GB2191146A - Method of producing a socket joint for a thermally insulated conduit - Google Patents

Method of producing a socket joint for a thermally insulated conduit Download PDF

Info

Publication number
GB2191146A
GB2191146A GB8713118A GB8713118A GB2191146A GB 2191146 A GB2191146 A GB 2191146A GB 8713118 A GB8713118 A GB 8713118A GB 8713118 A GB8713118 A GB 8713118A GB 2191146 A GB2191146 A GB 2191146A
Authority
GB
United Kingdom
Prior art keywords
temperature
welding
resistance wire
measuring means
socket
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB8713118A
Other versions
GB8713118D0 (en
Inventor
Jurgen Friessner
Peter Huber
Werner Szczepanek
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.)
Kabelmetal Electro GmbH
Original Assignee
Kabelmetal Electro GmbH
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 Kabelmetal Electro GmbH filed Critical Kabelmetal Electro GmbH
Publication of GB8713118D0 publication Critical patent/GB8713118D0/en
Publication of GB2191146A publication Critical patent/GB2191146A/en
Withdrawn legal-status Critical Current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"
    • B29C65/3472—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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials 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
    • B29C65/342—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
    • B29C65/3428—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 said at least a single wire having a waveform, e.g. a sinusoidal form
    • 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
    • B29C66/20—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
    • B29C66/22—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns
    • B29C66/229—Other specific patterns not provided for in B29C66/221 - B29C66/227
    • 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
    • B29C66/40—General aspects of joining substantially flat articles, e.g. plates, sheets or web-like materials; Making flat seams in tubular or hollow articles; Joining single elements to substantially flat surfaces
    • B29C66/41—Joining substantially flat articles ; Making flat seams in tubular or hollow articles
    • B29C66/43—Joining a relatively small portion of the surface of said articles
    • B29C66/432—Joining a relatively small portion of the surface of said articles for making tubular articles or closed loops, e.g. by joining several sheets ; for making hollow articles or hollow preforms
    • B29C66/4322—Joining a relatively small portion of the surface of said articles for making tubular articles or closed loops, e.g. by joining several sheets ; for making hollow articles or hollow preforms by joining a single sheet to itself
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/50—General aspects of joining tubular articles; General aspects of joining long products, i.e. bars or profiled elements; General aspects of joining single elements to tubular articles, hollow articles or bars; General aspects of joining several hollow-preforms to form hollow or tubular articles
    • B29C66/51—Joining tubular articles, profiled elements or bars; Joining single elements to tubular articles, hollow articles or bars; Joining several hollow-preforms to form hollow or tubular articles
    • B29C66/53—Joining single elements to tubular articles, hollow articles or bars
    • B29C66/532—Joining single elements to the wall of tubular articles, hollow articles or bars
    • B29C66/5326—Joining single elements to the wall of tubular articles, hollow articles or bars said single elements being substantially flat
    • 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
    • B29C66/7232—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 comprising a non-plastics layer
    • B29C66/72321—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 comprising a non-plastics layer consisting of metals or their alloys
    • 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
    • B29C66/727—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 porous, e.g. foam
    • 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
    • B29C66/91221—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 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
    • B29C66/90—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
    • B29C66/9141—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 temperature
    • B29C66/91411—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 temperature of the parts to be joined, e.g. the joining process taking the temperature of the parts to be joined into account
    • 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
    • B29C66/9141—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 temperature
    • B29C66/91441—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 temperature the temperature being non-constant over time
    • B29C66/91443—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 temperature the temperature being non-constant over time following a temperature-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
    • B29C66/91641—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
    • 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
    • B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
    • B29C66/919—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux characterised by specific temperature, heat or thermal flux values or ranges
    • 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
    • B29C66/919—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux characterised by specific temperature, heat or thermal flux values or ranges
    • B29C66/9192—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux characterised by specific temperature, heat or thermal flux values or ranges in explicit relation to another variable, e.g. temperature diagrams
    • B29C66/91921—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux characterised by specific temperature, heat or thermal flux values or ranges in explicit relation to another variable, e.g. temperature diagrams in explicit relation to another temperature, e.g. to the softening temperature or softening point, to the thermal degradation temperature or to the ambient temperature
    • 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
    • B29C66/919—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux characterised by specific temperature, heat or thermal flux values or ranges
    • B29C66/9192—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux characterised by specific temperature, heat or thermal flux values or ranges in explicit relation to another variable, e.g. temperature diagrams
    • B29C66/91951—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux characterised by specific temperature, heat or thermal flux values or ranges in explicit relation to another variable, e.g. temperature diagrams in explicit relation to time, e.g. temperature-time 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
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/19—Control of temperature characterised by the use of electric means
    • G05D23/1927—Control of temperature characterised by the use of electric means using a plurality of sensors
    • G05D23/193—Control of temperature characterised by the use of electric means using a plurality of sensors sensing the temperaure in different places in thermal relationship with one or more spaces
    • G05D23/1931—Control of temperature characterised by the use of electric means using a plurality of sensors sensing the temperaure in different places in thermal relationship with one or more spaces to control the temperature of one space
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/19—Control of temperature characterised by the use of electric means
    • G05D23/20—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature
    • G05D23/22—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature the sensing element being a thermocouple
    • 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
    • B29C65/3432—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 comprising several wires, e.g. in the form of several independent windings
    • 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
    • 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
    • B29C66/949—Measuring or controlling the joining process by measuring or controlling the time characterised by specific time values or ranges
    • 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
    • B29L2023/00—Tubular articles
    • B29L2023/22—Tubes or pipes, i.e. rigid
    • B29L2023/225—Insulated

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Remote Sensing (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
  • Branch Pipes, Bends, And The Like (AREA)
  • Manufacturing Of Electrical Connectors (AREA)

Abstract

A process for controlling the welding operation in the production of a socket joint for thermally insulated line pipes by means of resistance heating, where the temperature of the resistance wire is constantly measured during current passage. At a second measuring point, the temperature of the welding pool is measured between two windings of the wire. At first, the wire temperature, the maximum value of which is limited, is used as a controlled variable, and subsequently the welding pool temperature is used as a controlled variable, for the heating power. <IMAGE>

Description

SPECIFICATION Method of producing a socket joint for athermally insulated conduit This invention relates to a method of producing a socket joint between lengths ofthermally insulated conduit which each comprise an inner pipe surrounded by plastics insulation, the inner pipes being welded together, their joint being covered by a plastics socket which surrounds and is welded to the plastics outer layers ofthe lengths of conduit, one or more resistance wires being introduced in a meandering or spiral configuration between the socket and outer layers, the resistance wire(s) serving (upon a heating current being passed therethrough) to bring into a weldable condition the adjacent surface portions of the socket and outer layers, arid the requisiteweld- ing together of these surface portions taking place under pressure and heat.
Asocketjointforlengthsofthermallyinsulated conduit is known from German Utility Model 8204372, in which the ends of lengths of a plastics outer pipe are covered by means of a longitudinally split plastics socket, and the ends of these lengths of the outer pipe are welded to the socket and the surface portions defining the longitudinal gap ofthe socket are welded together. The welding is effected by means of a meandering resistance wire which is laid between the ends of the outer pipe and the socket, and which, upon current being passed through it, begins to melt the plastics material at the adjoining surfaces, so that the desired welding can be performed under pressure.In this type of welding, however, there is the riskthatthe plastics material may be decomposed ordegraded,forexample due to overheating in the welding area, so that a properweld cannot be produced. On the other hand, satisfactory welding likewise does not take place if the temperatures attained are too low. The temperature ofthe weld can be affected by environmental effects, e.g. those of the wind, ambienttem perature, or sun.
It is an object of the present invention to provide a method which will enable these environmental effectsto be eliminated and a durably firm weld to be achieved.
According to the present invention, there is provided a method of producing a socket joint between lengths ofthermally insulated conduit which each comprise an inner pipe surrounded by plastics insulation,theinnerpipes being welded together,their joint being covered by a plastics socket which surrounds and is welded to the plastics outer layers of the lengths of conduit, one or more resistance wires being introduced in a meandering or spiral configuration between the socket and outer layers, the resistance wire(s) serving (upon a heating current being passed therethrough) to bring into a weldable condition the adjacent surface portions of the socket and outer layers, and the requisite welding together of these surface portions taking place under pressure and heat, wherein the temperature ofthe resistance wire(s) is continually measured during passage of the heating current, a welding zone temperature between adjacent meanders orturns ofthe resistance wire(s) being measured at the same time, thetemperature ofthe resistance wire(s) being restricted so as not to exceed a maximum lying marginally below the decomposition or degradation temperature of the adjacent plastics material, and the welding zone temperature specified being utilised as a regulation variable, in that the heating power employed in the welding operation is regulated by reference to the variations in the said welding zone temperature.In a method according to the invention, overheating of the plastics material can be dependably avoided, and the plastics material at the surfaces to be welded can in every case be duly brought into a weldable condition.
It is particularly advantageous if the welding temperature is kept at a substantially constant value for a period of at least 10 seconds, preferably 30 to 180 seconds. The heating wire temperature is expediently controlled by altering the heating power, the heating current being continuously regulated over a range extending from a maximum value down to a value corresponding to the welding temperature. In practice, the heating power preferably is brought very quickly to the maximum value, the heating wire temperature thereafter being held virtually constant over an appropriate period by downward regulation ofthe current.As for the phasefollowing the attain ment ofthe maximum heating wire temperature, the said welding zonetemperaturewhich is used as a regulation variableforthe heating power or heating current may be a melttemperature,the heating wire temperature being limited to a maximum value. The regulation of the heating power may be obtained by means of a microprocessor. When the plastics components undergoing welding are of polyethylene, the maximum heating wire temperature is preferably fixed at 280#C, and the welding temperature is prefer ablyfixedatl40to 160.
The invention also includes an apparatus suitable for use in a method according to the invention, comprising atransformersuitablefor use in welding, el ectrical leads whereby the transformer's output is (in use) supplied to one or more resistance wires introduced in a meandering or spiral configuration between the socket and outer layers which are to be welded together, a microprocessorwhich (in use) controlstheheating poweremployed inthewelding operation, and electrical leads whereby (in use) the microprocessor receives inputs from two measuring means, these being a first measuring means which (in use) measures the temperature of the resistance wire(s) and a second measuring means which (in use) measures a welding zone temperature between adjacent meanders orturns of the resistance wi re(s).
Preferablythe said first and second measuring means make use of respective thermocouples. Thus the said first measuring means may make use of a thermocouple soldered, welded or otherwisethermally conductively connected to the (or a) resistance wire. Alternatively, this thermocouple may be connected to the (or a) resistance wire by means of clips.
An isolated measured-value amplifier advantageously may be connected between the said first measuring means and the microprocessor. This can serve to prevent the microprocessor being damaged by high voltage. It has proved expedient particularly in the case of sockets of large diameters, for example sockets for connecting district heating conduits with a nominalwidthofmorethan200mm,forthesaid second measuring means to make use of a plurality ofthermocouples, which are positioned in a welding pool; in this case the thermocouples should prefer- ably be evenly distributed around the periphery of the assembly. The above-mentioned welding zone temperature may be measured by means of at least one thermocouple fastened outside the respective welding zone.This can serve to preventthe thermocouple being displaced as a result of the pressure and softening ofthe plastics material occurring in the zone referred to. A displacement of the thermocouple, i.e. a change in the distance of the measuring point from the resistance wire, would mean that an accurate measurement of the temperature concerned would not be possible. For the same reason, where use is made of a resistance wire meander surrounding the said second measuring means, this preferably is fixed at at leastthree points, which occur preferably in the region of the curved sections ofthe resistance wire, by means offastening elements positioned outside the respective welding zone. This avoids the possibility that the pressure within the welding zone might displace the meander as well.
When use is made of one or more resistance wires laid in a spiral disposition, wherebyturns of wire run alongside one another in a circumferential direction, the relevantthermocouple(s) may advantageously be positioned in between two of these turns.
The invention is explained in more detail below with reference to the accompanying diagrammatic drawing, in which: Figure 1 is a side view of an assembly in use in a method according to the invention, Figure2 is an internal detail view for Figure 1, on an enlarged scale, and Figure 3 is a graph showing the course of the weld ing operation forthe assembly of Figures 1 and 2.
In Figure 1 two conduit end portions are shown at 1 and 2. These are end portions of a district heating conduit which comprises a heating-mediumconducting steel pipe, a thermal insulation of foamed material, and a plastics outer sheath. Typical district heating conduits are delivered in lengths of approximately 6 m. These lengths have to be joined up in situ. The individual lengths are so produced that the inner pipe protrudes at the ends from the foamed layer, so that easy welding together oftwo lengths of pipe is possible. For subsequent insula- tion of the weld joint, a plastics socket 3, in the form either of a plastics pipe or of a plastics band, is placed over the weld.Figure 1 shows a socket 3formed from a plastics band, which is wound, with its edges 4overlapping, aroundtheweldjoint uniting the conduit end portions 1 and 2. The socket 3 serves as a mould for plastics foam forming components introduced into the annular gap between the steel pipe and the socket 3, and also serves as a seal preventing the ingress of moisture. The socket 3 is welded both to the plastics outer sheath of the district heating conduit and at its overlapping edges 4. For this purpose, a resistance wire 14 is laid in a meandering configuration between the surfaces to be welded, and is connected, by means of supply leads 5 and 6, to a welding transformer 7, fed by the mains or some other source of E.M.F.When the welding trans- former7 is switched on, a current flows through the resistance wire 14, causing this wire to heat up and likewise heating up the adjoining plastics surfaces and rendering them weldable. By means not shown in the drawing, pressure is exerted on the weld, so thata durable weld joint is achieved. Forthe regulation of the welding operation, two measuring means 8 and 9 are provided; one measuring means 8 meas ures the temperature of the resistance wire 14, and the other measuring means 9 measures the tem peratureofthewelding pool. The measuring means 8 and 9 are connected via supply leads 10 and 11 to a microprocessor 12, which controls the heating power.The temperature of the resistance wire 14 is set to a maximum value of 280% whereas the welding temperature, in the case of polyethylene, at least, is setatl40to 160#C.
Figure 2 shows the inner surface of the socket 3. A groove 13 is provided in the rim portions of the socket 3, and has the resistance wire laid in it in a meandering configuration; the wire 14 is fixed in it by means of polyethylene film or foil. The measuring means 8 and 9 make use of thermocouples, the thermocouple of the measuring means 8 being fastened to the resistance wire 14, for example by means of clips 15. The thermocouple ofthe measuring means 9, which measures the welding pool temperature, is positioned, between two meanders of the wire 14, in a region at which the lowesttemperature can be expected.This thermocouple is fastened to the socket 3 by means of clamps 1 6which lie outside the groove 13, i.e. outside the welding pool, so that the measuring means 9 wi 11 be secure even at welding temperature and under the application of pressure. Thewelding wire 14 is fixed by means of clamps 17 which are fastened to the socket 3 outside the groove 13, preferably in the region of the curved sections of the wire 14. This manner of fixing is advisable in orderthatthe distance of the measuring means 9 from the resistance wire 14 can be held constant at welding temperature and under the application of pressure.
Figure 3 shows the course of a welding operation by means of three curves, of which the curve C shows the heating power, the curve A shows the wire temperature, i.e. the temperature at the measuring means 8, and the curve B shows thetemperature oftheweld, i.e. atthemeasuring means 9. Time is plotted along the horizontal axis. When the welding transformer7 is switched on, the heating power in creases within a very short time to a maximum value, and is then regulated as required. The rise of the curve A, i.e. ofthe wire temperature, is therefore very steep at first. After the attainment of the maximum wire temperature, this being of the order of 280do, the heating power is restricted, on the basis ofthe temperature values measured at the measuring means 8. The rise ofthe curve B is naturally less steep than the rise of the curve A, since the distance of the measuring means 9 from the adjoining windings ofthe resistance wire 4 is relatively large. After the attainment of the requisite welding temperature, this being of about 1 500C, the heating power is so controlled that the temperature of the measuring means9 is held constantovera period or of about 30 50 seconds. Afterthe completion ofthe welding operation,the microprocessor 12 switches offthewelding transformer 7, and the welds slowly cool.
The invention has been described with reference to a resistance wire laid in a meandering configuration. However, it is also advantageous to make use of a resistance wire laid in a circumferential spiral, in the annular gap between the steel pipe and the socket 3. Two or more resistance wires running alongside one another in a circumferential direction can also be used. The thermocouples measuring the welding pool temperature can in this case be positioned in between two adjacent resistance wires.

Claims (18)

1. A method of producing a socket joint between lengths ofthermally insulated conduitwhich each comprise an inner pipe surrounded by plastics insulation,the inner pipes being welded together, their joint being covered by a plastics socket which surrounds and is welded to the plastics outer layers of the lengths of conduit, one or more resistance wires being introduced in a meandering or spiral configuration between the socket and outer layers, the resistance wire(s) serving (upon a heating current being passed therethrough) to bring into a weldable condition the adjacent surface portions of the socket and outer layers, and the requisite welding together of these surface portions taking place under pressure and heat, wherein the temperature of the resistance wire(s) is continually measured during passage of the heating current, a welding zone temperature between adjacent meanders orturns ofthe resistance wire(s) being measuredatthesametime,thetem- perature of the resistance wire(s) being restricted so as not to exceed a maximum lying marginally below the decomposition or degradation temperature of the adjacent plastics material, and the welding zone temperature specified being utilised as a regulation variable, in that the heating power employed in the welding operation is regulated by reference to the variations in the said welding zone temperature.
2. A method according to claim 1, wherein the welding temperature is kept at a substantially con stantvaluefora period of at least 10seconds.
3. A method according to claim 2, wherein the said period is 30 to 180 seconds.
4. A method according to claim 1, 2 or 3, wherein the resistance wire temperature is controlled by altering the heating power, the heating current being continuously regulated over a range extending from a maximum value down to a value corresponding to theweldingtemperature.
5. A method according to any of claims 1 to 4, wherein the said welding zone temperature which is used as a regulation variable for the heating power is a melttemperature, the heating wire temperature being limited to a maximum value.
6. A method according to any of claims 1 to 5, wherein the regulation of the heating power is obtained by means of a microprocessor.
7. A method according to any of claims 1 to 6, wherein the plastics components undergoing welding are of polyethylene, and the maximum resist ance wire temperature is fixed at 2800C and the weld- ing temperature is fixed at 1400 to 1 600C.
8. Apparatus suitable for use in a method according to claim 1,comprising atransformersuitablefor use in welding, electrical leadswherebythetrans- former's output is (in use) supplied to one or more resistance wires introduced in a meandering or spiral configuration between the socket and outer layers which are to be welded together, a microprocessor which (in use) controls the heating power employed in the welding operation, and electrical leads whereby (in use)the microprocessor receives inputs from two measuring means, these being a first measuring means which (in use) measuresthe temperature of the resistance wire(s) and a second measuring meanswhich (in use) measures a welding zone temperature between adjacent meanders or turns of the resistance wire(s).
9. Apparatus according to claim 8, wherein the said first and second measuring means make use of respective thermocouples.
10. Apparatus according to claim 9, wherein the said first measuring means makes use of a thermocouplesoldered,weldedorotherwisethermallycon ductively connected to the (or a) resistance wire.
11. Apparatus according to claim 9, wherein the said first measuring means makes use of a thermocouple connected to the (or a) resistance wire by means of clips.
12. Apparatus according to any of claims 8to 11, wherein an isolated measured-value amplifier is connected between the said first measuring means and the microprocessor.
13. Apparatus according to any of claims 8 to 12, wherein the said second measuring means makes use of a plurality of thermocouples, which are positioned in a welding pool.
14. Apparatus according to any of claims 8to 13, wherein the said welding zone temperature is measured by means of at least one thermocouple fastened outside the respective welding zone.
15. Apparatus according to any of claims 8 to 14, wherein a resistance wire meander surrounds the said second measuring means and is fixed at at least three points by means offastening elements positioned outside the respective welding zone.
16. Apparatus according to claim 15,whereinthe at least three fixing points specified occur in these gion ofthe curved sections ofthe resistance wire.
17. A method according to claim 1, substantially as described with reference to the accompanying drawing.
18. Apparatus according to claim 8, substantially as described with reference to the accompanying drawing.
GB8713118A 1986-06-05 1987-06-04 Method of producing a socket joint for a thermally insulated conduit Withdrawn GB2191146A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE3619006 1986-06-05

Publications (2)

Publication Number Publication Date
GB8713118D0 GB8713118D0 (en) 1987-07-08
GB2191146A true GB2191146A (en) 1987-12-09

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GB8713118A Withdrawn GB2191146A (en) 1986-06-05 1987-06-04 Method of producing a socket joint for a thermally insulated conduit

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JP (1) JPS62292419A (en)
KR (1) KR880000219A (en)
CN (1) CN87102675A (en)
DK (1) DK291187A (en)
FI (1) FI872513A (en)
FR (1) FR2607057A1 (en)
GB (1) GB2191146A (en)
IT (1) IT1206014B (en)
NL (1) NL8701310A (en)
SE (1) SE8702326L (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995016557A2 (en) * 1993-12-15 1995-06-22 Tokushu, Kogyo Kabushikigaisha Electrofusion fastening apparatus
FR2725658A1 (en) * 1994-09-26 1996-04-19 Toa Kokyu Tugitebarubu Seizo C Automatic control of melting between thermoplastic products
WO1997001433A1 (en) * 1995-06-28 1997-01-16 Raymond Allan Goldsmid Element for fusion welding plastics

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE529741C2 (en) * 2005-01-17 2007-11-13 Sandvik Intellectual Property Procedure for thermal insulation of weld joint and sleeve therefor
SE534975C2 (en) * 2009-10-16 2012-03-06 Tsc Innovation Ab Method and apparatus for installing and repairing insulated pipe lines

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995016557A2 (en) * 1993-12-15 1995-06-22 Tokushu, Kogyo Kabushikigaisha Electrofusion fastening apparatus
WO1995016557A3 (en) * 1993-12-15 1996-02-29 Tokushu Kogyo Kabushikigaisha Electrofusion fastening apparatus
FR2725658A1 (en) * 1994-09-26 1996-04-19 Toa Kokyu Tugitebarubu Seizo C Automatic control of melting between thermoplastic products
WO1997001433A1 (en) * 1995-06-28 1997-01-16 Raymond Allan Goldsmid Element for fusion welding plastics
EP0927097A1 (en) * 1995-06-28 1999-07-07 Raymond Allan Goldsmid Element for fusion welding plastics
EP0927097A4 (en) * 1995-06-28 1999-08-11

Also Published As

Publication number Publication date
CN87102675A (en) 1987-12-16
FR2607057A1 (en) 1988-05-27
DK291187A (en) 1987-12-06
IT8748019A0 (en) 1987-06-04
SE8702326L (en) 1987-12-06
FI872513A (en) 1987-12-06
SE8702326D0 (en) 1987-06-04
KR880000219A (en) 1988-03-24
FI872513A0 (en) 1987-06-04
GB8713118D0 (en) 1987-07-08
DK291187D0 (en) 1987-06-04
NL8701310A (en) 1988-01-04
IT1206014B (en) 1989-04-05
JPS62292419A (en) 1987-12-19

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