
近傍には、所定のキュリー温度を有しかつ溶融プラスチ
ック通路５が形成された磁性合金ヒータ６が設けられ
る。2. Description of the Related Art As a method for joining a plastic pipe made of a polyolefin resin such as polyethylene or polypropylene, a method using a joint 1 as shown in FIG. 7 is known. The joint 1 is a pipe 2 to be joined
A magnetic alloy having a predetermined Curie temperature and a molten plastic passage 5 formed in the vicinity of the inner surface of the main body 4, that is, the joint surface with the tubes 2 and 3 A heater 6 is provided.

【０００３】接合時には、管２および３の先端部外面の
酸化膜や汚れ層等をスクレープ（削り落とすこと）した
後、これらを継手１の受口に挿入し、継手１の周囲にワ
ークコイル７を配置して高周波電源８からワークコイル
７に高周波電力を付与する。すると、磁性合金ヒータ６
に電磁誘導によって高周波電流が付与され、表皮効果に
よってヒータ６が急激に発熱し、キュリー温度近傍で、
継手１と管２および３との接合面が融着される。At the time of joining, after scraping (shaving off) an oxide film, a dirt layer and the like on the outer surfaces of the tip portions of the pipes 2 and 3, these are inserted into the socket of the joint 1 and the work coil 7 is provided around the joint 1. And the high-frequency power source 8 applies high-frequency power to the work coil 7. Then, the magnetic alloy heater 6
A high frequency current is applied to the heater 6 due to electromagnetic induction, the heater 6 rapidly heats up due to the skin effect, and near the Curie temperature,
The joint surfaces of the joint 1 and the pipes 2 and 3 are fused.

【０００４】[0004]

【発明が解決しようとする課題】従来技術では、管２お
よび３の表面をスクレープするスクレープ工程が必要で
あった。このスクレープ工程は、十分な融着強度を確保
するために必要な工程であり、この工程を経ないで接合
した場合には、たとえば図８に示すように、管２（およ
び３）と本体４との間に介在する酸化膜９によって溶融
プラスチックどうしの混合が妨げられるので、十分な融
着強度が得られなかった。したがって、従来技術では、
スクレープ工程を省くことができず、接合時の作業性が
悪いという問題点があった。The prior art required a scraping step to scrape the surfaces of tubes 2 and 3. This scraping step is a step necessary to secure a sufficient fusion bonding strength, and when joining without passing through this step, as shown in FIG. 8, for example, as shown in FIG. Since the oxide film 9 interposed between and prevents the molten plastics from being mixed with each other, sufficient fusion strength cannot be obtained. Therefore, in the prior art,
There was a problem that the scraping process could not be omitted and the workability at the time of joining was poor.

【０００５】それゆえに、この発明の主たる目的は、ス
クレープ工程を省略して接合時の作業性を向上できる、
プラスチック管およびプラスチック管継手を提供するこ
とである。Therefore, the main object of the present invention is to improve the workability at the time of joining by omitting the scraping step.
It is to provide a plastic pipe and a plastic pipe joint.

【０００６】[0006]

【課題を解決するための手段】第１の発明は、少なくと
も接合部を２層としたプラスチック管であって、表面層
の流動性を内層の流動性よりも大きくした、プラスチッ
ク管である。第２の発明は、少なくともパイプ接合部を
２層としたプラスチック管継手であって、表面層の流動
性を内層の流動性よりも大きくした、プラスチック管継
手である。A first aspect of the present invention is a plastic pipe having at least a joint portion in two layers, in which the fluidity of the surface layer is larger than that of the inner layer. A second aspect of the present invention is a plastic pipe joint in which at least a pipe joint portion has two layers, and the fluidity of the surface layer is larger than that of the inner layer.

【０００７】[0007]

【作用】プラスチック管またはプラスチック管継手の少
なくとも接合部を２層とし、表面層の流動性（ＭＩ：メ
ルトインデックスまたはＭＦＲ：メルトフローレート）
を内層の流動性より大きくする。プラスチック管または
プラスチック管継手の接合時に接合面近傍に設けられた
加熱ヒータに電流を付与すると、加熱ヒータが発熱し、
接合部が溶融される。このとき、酸化膜や汚れ層が流動
性の大きな表面層とともに流動し、内層の新たな溶融プ
ラスチックが接合面に現れる。したがって、接合部にお
いては、内層の新たな溶融プラスチックと相手方の溶融
プラスチックとが十分に混合され得るので、十分な融着
強度が得られる。[Function] At least the joint portion of the plastic pipe or the plastic pipe joint is made into two layers, and the fluidity of the surface layer (MI: melt index or MFR: melt flow rate)
Is greater than the fluidity of the inner layer. When an electric current is applied to the heater provided near the joint surface when joining the plastic pipe or the plastic pipe joint, the heater will generate heat,
The joint is melted. At this time, the oxide film and the dirt layer flow together with the highly fluid surface layer, and new molten plastic of the inner layer appears on the joint surface. Therefore, in the joined portion, the new molten plastic of the inner layer and the molten plastic of the other side can be sufficiently mixed, so that sufficient fusion bonding strength can be obtained.

【０００８】[0008]

【発明の効果】この発明によれば、予めスクレープしな
くても、十分な融着強度が得られるので、スクレープ工
程を省略でき、したがって、接合時の作業性を向上でき
る。この発明の上述の目的，その他の目的，特徴および
利点は、図面を参照して行う以下の実施例の詳細な説明
から一層明らかとなろう。According to the present invention, since sufficient fusion bonding strength can be obtained without scraping in advance, the scraping step can be omitted and therefore workability at the time of joining can be improved. The above-mentioned objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of the embodiments with reference to the drawings.

【０００９】[0009]

【実施例】図１および図２に示すこの実施例のプラスチ
ック管１０は、ポリエチレンやポリプロピレン等のよう
なポリオレフィン系樹脂からなる内層１２を含み、内層
１２の外面には、内層１２と同じポリオレフィン系樹脂
からなり、かつその流動性が内層１２の流動性よりも大
きい表面層１４が形成される。たとえば、管１０がＡ種
のガス用管の場合には、内層１２および表面層１４の流
動性を０．１５〜０．４の間に設定しなければならない
ので、内層１２の流動性をＭＩ1 とし、表面層１４の流
動性をＭＩ2 とすると、ＭＩ1 およびＭＩ2 は、数１を
満足するように設定される。1 and 2, a plastic tube 10 of this embodiment includes an inner layer 12 made of a polyolefin resin such as polyethylene or polypropylene, and the outer surface of the inner layer 12 has the same polyolefin material as the inner layer 12. A surface layer 14 made of resin and having a fluidity larger than that of the inner layer 12 is formed. For example, when the pipe 10 is a type A gas pipe, the fluidity of the inner layer 12 and the surface layer 14 must be set between 0.15 and 0.4. 1, and when the fluidity of the surface layer 14 and MI 2, MI 1 and MI 2 is set so as to satisfy the equation (1).

【００１０】[0010]

【数１】０．１５＜ＭＩ1 ＜ＭＩ2 ＜０．４ なお、表面層１４は少なくとも接合部すなわち管１０の
先端部外面に設けられておればよく、必ずしも内層１２
の外面全体に設けられる必要はない。管１０の接合時に
は、図１に示すように、管１０の先端を継手１６の受口
１８に挿入する。継手１６は、管１０と同じポリオレフ
ィン系樹脂からなる本体２０を含み、本体２０の内面す
なわち管１０との接合面近傍には、所定のキュリー温度
を有する磁性合金線によって略円筒状に編まれた磁性合
金ヒータ２２が設けられる。この磁性合金ヒータ２２の
編目２４が溶融プラスチック通路となる。なお、磁性合
金ヒータ２２としてはパンチングメタル等のような他の
形式のものが用いられてもよいが、いずれの場合でも、
磁性合金ヒータ２２の表面と裏面とを貫通する溶融プラ
スチック通路が必要である。## EQU1 ## 0.15 <MI 1 <MI 2 <0.4 The surface layer 14 may be provided at least on the joint portion, that is, on the outer surface of the distal end portion of the tube 10, and is not necessarily the inner layer 12.
Need not be provided over the entire outer surface of the. At the time of joining the pipes 10, as shown in FIG. 1, the tip of the pipe 10 is inserted into the socket 18 of the joint 16. The joint 16 includes a main body 20 made of the same polyolefin resin as the pipe 10, and is knitted into a substantially cylindrical shape by a magnetic alloy wire having a predetermined Curie temperature on the inner surface of the main body 20, that is, in the vicinity of the joint surface with the pipe 10. A magnetic alloy heater 22 is provided. The stitch 24 of the magnetic alloy heater 22 serves as a molten plastic passage. The magnetic alloy heater 22 may be of another type such as punching metal, but in any case,
A molten plastic passage is required through the front and back of the magnetic alloy heater 22.

【００１１】継手１６の受口１８に管１０の先端を挿入
した後、継手１６と管１０とを図示しない固定治具を用
いて固定し、継手１６の周囲にワークコイル２６を配置
する。このワークコイル２６としては、たとえば特願平
５−７３４０７号に開示されたもの等が用いられ得る。
そして、高周波電源２８からワークコイル２６に高周波
電力を付与する。すると、継手１６の磁性合金ヒータ２
２に電磁誘導によって高周波電流が付与され、表皮効果
によってヒータ２２が急激に発熱し、キュリー温度近傍
で管１０の外面と継手１６の内面とが溶融される。この
とき、流動性が大きい表面層１４が酸化膜や汚れ層とと
もに容易に流動され、接合面に内層１２の新たな溶融プ
ラスチックが現れる。そして、この内層１２の溶融プラ
スチックと継手１６（本体２０）の溶融プラスチックと
がヒータ２２の溶融プラスチック通路２４を通して図３
に示すように互いに混合される。After inserting the tip of the pipe 10 into the receiving port 18 of the joint 16, the joint 16 and the pipe 10 are fixed using a fixing jig (not shown), and the work coil 26 is arranged around the joint 16. As the work coil 26, for example, one disclosed in Japanese Patent Application No. 5-73407 may be used.
Then, high frequency power is applied from the high frequency power supply 28 to the work coil 26. Then, the magnetic alloy heater 2 of the joint 16
A high-frequency current is applied to 2 by electromagnetic induction, the heater 22 rapidly generates heat due to the skin effect, and the outer surface of the pipe 10 and the inner surface of the joint 16 are melted near the Curie temperature. At this time, the surface layer 14 having high fluidity is easily flown together with the oxide film and the dirt layer, and new molten plastic of the inner layer 12 appears on the joint surface. The molten plastic of the inner layer 12 and the molten plastic of the joint 16 (main body 20) pass through the molten plastic passage 24 of the heater 22 as shown in FIG.
Are mixed with each other as shown in.

【００１２】そして、所定時間経過後、高周波電源２８
をオフし、継手１６の周囲に配置したワークコイル２６
を取り外し、管１０と継手１６との接合部（融着部）を
冷却する。この実施例によれば、融着時に管１０の表面
に生じた酸化膜や汚れ層が表面層１４とともに容易に流
動され得るので、内層１２の新たな溶融プラスチックと
継手１６（本体２０）の溶融プラスチックとが接合部に
おいて十分に混合され得る。したがって、酸化膜や汚れ
層を予めスクレープしなくても十分な融着強度が得られ
る。After a lapse of a predetermined time, the high frequency power source 28
Is turned off, and the work coil 26 is arranged around the joint 16.
Is removed, and the joint portion (fusion portion) between the pipe 10 and the joint 16 is cooled. According to this embodiment, since the oxide film and the dirt layer generated on the surface of the pipe 10 during the fusion can be easily flowed together with the surface layer 14, the new molten plastic of the inner layer 12 and the fusion of the joint 16 (main body 20) are melted. The plastic can be mixed well at the joint. Therefore, sufficient fusing strength can be obtained without previously scraping the oxide film and the dirt layer.

【００１３】なお、上述の実施例では、管１０の先端を
２層に形成した場合を示したが、たとえば図４に示すよ
うに、継手（ヘッダ）３０の差口３２を２層に形成する
ようにしてもよいし、また、図５または図６に示すよう
に、継手（両受ソケット）３４または３６の受口３８ま
たは４０を２層に形成するようにしてもよい。ここで、
継手３４（図５）は、その外面に電熱線４２が巻回され
た流動性の高いポリオレフィン系樹脂からなるマット４
４をそれよりも流動性の低い本体４６の内面（接合面）
に設けたものであり、継手３６（図６）は、流動性の高
いポリオレフィン系樹脂（表面層）４８で被覆された電
熱線５０を表面層４８よりも流動性の低いポリオレフィ
ン系樹脂からなる本体５２の内面（接合面）近傍に螺旋
状に設けたものである。電熱線４２（図５）および５０
（図６）には、それぞれの両端に設けられた端子５４お
よび５６から直接電流が付与される。In the above-described embodiment, the case where the tip of the pipe 10 is formed in two layers is shown. However, as shown in FIG. 4, for example, the inlet 32 of the joint (header) 30 is formed in two layers. Alternatively, as shown in FIG. 5 or 6, the socket 38 or 40 of the joint (both sockets) 34 or 36 may be formed in two layers. here,
The joint 34 (FIG. 5) has a mat 4 made of a highly fluid polyolefin resin having a heating wire 42 wound around its outer surface.
4 is an inner surface (bonding surface) of the main body 46 having lower fluidity
The joint 36 (FIG. 6) has a heating wire 50 covered with a highly fluid polyolefin resin (surface layer) 48 and is made of a polyolefin resin having a fluidity lower than that of the surface layer 48. It is provided spirally in the vicinity of the inner surface (joint surface) of 52. Heating wires 42 (FIG. 5) and 50
A current is directly applied to (FIG. 6) from terminals 54 and 56 provided at both ends of each.

【図面の簡単な説明】[Brief description of drawings]

【図１】この発明の一実施例のプラスチック管の接合状
態を示す図解図である。FIG. 1 is an illustrative view showing a joined state of a plastic pipe according to an embodiment of the present invention.

【図２】この発明の一実施例のプラスチック管を示す斜
視図である。FIG. 2 is a perspective view showing a plastic pipe according to an embodiment of the present invention.

【図３】この発明の一実施例のプラスチック管を用いた
接合部の状態を示す図解図である。FIG. 3 is an illustrative view showing a state of a joint portion using a plastic pipe according to an embodiment of the present invention.

【図４】この発明の他の実施例を示す図解図である。FIG. 4 is an illustrative view showing another embodiment of the present invention.

【図５】この発明の他の実施例を示す図解図である。FIG. 5 is an illustrative view showing another embodiment of the present invention.

【図６】この発明の他の実施例を示す図解図である。FIG. 6 is an illustrative view showing another embodiment of the present invention.

【図７】従来技術を示す図解図である。FIG. 7 is an illustrative view showing a conventional technique.

【図８】従来技術を用いた接合部の状態を示す図解図で
ある。FIG. 8 is an illustrative view showing a state of a joint portion using a conventional technique.

【符号の説明】[Explanation of symbols]

１０ …プラスチック管 １２ …内層 １４ …表面層 １６，３０，３４，３６ …継手 １８ …受口 ２０ …本体 ２２ …磁性合金ヒータ ２４ …溶融プラスチック通路 ２６ …ワークコイル 10 ... Plastic tube 12 ... Inner layer 14 ... Surface layer 16, 30, 34, 36 ... Joint 18 ... Receptacle 20 ... Main body 22 ... Magnetic alloy heater 24 ... Molten plastic passage 26 ... Work coil

───────────────────────────────────────────────────── フロントページの続き (72)発明者 京免 純輔 大阪府堺市石津北町64番地 株式会社クボ タビニルパイプ工場内 (72)発明者 坂口 真幸 大阪府堺市石津北町64番地 株式会社クボ タビニルパイプ工場内 (72)発明者 倍 秀樹 大阪府堺市石津北町64番地 株式会社クボ タビニルパイプ工場内 (72)発明者 多胡 卓 大阪府堺市石津北町64番地 株式会社クボ タビニルパイプ工場内 (72)発明者 永松 茂儀 大阪府堺市石津北町64番地 株式会社クボ タビニルパイプ工場内 (72)発明者 後藤 雄一郎 大阪府堺市石津北町64番地 株式会社クボ タビニルパイプ工場内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junsuke Kyoen 64 Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Vinyl Pipe Factory, Inc. (72) Inventor, Masayuki 64, Ishizukitamachi Sakai City, Osaka Kubota Vinyl Pipe Factory, Ltd. (72) Inventor Hideki Baiki 64, Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Vinyl Pipe Factory, Inc. (72) Inventor Taku Taka, 64, Ishizukitamachi, Sakai City, Osaka Prefecture (72) Inventor Shigeru Nagamatsu No. 64, Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Vinyl Pipe Co., Ltd. (72) Inventor, Yuichiro Goto 64, Ishizukitamachi, Sakai City, Osaka Kubota Vinyl Pipe Factory, Ltd.

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】少なくとも接合部を２層としたプラスチッ
ク管であって、 表面層の流動性を内層の流動性よりも大きくした、プラ
スチック管。Claim: What is claimed is: 1. A plastic pipe having at least two joint portions, wherein the fluidity of the surface layer is larger than that of the inner layer. 【請求項２】少なくともパイプ接合部を２層としたプラ
スチック管継手であって、 表面層の流動性を内層の流動性よりも大きくした、プラ
スチック管継手。2. A plastic pipe joint having at least two pipe joint portions, wherein the surface layer has a fluidity greater than that of the inner layer.
JP7050867A 1995-03-10 1995-03-10 Plastic pipe and plastic pipe joint Pending JPH08247370A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7050867A JPH08247370A (en) 1995-03-10 1995-03-10 Plastic pipe and plastic pipe joint

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7050867A JPH08247370A (en) 1995-03-10 1995-03-10 Plastic pipe and plastic pipe joint

Publications (1)

Publication Number Publication Date
JPH08247370A true JPH08247370A (en) 1996-09-27

Family

ID=12870683

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7050867A Pending JPH08247370A (en) 1995-03-10 1995-03-10 Plastic pipe and plastic pipe joint

Country Status (1)

Country Link
JP (1) JPH08247370A (en)

Similar Documents

Publication Publication Date Title
CA1193641A (en) Bifilar resistance element, heating element made therefrom, and process for preparing heating element made therefrom
JPH03213327A (en) Method and connecting member to connect plastic part by heat welding
JPH05196187A (en) Connecting method of pipe and joint
JPH09170692A (en) Work coil for inductive fusion method for inductive fusion
JPH08247370A (en) Plastic pipe and plastic pipe joint
JPH09144977A (en) Electric fusion connector
JP3677803B2 (en) Welding method for thermoplastic resin tube
JPH10220676A (en) Electrically fused joint for synthetic resin pipe
JPH08200581A (en) Welding method for plastic pipe
JPH10246382A (en) Electrofusion joint for synthetic resin pipe
JP2722334B2 (en) Joining method of ethylene resin pipe and joining structure thereof
JPH10160081A (en) Joint for synthetic resin pipe
JPH0389095A (en) Thermoplastic pipe joint and manufacture thereof
JPH0911335A (en) Joining method for polyethylene pipe, joining structure thereof, and joint for said pipe
JPH06278211A (en) Work coil and induction welding system
PL180631B1 (en) Electrofusion apparatus and method
JPH11304071A (en) Joint for plastic pipe and pipe connecting method
JPH0842774A (en) Electrically fusion-welded joint
JP2985588B2 (en) Method for joining electrofusion joint and thermoplastic resin molded article
JPH06281079A (en) Work coil for high-frequency power supply
JPH09229280A (en) Two-layer fusion pipe joint and manufacture therefor
JP2914600B2 (en) Electric fusion joint
JPS59166787A (en) Pipe connector, which can be melted and bonded, manufacture of pipe connector and method of connecting pipe using pipe connector
JP2590406Y2 (en) Electric welding pipe fittings
JP2002144433A (en) Sleeve tube and connecting structure for piping material using this sleeve tube to joint

Legal Events

Date Code Title Description
A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20030225