JP2817582B2 - Electrofusion method of thermoplastic pipe - Google Patents

Electrofusion method of thermoplastic pipe

Info

Publication number
JP2817582B2
JP2817582B2 JP5205190A JP20519093A JP2817582B2 JP 2817582 B2 JP2817582 B2 JP 2817582B2 JP 5205190 A JP5205190 A JP 5205190A JP 20519093 A JP20519093 A JP 20519093A JP 2817582 B2 JP2817582 B2 JP 2817582B2
Authority
JP
Japan
Prior art keywords
fusion
joint
time
diameter
energization
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.)
Expired - Fee Related
Application number
JP5205190A
Other languages
Japanese (ja)
Other versions
JPH0752259A (en
Inventor
均 浅野
克範 藤村
幸市 北尾
貞夫 小澤
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.)
JFE Engineering Corp
Original Assignee
JFE Engineering Corp
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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Application filed by JFE Engineering Corp filed Critical JFE Engineering Corp
Priority to JP5205190A priority Critical patent/JP2817582B2/en
Publication of JPH0752259A publication Critical patent/JPH0752259A/en
Application granted granted Critical
Publication of JP2817582B2 publication Critical patent/JP2817582B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related 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
    • 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
    • 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
    • B29C66/50—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
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
    • B29C66/912—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux
    • B29C66/9121—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the temperature
    • B29C66/91211—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the temperature with special temperature measurement means or methods
    • B29C66/91214—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the temperature with special temperature measurement means or methods by measuring the electrical resistance of a resistive element belonging to one of the parts to be welded, said element acting, e.g. as a thermistor
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
    • B29C66/912—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux
    • B29C66/9131—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the heat or the thermal flux, i.e. the heat flux
    • B29C66/91311—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the heat or the thermal flux, i.e. the heat flux by measuring the heat generated by Joule heating or induction heating
    • B29C66/91315—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the heat or the thermal flux, i.e. the heat flux by measuring the heat generated by Joule heating or induction heating by measuring the current intensity
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
    • B29C66/912—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux
    • B29C66/9131—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the heat or the thermal flux, i.e. the heat flux
    • B29C66/91311—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the heat or the thermal flux, i.e. the heat flux by measuring the heat generated by Joule heating or induction heating
    • B29C66/91317—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by measuring the temperature, the heat or the thermal flux by measuring the heat or the thermal flux, i.e. the heat flux by measuring the heat generated by Joule heating or induction heating by measuring the electrical resistance
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
    • B29C66/914—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux
    • B29C66/9161—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux by controlling or regulating the heat or the thermal flux, i.e. the heat flux
    • B29C66/91641—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux by controlling or regulating the heat or the thermal flux, i.e. the heat flux the heat or the thermal flux being non-constant over time
    • B29C66/91643—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux by controlling or regulating the heat or the thermal flux, i.e. the heat flux the heat or the thermal flux being non-constant over time following a heat-time profile
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
    • B29C66/914—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux
    • B29C66/9161—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux by controlling or regulating the heat or the thermal flux, i.e. the heat flux
    • B29C66/91651—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux by controlling or regulating the heat or the thermal flux, i.e. the heat flux by controlling or regulating the heat generated by Joule heating or induction heating
    • B29C66/91655—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux by controlling or regulating the heat or the thermal flux, i.e. the heat flux by controlling or regulating the heat generated by Joule heating or induction heating by controlling or regulating the current intensity
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/92—Measuring or controlling the joining process by measuring or controlling the pressure, the force, the mechanical power or the displacement of the joining tools
    • B29C66/922—Measuring or controlling the joining process by measuring or controlling the pressure, the force, the mechanical power or the displacement of the joining tools by measuring the pressure, the force, the mechanical power or the displacement of the joining tools
    • B29C66/9221—Measuring or controlling the joining process by measuring or controlling the pressure, the force, the mechanical power or the displacement of the joining tools by measuring the pressure, the force, the mechanical power or the displacement of the joining tools by measuring the pressure, the force or the mechanical power
    • B29C66/92211—Measuring or controlling the joining process by measuring or controlling the pressure, the force, the mechanical power or the displacement of the joining tools by measuring the pressure, the force, the mechanical power or the displacement of the joining tools by measuring the pressure, the force or the mechanical power with special measurement means or methods
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/97—Checking completion of joining or correct joining by using indications on at least one of the joined parts
    • B29C66/972—Checking completion of joining or correct joining by using indications on at least one of the joined parts by extrusion of molten material
    • 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
    • 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
    • B29C66/80—General aspects of machine operations or constructions and parts thereof
    • B29C66/81—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps
    • B29C66/812—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the composition, by the structure, by the intensive physical properties or by the optical properties of the material constituting the pressing elements, e.g. constituting the welding jaws or clamps
    • B29C66/8126—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the composition, by the structure, by the intensive physical properties or by the optical properties of the material constituting the pressing elements, e.g. constituting the welding jaws or clamps characterised by the intensive physical properties or by the optical properties of the material constituting the pressing elements, e.g. constituting the welding jaws or clamps
    • B29C66/81262—Electrical and dielectric properties, e.g. electrical conductivity
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/94—Measuring or controlling the joining process by measuring or controlling the time
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/95—Measuring or controlling the joining process by measuring or controlling specific variables not covered by groups B29C66/91 - B29C66/94
    • B29C66/959—Measuring or controlling the joining process by measuring or controlling specific variables not covered by groups B29C66/91 - B29C66/94 characterised by specific values or ranges of said specific variables
    • B29C66/9592—Measuring or controlling the joining process by measuring or controlling specific variables not covered by groups B29C66/91 - B29C66/94 characterised by specific values or ranges of said specific variables in explicit relation to another variable, e.g. X-Y diagrams
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/96—Measuring or controlling the joining process characterised by the method for implementing the controlling of the joining process
    • B29C66/961—Measuring or controlling the joining process characterised by the method for implementing the controlling of the joining process involving a feedback loop mechanism, e.g. comparison with a desired value
    • 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
    • B29C66/90—Measuring or controlling the joining process
    • B29C66/96—Measuring or controlling the joining process characterised by the method for implementing the controlling of the joining process
    • B29C66/967—Measuring or controlling the joining process characterised by the method for implementing the controlling of the joining process involving special data inputs or special data outputs, e.g. for monitoring purposes
    • B29C66/9672—Measuring or controlling the joining process characterised by the method for implementing the controlling of the joining process involving special data inputs or special data outputs, e.g. for monitoring purposes involving special data inputs, e.g. involving barcodes, RFID tags

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Branch Pipes, Bends, And The Like (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【産業上の利用分野】本発明は、熱可塑性電気融着継手
の熱可塑性プラスチック管への融着方法に関し、特に、
電気融着継手への通電時間過剰による異常加熱を継手の
口径を識別して未然に防止しうる電気融着方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for fusing a thermoplastic electrofusion joint to a thermoplastic pipe,
The present invention relates to an electric fusion method capable of preventing abnormal heating due to an excessive current supply time to an electric fusion joint by identifying the diameter of the joint and preventing it from occurring.

【０００２】[0002]

【従来の技術】電気融着継手は、ガス管等の熱可塑性プ
ラスチック管の継手として近年急速に普及しだしたもの
で、内周面に電熱線を埋め込んだ成形品である。管との
融着は、この電熱線に一定電圧で所定の電力を付与し、
界面を加熱溶融することにより行われる。通電時間は継
手の口径や種類に応じて予め設定された時間通電を行う
必要があるが、現場施工を簡略化するため、融着時に融
着材料の温度、材料の融解に伴う圧力等の特性変化をセ
ンサーで測定し、その情報に基づいて通電を自動的に停
止する融着方法がある(特開昭63−111394号公報、特開
平５−60288号公報）。これらの方法では、定量的でか
つ安定した結果が得られるが、管と継手の差し込み不
足、センサー部のプラグ差し込み不良等の原因により所
定の通電時間が過ぎても通電が自動的に終了しないこと
があった。これらの原因により過剰に通電が長時間行わ
れた場合、融着材料の熱劣化、管の溶け落ち、電熱線の
短絡、発火等がおこる危険性があるため、所定の通電時
間を大幅に超えても通電が自動的に終了しない場合、通
電を強制的に停止させる必要があった。その防止手段と
して、通電開始時から継手の口径や種類に関係無く、一
律の時間で通電を強制停止する方法がある。しかし、口
径が大きくなれば融着時間も長くなるため、大口径管用
継手では従来と異なる時間に設定する必要があり、その
ためには従来の小口径管用継手と大口径管用継手を制御
装置が識別する必要がある。2. Description of the Related Art An electric fusion joint has rapidly spread in recent years as a joint for a thermoplastic pipe such as a gas pipe, and is a molded article in which a heating wire is embedded in an inner peripheral surface. The fusion with the tube gives a predetermined power to this heating wire at a constant voltage,
This is performed by heating and melting the interface. The energization time must be energized for a preset time according to the diameter and type of the joint. There is a fusion method in which a change is measured by a sensor and the power is automatically stopped based on the information (Japanese Patent Application Laid-Open Nos. 63-111394 and 5-60288). With these methods, quantitative and stable results can be obtained.However, energization is not automatically terminated even after the specified energization time has elapsed due to insufficient insertion of pipes and joints, poor plug insertion of the sensor part, etc. was there. Excessive energization for a long time due to these causes may cause thermal deterioration of the fusion material, melting of the tube, short-circuiting of the heating wire, ignition, etc. Even if the energization does not automatically end, it is necessary to forcibly stop the energization. As a preventive measure, there is a method of forcibly stopping the energization for a uniform time regardless of the diameter and type of the joint from the start of the energization. However, the larger the bore, the longer the fusion time. There is a need to.

【０００３】従来、この電気融着継手の識別方法として
は、継手内部に継手の種類に応じて異なる抵抗値の識別
用抵抗器を埋め込み、その抵抗値を測定することで継手
を識別する方法（特開昭58−131025号公報）、継手と一
体成形されたデータ記録板の穿孔の有無を光センサーに
より読みとることで識別する方法(特開平１−17269号公
報）、継手の電熱体に通電するための通電ターミナルを
継手の品種ごとに異なる径に設定し、この径を測定する
ことによってその品種を識別する方法（特開平４−8829
3号公報)、融着時に最初に検出された電流の大きさから
識別する方法（特公平３−27014号公報）などがある。Conventionally, as a method for identifying an electro-fusion joint, a method for identifying a joint by embedding an identification resistor having a different resistance value according to the type of the joint in the joint and measuring the resistance value ( JP-A-58-131025), a method of identifying the presence or absence of perforations in a data recording plate integrally formed with a joint by reading with an optical sensor (JP-A-1-17269), energizing an electric heater of the joint For setting the energizing terminal to a different diameter for each type of joint, and measuring the diameter to identify the type (JP-A-4-8829)
No. 3) and a method of discriminating from the magnitude of current detected first at the time of fusion (Japanese Patent Publication No. 3-27014).

【０００４】[0004]

【発明が解決しようとする課題】上記の継手の識別方法
では、継手に特別な認識抵抗やデータ記録版を付加する
必要があるために、継手の製造が煩雑となっていた。ま
た、通電ターミナルの径を品種ごとに異なる径に設定す
ることで識別する方法では、施工者がターミナル径を測
定する必要があり施工作業が煩雑となっていた。また、
一般に大口径管用継手では小口径管用継手に比べ融着時
に必要な総熱量が大きいため、融着作業用の融着制御装
置の出力も大きくする必要がある。しかし、出力を上げ
れば装置の大型化は避けられず携帯性が失われる。した
がって携帯性を考慮すれば、大口径管用の継手ではその
口径の種類に関係なく融着制御装置の最大出力を用いて
融着する必要が生じる。この場合、融着時に最初に検出
された電流値からだけでは、大口径管用継手の口径を識
別することはできない。In the above-described method for identifying a joint, it is necessary to add a special recognition resistance and a data recording plate to the joint, so that the manufacture of the joint is complicated. Further, in the method of identifying by setting the diameter of the energization terminal to a different diameter for each type, it is necessary for an installer to measure the terminal diameter, and the construction work is complicated. Also,
In general, a joint for a large-diameter pipe requires a larger total amount of heat at the time of fusion than a joint for a small-diameter pipe, and therefore, it is necessary to increase the output of the fusion control device for the fusion work. However, increasing the output inevitably increases the size of the device, resulting in loss of portability. Therefore, in consideration of portability, in the case of a large diameter pipe joint, it is necessary to perform fusion using the maximum output of the fusion control device regardless of the type of the diameter. In this case, the diameter of the large-diameter pipe joint cannot be identified only from the current value detected first at the time of fusion.

【０００５】そこで、本発明の主たる目的は、継手の口
径を簡便かつ確実に識別し、強制停止時間を口径毎に異
なる時間で設定しうる手段を提供することにある。Accordingly, it is a primary object of the present invention to provide means for easily and surely identifying the diameter of a joint and setting a forced stop time at a different time for each diameter.

【０００６】[0006]

【課題を解決するための手段】本発明は上記目的を達成
した口径の識別方法及び熱可塑性プラスチック管への電
気融着継手の融着接合方法を提供するものである。SUMMARY OF THE INVENTION The present invention provides a method of identifying a bore size and a method of fusion-splicing an electro-fusion joint to a thermoplastic pipe, which achieves the above objects.

【０００７】かかる口径の識別方法は、熱可塑性プラス
チック管を接続する際に、抵抗が温度依存性であってか
つ各口径毎に成分の異なる電熱線が埋設されている電気
融着継手を用い、融着制御装置により融着する際の通電
開始時の電流値または抵抗値および通電開始一定時間後
に電流値または抵抗値を測定し、これらの値を予め入力
してある値と照合させることを特徴としている。[0007] Such a method for identifying a diameter uses an electric fusion joint in which a heating pipe having a temperature-dependent resistance and a different component for each diameter is embedded when connecting a thermoplastic pipe. The current value or resistance value at the start of energization and the current value or resistance value after a certain period of time from the start of energization at the time of fusing by the fusion control device are measured, and these values are compared with a previously input value. And

【０００８】また、熱可塑性プラスチック管への電気融
着継手の融着接合方法は上記の方法により融着制御装置
に、口径を識別させた後、さらに総積算電力量又は融着
時間を検知させ、予め各口径毎に設定してある総積算電
力量又は融着時間と比較させ、総積算電力量又は融着時
間の範囲外となった場合に通電を停止させることを特徴
としている。[0008] In addition, the fusion bonding method of the electrofusion joint to the thermoplastic pipe is performed by causing the fusion control device to identify the diameter by the above-described method and further detecting the total integrated power amount or the fusion time. The present invention is characterized in that a comparison is made with a total integrated power amount or a fusing time set in advance for each aperture, and when the total power amount or the fusing time is out of the range, energization is stopped.

【０００９】熱可塑性プラスチック管の材質、肉厚、口
径等は用途等との関係で定まるが、材質は例えば塩化ビ
ニル樹脂、ポリエチレン樹脂、ポリプロピレン樹脂、ポ
リスチレン樹脂等である。The material, thickness, diameter, etc., of the thermoplastic plastic tube are determined depending on the application and the like, and the material is, for example, vinyl chloride resin, polyethylene resin, polypropylene resin, polystyrene resin and the like.

【００１０】電気融着継手は公知のいかなる構造のもの
でも適用でき、一般的にはソケット型であって内周面近
くに電熱線が埋設されているものである。The electric fusion joint may have any known structure, and is generally a socket type having a heating wire embedded near the inner peripheral surface.

【００１１】本発明においてはこの電熱線に、抵抗が温
度依存性であってかつ各口径毎に成分（抵抗の温度変
化）の異なるものを用いる。このような材質の組合せの
例として、ＪＩＳ Ｃ２５３２−１９９０で規定されて
いるＧＦＣ１４２Ｗ、ＧＦＣ１２３Ｗ、ＧＦＣ１１１
Ｗ、ＧＮＣ１１２Ｗ、ＧＮＣ１０８Ｗ、ＧＮＣ１０１
Ｗ、ＧＮＣ６９Ｗ、ＧＳＵ７２Ｗ、ＧＣＭ４４Ｗ、ＧＣ
Ｎ４９Ｗ、ＧＣＮ３０Ｗ、ＧＣＮ１５Ｗ、ＧＣＮ１０
Ｗ、ＧＣＮ５Ｗ、ＧＮＡ２８Ｗ、ＧＮ９．６Ｗ、ＧＣＮ
４９、ＧＣＮ３０、ＧＣＮ１５、ＧＣＮ１０、ＧＣＮ５
などから適宜選択して組合せればよい。In the present invention, a heating wire having a temperature-dependent resistance and a different component (temperature change in resistance) for each diameter is used as the heating wire. Examples of such a combination of materials include GFC142W, GFC123W, and GFC111 defined in JIS C2532-1990.
W, GNC112W, GNC108W, GNC101
W, GNC69W, GSU72W, GCM44W, GC
N49W, GCN30W, GCN15W, GCN10
W, GCN5W, GNA28W, GN9.6W, GCN
49, GCN30, GCN15, GCN10, GCN5
What is necessary is just to select suitably from combinations etc. and to combine them.

【００１２】電気融着継手には電熱線が埋設されるほ
か、この電熱線のターミナル、継手の融着面の溶融を検
知するセンサーの取付部等が適宜設けられる。A heating wire is buried in the electric fusion joint, and a terminal for the heating wire, a mounting portion for a sensor for detecting melting of the fusion surface of the joint, and the like are appropriately provided.

【００１３】融着制御装置は電熱線への供電部、この供
電の電流値または抵抗値の測定部、検出した電流値また
は抵抗値を予め入力してある値と照合して口径を識別す
る演算部等からなる。この予め入力させる値は各電気融
着接手（口径、材質等）と熱可塑性プラスチック管（口
径、材質等）について予め測定して求めておいた値であ
る。融着制御装置にはそのほかセンサーからの信号を検
知して供電の停止を指令する機槽等を適宜設けることが
できる。The fusion control device includes a power supply unit for the heating wire, a measurement unit for measuring the current value or resistance value of the power supply, and an operation for identifying the caliber by comparing the detected current value or resistance value with a previously input value. Department. The value to be input in advance is a value previously measured and obtained for each electric fusion joint (diameter, material, etc.) and thermoplastic pipe (diameter, material, etc.). In addition, the fusion control device may be appropriately provided with a machine tank or the like that detects a signal from a sensor and instructs a stop of power supply.

【００１４】[0014]

【作用】一般に小口径管用継手では大口径管用継手に比
べ融着時に必要な総熱量が少ないため、電熱線の発熱量
を抑えても短時間で融着は可能である。このため電熱線
の抵抗値は大口径管用に比べ大きくすることが可能であ
る。そこで、小口径管用継手で使用する電熱線の抵抗値
を大口径管用継手に比べ大きくすれば、通電開始時の電
流値または抵抗値を測定することで、容易に小口径管用
と大口径管用を識別することが可能となる。In general, the joint for small-diameter pipes requires less total heat in fusion than the joint for large-diameter pipes, so that fusion can be performed in a short time even if the heating value of the heating wire is suppressed. For this reason, the resistance value of the heating wire can be made larger than that for a large diameter pipe. Therefore, if the resistance value of the heating wire used in the small-diameter pipe joint is made larger than that of the large-diameter pipe joint, the current value or the resistance value at the start of energization can be measured to easily switch between the small-diameter pipe and the large-diameter pipe. It becomes possible to identify.

【００１５】さらに、また電熱線の成分を変えること
で、通電中の温度の上昇に伴う電流値および抵抗値の時
間毎の変化量を変えることができる。そこで通電を始め
てから一定時間後の電流値または抵抗値を測定し、通電
開始時の電流値または抵抗値と比較して、その変化量ま
たは積算電力量を知れば使用されている電熱線の種類を
判断することができる。したがって、口径別に電熱線の
種類を変えれば、容易に口径を識別することができる。Further, by changing the components of the heating wire, it is possible to change the amount of change in the current value and the resistance value with time as the temperature increases during energization. Therefore, the current value or resistance value after a certain period of time from the start of energization is measured, compared with the current value or resistance value at the start of energization, and if the change amount or integrated power amount is known, the type of heating wire used Can be determined. Therefore, if the type of heating wire is changed for each caliber, the caliber can be easily identified.

【００１６】以上の方法によれば継手の口径を簡便かつ
確実に識別し、強制停止時間を口径毎に異なる時間で設
定することができる。According to the above method, the diameter of the joint can be easily and reliably identified, and the forced stop time can be set to a different time for each diameter.

【００１７】[0017]

【実施例】図１は熱可塑性プラスチック管１とソケット
型電気融着継手２の接続状態を示す断面図である。この
ソケット型継手２の内周面には発熱体である電熱線３が
螺旋状に埋め込まれ、その電熱線３の両端各々は外周面
より突きだし、２つのコネクターピン４に接続されてい
る。電力は図３の融着制御装置32よりこのコネクターピ
ン４を介して印加される。また凹部５には融着制御装置
32から圧力センサー38が差し込まれる。凹部５の底部に
は電熱線の発熱により溶解膨張した材料が入り込み、凹
部５内にて高さを増し圧力センサー38の接点を押し上げ
る。この時点で通電は停止される。表1には口径サイズ7
5Ａ、100Ａ、150Ａ、および200Ａの各継手に用いたＪＩ
Ｓ規格品銅ニッケル線の種類を示した。FIG. 1 is a sectional view showing a connection state between a thermoplastic plastic tube 1 and a socket-type electric fusion joint 2. A heating wire 3 as a heating element is spirally embedded in the inner peripheral surface of the socket type joint 2, and both ends of the heating wire 3 protrude from the outer peripheral surface and are connected to two connector pins 4. Power is applied from the fusion control device 32 of FIG. Further, a fusion control device is provided in the recess 5.
A pressure sensor 38 is inserted from 32. The material that has melted and expanded due to the heat generated by the heating wire enters the bottom of the recess 5, increases the height in the recess 5, and pushes up the contact point of the pressure sensor 38. At this point, energization is stopped. Table 1 shows caliber size 7
JI used for 5A, 100A, 150A, and 200A joints
The types of S-standard copper nickel wires are shown.

【００１８】[0018]

【表１】 [Table 1]

【００１９】次に、図２はこれらの口径サイズのソケッ
ト型継手による定電圧下での電気融着時の電流の経時変
化を示した。図中、点線が垂直に下がるところが通電停
止位置である。Next, FIG. 2 shows the time-dependent change of the electric current at the time of electrofusion at a constant voltage by the socket type joints of these aperture sizes. In the figure, the position where the dotted line goes down vertically is the energization stop position.

【００２０】図３には融着制御装置の基本構成を示し
た。ＣＰＵ33には以下の様なプログラムを組み入れた。
通電の開始時に電流計39で電流値を計測させ、予めメモ
リー35に記憶させた設定値と比較させる。20Ａ未満なら
ば、小口径管と判断させ、250秒でスイッチ35により強
制停止させる。20Ａ以上であれば150秒後に電流計32で
再び電流値を測定し、メモリー34の値と比較させる。こ
こで15.50〜17.00Ａならば100Ａ管と、17.50〜20.00Ａ
ならば150Ａ管と、21.50〜24.00Ａならば200Ａ管と判断
させそれぞれ300秒、340秒、380秒で通電を強制停止さ
せる。FIG. 3 shows the basic configuration of the fusion control device. The following programs were incorporated in the CPU 33.
At the start of energization, the current value is measured by the ammeter 39 and compared with the set value stored in the memory 35 in advance. If it is less than 20A, it is determined to be a small-diameter tube, and forcibly stopped by the switch 35 in 250 seconds. If it is 20 A or more, the current value is measured again by the ammeter 32 after 150 seconds, and compared with the value of the memory 34. Here, if it is 15.50-17.00A, 100A tube and 17.50-20.00A
If so, it is determined that the tube is 150A, and if it is 21.50-24.00A, it is determined to be 200A, and the energization is forcibly stopped at 300, 340 and 380 seconds, respectively.

【００２１】この強制停止時間は環境温度23℃における
最適融着時間に120秒を加えたものである。This forced stop time is obtained by adding 120 seconds to the optimum fusing time at an environmental temperature of 23 ° C.

【００２２】上記の実施例では電流値により識別させて
いるが、抵抗値および付与した電力量の積算値で識別さ
せる態様でも行われる。In the above embodiment, the identification is made by the current value. However, the identification may be made by the resistance value and the integrated value of the applied electric energy.

【００２３】[0023]

【発明の効果】本発明によれば通電開始時および通電中
の電流値または抵抗値を測定することにより継手の口径
が簡便かつ確実に識別できるため、口径毎に異なる時間
で通電を強制停止できる。このため口径のサイズに関係
無く自動的に異常加熱を未然に防ぐことができる。本発
明の方法は継手自身に特別な加工を施すことなく、従来
の方法をそのまま適用できる。According to the present invention, the diameter of the joint can be easily and reliably identified by measuring the current value or resistance value at the start of energization and during energization, so that energization can be forcibly stopped at different times for each diameter. . For this reason, abnormal heating can be automatically prevented regardless of the size of the aperture. According to the method of the present invention, the conventional method can be applied without any special processing to the joint itself.

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

【図１】 熱可塑性プラスチック管をソケット型電気融
着接手で接続している状態を示す断面図である。FIG. 1 is a cross-sectional view showing a state in which a thermoplastic plastic tube is connected by a socket-type electric fusion joint.

【図２】 各口径のソケット型継手による定電圧下での
電気融着時の電流の経時変化の例を示すグラフである。FIG. 2 is a graph showing an example of a temporal change of a current at the time of electrofusion at a constant voltage by a socket type joint of each diameter.

【図３】 融着制御装置の構成例を示すブロック図であ
る。FIG. 3 is a block diagram illustrating a configuration example of a fusion control device.

【符号の説明】[Explanation of symbols]

１…熱可塑性プラスチック管 ２…電気融着継手 ３…電熱線 32…融着制御装置 DESCRIPTION OF SYMBOLS 1 ... Thermoplastic pipe 2 ... Electric fusion joint 3 ... Electric heating wire 32 ... Fusion control device

───────────────────────────────────────────────────── フロントページの続き (72)発明者 小澤 貞夫 東京都千代田区丸の内一丁目１番２号 日本鋼管株式会社内 (56)参考文献 特開 平２−196628（ＪＰ，Ａ) 特表 平３−506066（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) B29C 65/34 F16L 47/02 B29L 23:00──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Sadao Ozawa 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Inside Nippon Kokan Co., Ltd. (56) References JP-A-2-196628 (JP, A) Special Table Hei 3 -506066 (JP, A) (58) Fields investigated (Int. Cl. 6 , DB name) B29C 65/34 F16L 47/02 B29L 23:00

Claims (2)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】 熱可塑性プラスチック管を接続する際
に、抵抗が温度依存性であってかつ各口径毎に成分の異
なる電熱線が埋設されている電気融着継手を用い、融着
制御装置により融着する際の通電開始時の電流値または
抵抗値および通電開始一定時間後に電流値または抵抗値
を測定し、これらの値を予め入力してある値と照合させ
ることを特徴とする口径の識別方法When connecting a thermoplastic pipe, an electric fusion joint in which a resistance is temperature-dependent and a heating wire having a different component for each diameter is embedded is used, and a fusion control device is used. Measurement of the current value or resistance value at the start of energization at the time of fusion and the current value or resistance value after a certain period of time from the start of energization, and comparing these values with the values input in advance, identification of the aperture size Method 【請求項２】 請求項１に記載の方法により融着制御装
置に、口径を識別させた後、さらに総積算電力量又は融
着時間を検知させ、予め各口径毎に設定してある総積算
電力量又は融着時間と比較させ、総積算電力量又は融着
時間の範囲外となった場合に通電を停止させることを特
徴とする熱可塑性プラスチック管への電気融着継手の融
着接合方法2. The method according to claim 1, wherein the fusion control device identifies the caliber, and further detects the total integrated electric energy or the fusion time, and sets the total accumulation preset for each caliber. A method for fusing and joining an electro-fusion joint to a thermoplastic pipe, wherein the current is stopped when the total power or the fusing time is out of the range of the power amount or the fusing time.
JP5205190A 1993-08-19 1993-08-19 Electrofusion method of thermoplastic pipe Expired - Fee Related JP2817582B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5205190A JP2817582B2 (en) 1993-08-19 1993-08-19 Electrofusion method of thermoplastic pipe

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5205190A JP2817582B2 (en) 1993-08-19 1993-08-19 Electrofusion method of thermoplastic pipe

Publications (2)

Publication Number Publication Date
JPH0752259A JPH0752259A (en) 1995-02-28
JP2817582B2 true JP2817582B2 (en) 1998-10-30

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Publication number Priority date Publication date Assignee Title
KR20010047859A (en) * 1999-11-23 2001-06-15 오동찬 Socket type automatic welding device

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