US20060131299A1 - Electric induction impeder - Google Patents

Electric induction impeder Download PDF

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Publication number
US20060131299A1
US20060131299A1 US11/303,694 US30369405A US2006131299A1 US 20060131299 A1 US20060131299 A1 US 20060131299A1 US 30369405 A US30369405 A US 30369405A US 2006131299 A1 US2006131299 A1 US 2006131299A1
Authority
US
United States
Prior art keywords
impeder
enclosure
passage
cooling medium
magnetic material
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.)
Abandoned
Application number
US11/303,694
Other languages
English (en)
Inventor
Paul Scott
Michael Nallen
Oleg Fishman
John Mortimer
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.)
Inductotherm Corp
Original Assignee
Inductotherm 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
Application filed by Inductotherm Corp filed Critical Inductotherm Corp
Priority to US11/303,694 priority Critical patent/US20060131299A1/en
Assigned to INDUCTOTHERM CORP. reassignment INDUCTOTHERM CORP. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FISHMAN, CLEG S., MORTIMER, JOHN H., NALLEN, MICHAEL A., SCOTT, PAUL F.
Publication of US20060131299A1 publication Critical patent/US20060131299A1/en
Priority to US12/471,451 priority patent/US8263915B2/en
Priority to US13/608,188 priority patent/US9073145B2/en
Priority to US13/608,080 priority patent/US8921745B2/en
Abandoned legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K13/00—Welding by high-frequency current heating
    • B23K13/01—Welding by high-frequency current heating by induction heating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K13/00—Welding by high-frequency current heating
    • B23K13/01—Welding by high-frequency current heating by induction heating
    • B23K13/02—Seam welding
    • B23K13/025—Seam welding for tubes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K2101/00—Articles made by soldering, welding or cutting
    • B23K2101/04—Tubular or hollow articles
    • B23K2101/06—Tubes

Definitions

  • the present invention relates to impeders that can be used in electric induction welding processes to form, for example, metal pipe or tubing from strip stock.
  • Impeders are used in high frequency welded pipe and tube fabrication processes. They are one or more pieces of ferrite, or other magnetic material, that is placed inside a pipe or tube within the weld area. This magnetic material accomplishes two things. It increases the electrical impedance of the inside current path of the tube, forcing the current to flow on the vee edges of the tube instead. It is this current that heats the vee edges prior to forging them together in the weld box. Secondly, it creates a low magnetic reluctance path inside the tube between the apex of the weld vee and the rear of the tube. The lower reluctance path becomes the preferred path for the magnetic field.
  • the magnetic field that the impeder carries causes losses in the ferrite due to its finite resistivity and its coercivity. These losses heat the ferrite, and if heat is not removed through proper cooling, the ferrite's Curie temperature (the temperature at which a material looses its magnetic properties) can be exceeded or the binder that holds the ferrite material together can disintegrate.
  • Ferrite is a brittle material and mechanical shock encountered during the tube fabrication processes can cause it to break into multiple pieces. When this happens the effective magnetic properties are greatly reduced.
  • the ferrite is usually enclosed in a jacket generally made from a fiberglass type material. This helps protect the ferrite from mechanical shock and provides a means for channeling cooling water to the ferrite.
  • the diameter of the ferrite When fabricating smaller diameter tube, the diameter of the ferrite must be as large as possible so that the impeder does not magnetically saturate. This results in tight clearances between the ferrite and the casing. Thus the cooling water must not contain contaminants that can plug the coolant passage between the ferrite and its casing. When this happens, the ferrite will fail almost immediately due to local over-heating. Temporary interruptions in the coolant supply can cause steam to develop inside the impeder casing. When this happens, the ferrite can temporarily exceed its Curie temperature and this can result in a section of “cold” or paste weld in the tube.
  • One object of the present invention is an impeder that does not require internal cooling. Another object of the present invention is to provide an impeder with internal cooling that operates with improved efficiency.
  • the present invention is apparatus for, and method of, electric induction welding with an impeder.
  • the impeder is formed from a high temperature impeder element disposed in a high temperature enclosure.
  • the impeder element may be a plurality of solid wires formed from permendur, each of which is electrically isolated from the other wires.
  • the high temperature enclosure may be formed from a suitable ceramic composition.
  • Internal cooling if provided, may be via a closed or open cooling system.
  • the impeder element may be a ferrite, or a rolled magnetically conductive sheet.
  • FIG. 1 ( a ) is a longitudinal cross sectional view of one example of an impeder of the present invention that does not require internal cooling.
  • FIG. 1 ( b ) is a cross sectional view of the impeder in FIG. 1 ( a ) along the line A-A.
  • FIG. 2 ( a ) is a longitudinal cross sectional view of one example of an impeder of the present invention with internal cooling.
  • FIG. 2 ( b ) is a cross sectional view of the impeder in FIG. 2 ( a ) along the line B-B.
  • FIG. 3 ( a ) is a longitudinal cross sectional view of another example of an impeder of the present invention with internal cooling.
  • FIG. 3 ( b ) is a cross sectional view of the impeder in FIG. 3 ( a ) along the line C-C.
  • FIG. 4 ( a ) is a longitudinal cross sectional view of another example of an impeder of the present invention with internal cooling.
  • FIG. 4 ( b ) is a cross sectional view of the impeder in FIG. 4 ( a ) along the line D-D.
  • FIG. 5 is a cross sectional simplified illustration of an arrangement for an induction welding process wherein an impeder of the present invention is used.
  • FIG. 1 ( a ) and FIG. 1 ( b ) a first example of the impeder 10 of the present invention.
  • the impeder element 12 comprises a bundle of high temperature solid wires 14 substantially surrounded by a high temperature enclosure 16 .
  • the high temperature solid wires are formed from a suitable type of high Curie temperature magnetic material, such as but not limited to, a class of iron-cobalt alloys known as permendur to form a cylindrical bundle.
  • the term “high Curie temperature” as used herein generally refers to a Curie temperature of approximately 235° C. or higher.
  • Each wire is electrically isolated from each of the other wires by means of a suitable insulation that may be formed by an oxidation process on the surface of each wire, or by any other suitable method.
  • the term “high temperature enclosure” as used herein generally refers to an enclosure material capable of withstanding approximately 200° C., or higher, depending upon a particular application, and may be formed from a suitable heat resistant material such as a ceramic composition.
  • a suitable heat resistant material such as a ceramic composition.
  • One non-limiting type of ceramic composition that may be used for the enclosure is a silicon-aluminum-oxynitride composition known as sialon.
  • a synthetic high temperature polymer such as a polyaramid polyparaphenylene terephthalamide composition, for example, in the form of a KEVLAR tape, may be used to form the enclosure.
  • the enclosure may be cast around the plurality of wires used in impeder 10 . While the impeder in FIG. 1 ( a ) and FIG. 1 ( b ) has a generally overall cylindrical shape, other shapes are suitable depending upon a particular application.
  • the term “wire” as used herein generally refers to a magnetically conductive material, which may be of any cross sectional shape, and have with a cross section, typically (but not limited to) between 8 and 24 American Wire Gauge (AWG). Wires of different compositions may be used in other examples of the inventions, and the enclosure may be formed from multiple parts of different high temperature material.
  • FIG. 2 ( a ) and FIG. 2 ( b ) illustrate a second example of the impeder 20 of the present invention.
  • the impeder element 22 comprises a cylindrical ring of high temperature solid wires 24 that is enclosed in a high temperature enclosure 26 .
  • Center passage 28 is formed in the cylindrical ring of wires and provides a flow path for a cooling medium, such as but not limited to air, water or liquid nitrogen. Flow is from the INLET to the OUTLET as illustrated by the arrows in FIG. 2 ( a ).
  • a venturi element 21 can be optionally placed at the inlet of the center passage to enhance the cooling effect of the cooling medium.
  • the impeder 20 in FIG. 2 ( a ) and FIG. 2 ( b ) has a generally overall cylindrical shape, other shapes are suitable depending upon a particular application.
  • the ring of high temperature wires may be of rectangular shape in cross section with a suitable passage formed with the plurality of wires for the flow of a cooling medium. More than one inlet or outlet ports may be provided depending upon a particular application. In other examples of the invention more than one passage may be provided through the impeder element.
  • FIG. 3 ( a ) and FIG. 3 ( b ) illustrate a third example of the impeder 30 of the present invention wherein a closed loop cooling system is used.
  • the impeder element 32 comprises a magnetic material that is enclosed within a high temperature enclosure 36 .
  • the magnetic material is in the shape of an open cylinder.
  • the magnetic material may be any suitable magnetic material such as a ferrite or the high temperature wires described above, and the high temperature enclosure may be a ceramic composition as described above.
  • Center passage 38 provides a flow path for a cooling medium through the impeder from the inlet, and can generally be referred to as a coolant entry passage. More than one coolant entry passages may be provided in other examples of the invention.
  • Annular region 39 forms a space between the inner wall of the enclosure and the magnetic material to provide a flow path around the impeder to the outlet, and can generally be referred to as a coolant exit passage. Coolant flow through the impeder is as illustrated by the arrows in FIG. 3 ( a ).
  • the coolant exit passage may be provided with one or more passage walls that selectively direct flow around the space between the inner wall of the enclosure and the magnetic material. More than one inlet or outlet ports may be provided depending upon a particular application. As in the second example of the invention a venturi element can be optionally placed at the inlet to enhance cooling around the impeder.
  • FIG. 4 ( a ) and FIG. 4 ( b ) illustrate a fourth example of the impeder 40 of the present invention which is similar to the third example above except that the cooling medium is provided in an open cooling system wherein the cooling medium enters at the inlet and flows around impeder element 42 through annular passage 49 to exit out the outlet as indicated by the arrows in FIG. 4 ( a ).
  • an open loop system is used when the cooling medium can also serve as the mill coolant, which is used to wash away oils, oxides, slivers, and dirt generated during mill processes.
  • the impeder element may be in the shape of an open ring and the cooling medium will flow through the center passage of the ring.
  • Impeder element 42 may be any suitable magnetic material such as a ferrite or the high temperature wires described above, and high temperature enclosure 46 may be a ceramic composition as described above.
  • the impeder element may be a sheet of high Curie temperature magnetic material, such as but not limited to permendur, that is rolled to form a generally cylindrical shape. Adjacent surfaces of the rolled material are electrically insulated from each other by any suitable method, including but not limited to an oxidation process.
  • the sheet can be rolled with a bobbin or one or more removal spindles to form one or more coolant passages within the impeder element. Suitable but not limiting thickness of the sheet is in the range of the diameters stated above for the high temperature wires used in other examples of the invention.
  • FIG. 5 illustrates one example of use of an impeder of the present invention in an electric induction welding process.
  • Stock material 90 which may be a metal sheet, is driven through weld box 92 in the direction indicated by the arrow to bring opposing edges of the stock material together.
  • AC current flowing through induction coil 94 which surrounds the stock material, creates a magnetic field that couples with the stock material. Induced currents in the stock material weld the opposing edges of the stock material together as they pass through the weld box to form a product 96 , such as a tube or pipe.
  • An impeder of the present invention for example impeder 10 shown in FIG. 1 ( a ) and FIG. 1 ( b ), is inserted into the stock material generally in the region shown in FIG. 5 .
  • a coolant with a high heat capacity such as an oil-based coolant can be used to reduce the flow and pressure requirements for the cooling system.
  • a return flow type impeder casing design such as that illustrated in FIG. 3 ( a ) and FIG. 3 ( b ) with pumps at both the inlet and outlet would allow the outlet pressure to be below atmospheric. Attaching a short hose through a one-way valve to the outlet side of the impeder would allow the system to remove any excess mill coolant from inside the welded tube. Excess mill coolant inside the tube can cause steam blowback through the weld vee, if it is heated by a subsequent steam annealing process.
  • an advanced filtration system can be used to remove all contaminants from the impeder coolant and thereby eliminate any cooling passage clogging problem.
  • a refrigeration system can be used to remove the heat from the coolant and control its inlet temperature at just below the optimal temperature that maximizes the magnetic properties of the impeder.
  • thermalally designed texture refers to any method of configuring the surface wall or boundary of the magnetic material, when that wall or boundary is used as a boundary for the cooling medium passage, to reduce laminar boundary flow conditions from those existing when the wall or boundary is substantially smooth, including application of a boundary wall texturing material over the magnetic material.
  • an optional inside cushioning liner can be disposed between the high temperature enclosure and the impeder to reduce shock transfer to the impeder material, which can extend the life of the impeder.
  • the inside of the casing or the liner can be molded with cooling passages and/or a special texture to create turbulence in the coolant and thereby increasing the heat transfer between the ferrite and the coolant.
  • the ferrite composition can be optimized for high Curie temperature, and low coercivity and resistive losses to integrate it with the cooling system and coolant employed.
  • High temperature binder possibly ceramic based, can be used to prevent binder disintegration.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Induction Heating (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Connections Effected By Soldering, Adhesion, Or Permanent Deformation (AREA)
  • Manufacturing Of Electrical Connectors (AREA)
  • Transformer Cooling (AREA)
  • Soft Magnetic Materials (AREA)
US11/303,694 2004-12-20 2005-12-16 Electric induction impeder Abandoned US20060131299A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US11/303,694 US20060131299A1 (en) 2004-12-20 2005-12-16 Electric induction impeder
US12/471,451 US8263915B2 (en) 2004-12-20 2009-05-25 Electric induction impeder
US13/608,188 US9073145B2 (en) 2004-12-20 2012-09-10 Electric induction impeder
US13/608,080 US8921745B2 (en) 2004-12-20 2012-09-10 Electric induction impeder

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US63759004P 2004-12-20 2004-12-20
US11/303,694 US20060131299A1 (en) 2004-12-20 2005-12-16 Electric induction impeder

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US12/471,451 Division US8263915B2 (en) 2004-12-20 2009-05-25 Electric induction impeder

Publications (1)

Publication Number Publication Date
US20060131299A1 true US20060131299A1 (en) 2006-06-22

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Family Applications (4)

Application Number Title Priority Date Filing Date
US11/303,694 Abandoned US20060131299A1 (en) 2004-12-20 2005-12-16 Electric induction impeder
US12/471,451 Active 2026-11-01 US8263915B2 (en) 2004-12-20 2009-05-25 Electric induction impeder
US13/608,080 Expired - Fee Related US8921745B2 (en) 2004-12-20 2012-09-10 Electric induction impeder
US13/608,188 Expired - Fee Related US9073145B2 (en) 2004-12-20 2012-09-10 Electric induction impeder

Family Applications After (3)

Application Number Title Priority Date Filing Date
US12/471,451 Active 2026-11-01 US8263915B2 (en) 2004-12-20 2009-05-25 Electric induction impeder
US13/608,080 Expired - Fee Related US8921745B2 (en) 2004-12-20 2012-09-10 Electric induction impeder
US13/608,188 Expired - Fee Related US9073145B2 (en) 2004-12-20 2012-09-10 Electric induction impeder

Country Status (7)

Country Link
US (4) US20060131299A1 (de)
EP (1) EP1827748A4 (de)
KR (1) KR101179486B1 (de)
CN (1) CN101084084A (de)
RU (1) RU2007127688A (de)
WO (1) WO2006068967A2 (de)
ZA (1) ZA200705521B (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2478989A4 (de) * 2009-09-16 2017-06-21 Nippon Steel & Sumitomo Metal Corporation Schweissvorrichtung zur herstellung eines widerstandsgeschweissten rohrs
CN108555427A (zh) * 2018-06-14 2018-09-21 山东汉尚新型材料有限公司 一种用于小直径厚壁管的高频焊接装置

Families Citing this family (4)

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Publication number Priority date Publication date Assignee Title
DE102013006328A1 (de) * 2013-04-11 2014-10-16 Daimler Ag Halteanordnung eines Stoßfängers an einem Bauelement eines Personenkraftwagens sowie Leuchteinheit für einen Personenkraftwagen
CN105710523B (zh) * 2016-02-14 2018-05-01 汕头轻工机械厂有限公司 一种跑道型密绕式电磁感应器
JP6834723B2 (ja) * 2017-04-07 2021-02-24 日本製鉄株式会社 電縫管溶接装置
EP4349519A1 (de) 2022-10-03 2024-04-10 Societa' Italiana Acetilene & Derivati S.I.A.D. S.p.A. in breve S.I.A.D. S.p.A. Stickstoffkühlsystemvorrichtung für hochfrequenzschweissverfahren mit impedanzmesser

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US4056743A (en) * 1973-07-30 1977-11-01 Horstmann Clifford Magnetics Ltd. Oscillating reed electric motors
US3987362A (en) * 1973-11-12 1976-10-19 United Kingdom Atomic Energy Authority Sensors
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US4818833A (en) * 1987-12-21 1989-04-04 United Technologies Corporation Apparatus for radiantly heating blade tips
US5760532A (en) * 1991-12-26 1998-06-02 Ngk Spark Plug Co., Ltd. Sintered ceramic body for a spark plug
US6534891B2 (en) * 1992-01-15 2003-03-18 General Electric Company High speed induction motor rotor and method of fabrication
US5701040A (en) * 1992-11-03 1997-12-23 British Technology Group Limited Magnet arrangement, and drive device and cooling apparatus incorporating same
US6949728B2 (en) * 2001-08-02 2005-09-27 Jfe Steel Corporation Impeder for manufacturing welded pipe

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2478989A4 (de) * 2009-09-16 2017-06-21 Nippon Steel & Sumitomo Metal Corporation Schweissvorrichtung zur herstellung eines widerstandsgeschweissten rohrs
US10307808B2 (en) 2009-09-16 2019-06-04 Nippon Steel & Sumitomo Metal Corporation Electric-resistance-welded pipe welding apparatus
CN108555427A (zh) * 2018-06-14 2018-09-21 山东汉尚新型材料有限公司 一种用于小直径厚壁管的高频焊接装置

Also Published As

Publication number Publication date
KR101179486B1 (ko) 2012-09-07
US20130008888A1 (en) 2013-01-10
ZA200705521B (en) 2016-07-27
US8263915B2 (en) 2012-09-11
US20090230121A1 (en) 2009-09-17
KR20070088788A (ko) 2007-08-29
EP1827748A4 (de) 2009-04-15
RU2007127688A (ru) 2009-01-27
EP1827748A2 (de) 2007-09-05
WO2006068967A3 (en) 2007-01-25
WO2006068967A2 (en) 2006-06-29
US20130001219A1 (en) 2013-01-03
US8921745B2 (en) 2014-12-30
US9073145B2 (en) 2015-07-07
CN101084084A (zh) 2007-12-05

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Owner name: INDUCTOTHERM CORP., NEW JERSEY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SCOTT, PAUL F.;NALLEN, MICHAEL A.;FISHMAN, CLEG S.;AND OTHERS;REEL/FRAME:017389/0837;SIGNING DATES FROM 20051213 TO 20051214

STCB Information on status: application discontinuation

Free format text: EXPRESSLY ABANDONED -- DURING EXAMINATION