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
  • B23K9/00—Arc welding or cutting
  • B23K9/02—Seam welding; Backing means; Inserts
  • B23K9/028—Seam welding; Backing means; Inserts for curved planar seams
  • B23K9/0282—Seam welding; Backing means; Inserts for curved planar seams for welding tube sections
  • B23K9/0286—Seam welding; Backing means; Inserts for curved planar seams for welding tube sections with an electrode moving around the fixed tube during the welding operation
• • 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
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/346—Working by laser beam, e.g. welding, cutting or boring in combination with welding or cutting covered by groups B23K5/00 - B23K25/00, e.g. in combination with resistance welding
  • B23K26/348—Working by laser beam, e.g. welding, cutting or boring in combination with welding or cutting covered by groups B23K5/00 - B23K25/00, e.g. in combination with resistance welding in combination with arc heating, e.g. TIG [tungsten inert gas], MIG [metal inert gas] or plasma welding
• • 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
  • B23K33/00—Specially-profiled edge portions of workpieces for making soldering or welding connections; Filling the seams formed thereby
  • B23K33/004—Filling of continuous seams
  • B23K33/006—Filling of continuous seams for cylindrical workpieces
• • 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
  • B23K2101/10—Pipe-lines
• • 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
  • B23K2103/00—Materials to be soldered, welded or cut
  • B23K2103/02—Iron or ferrous alloys
  • B23K2103/04—Steel or steel alloys
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T83/00—Cutting
  • Y10T83/04—Processes

Definitions

• the present invention relates to a method of machining metal conduits 5 which end to end with identical conduits to be welded form pipeline type metal pipes for the transport of gas, oil and a method of welding metal conduits Machined according to the machining process.
• hybrid laser welding process In order to achieve the solder joint reliably, it has been proposed to use an electric arc assisted laser welding process, hereinafter referred to as a hybrid laser welding process.
• a hybrid laser welding process In order to achieve the solder joint reliably, it has been proposed to use an electric arc assisted laser welding process, hereinafter referred to as a hybrid laser welding process.
• the various hybrid laser welding processes and devices for their implementation have many disadvantages. 0
• the electric arc has a low power of interpenetration in the thickness of the bead, it therefore results in a dilution of the non-homogeneous filler metal through the thickness of the melt, the filler metal remaining mainly in the outer part of the chamfer.
• US-A-4213555 discloses a welding method in which it is proposed for tubes having a thickness greater than 12 mm to make the chamfer as having from the base a first inclined slope of 25 ° followed by a second slope of 5 ° with respect to the joint plane. Such a chamfer does not have a heel. However, if a hybrid laser welding process with a chamfer of such a shape is used, there is a risk of chamfer penetrations, collapse of the melt or the risk of a stepped joint profile if there is one. misalignment of the two tubes.
• TGF GAY &J.SPENCE's Rational Welding Design 1982, Butterwoths & Co (Publishers) Ltd, Norwich, Norfolk, UK, page 71, discloses butt welding of thickness less than 20 mm, the end of which has a profile with a straight part followed by an inclined part so as to form a chamfer with heel and outer case in V of slope of 30 ° to 40 ° which has the drawbacks mentioned above.
• This same document proposes to produce, for ducts with a thickness greater than 20 mm, a profile having a straight part and a section inclined from 10 to 15 °, connected by a curved section making it possible to obtain a U-shaped bevel, this curved section forms well a chamfer n U because it is not tangent to the inclined section.
• a U-shaped chamfer is also described in "Welder's Troubleshooting Guide," 1983, Reston Publishing Company, I, Reston, Virginia, USA, pages 55-56.
• FR 985 513 proposes a duct profile comprising a straight portion and an inclined portion connected by a flat portion and a curved portion, the chamfer thus formed is U-shaped flat bottom, there is then a problem of centering the laser beam when laser welding with such a chamfer.
• a problem arises as soon as the thickness of the ends to be assembled increases and a chamfer too wide is difficult to fulfill with automated arc welding equipment.
• V and U bevels have also been proposed, such as those described in JP 56151192.
• the disadvantages of the V and U chamfer are found.
• the object of the invention is to overcome these drawbacks by proposing a method of machining metal conduits, which, end-to-end to be welded with identical conduits, forms a pipeline-type pipe, the machined ends forming together a chamfer of new form for high-speed welding of the penetration pass, in particular by a hybrid laser welding process.
• the subject of the invention is a method for machining the ends of a metal duct intended to form, when it is placed end to end with identical ducts and welded to them, a pipeline-type duct for creating at the level of the joint plane with another identical duct a V-shaped chamfer, characterized in that the ends of the duct are cut so that the profile of each end has at least a first straight section, at the inner edge, intended for forming a portion of the V-chamfer heel and an arcuate section connecting said straight section of the profile to a rectilinear section inclined relative to the cross section of this profile, the outer edge of the tubular piece.
• the cross-section of the end profile of a duct abuts against the cross-section of the end profile of the duct.
• the other leads to form the heel of a V-shaped chamfer, whose tip is slightly curved on either side of the joint plane due to the two arcuate sections and the V-shaped chamfer has an opening defined by the end of inclined sections.
• the arcuate section is defined to be tangent to the inclined rectilinear section and the inclination angle ⁇ of the inclined section is preferably in the range of 15 ° to 45 ° relative to the cross section of the end profile, coincident with the joint plane, so that the width of the chamfer at its open end is at most 10 mm.
• a duct thus machined preferably has a thickness of at most 10 mm and the cross section of the profile has a minimum thickness of 2 mm to ensure reproducibility of machining and so that the heel of the chamfer formed can not be pierced during a penetration pass by a laser beam for example.
• the profile may furthermore have a second section inclined at an angle ⁇ with respect to the section right of the end profile of the duct, said angle ⁇ being less than the angle ⁇ , connected to the first inclined section by a second arcuate section, so as to always maintain the open width of the chamfer less than 14 mm.
• the second arc is chosen to be tangent to the two inclined sections.
• Ducts obtained according to the machining method of the invention are particularly advantageous in the context of using a hybrid laser welding process in which the penetration pass is achieved from the outside by creating a single melt under the simultaneous action of at least one laser beam transmitted by optical fiber and at least one gas-shielded electric arc generated from a fuse electrode.
• the cross section of the end profile of the conduit then has a maximum thickness equivalent to 2 mm + a value corresponding to the power in kW of the laser used.
• This allows a high welding speed of several meters per minute during the penetration phase while using a laser power of only a few kW and which can in particular be less than 4 kW, which is economically advantageous.
• the point of impact of the electric arc is close to the focal point of the laser beam, the interval between the two being called “offset", this interval being -5 to 5 mm with respect to the point of contact. focusing of the laser beam.
• the arcuate parts in the bottom of the chamfer confer a tolerance on the centering of the laser beam, thus ensuring increased compactness by less sensitivity to the risk of lack of penetration.
• the opening in the upper part of the first inclined sections of the end profiles of the conduits does not exceed 10 mm, which makes it possible not to have an opening of chamfer too wide in the part corresponding to the part of the welded joint by the laser process and further allows to obtain a high deposited metal height even at high speed. Likewise, this opening is always greater than 3 mm in order to avoid problems of hot cracking.
• a duct obtained according to the machining method of the invention allows the implementation of a hybrid laser welding process as mentioned above with good productivity while limiting the risk of lack of lateral fusion due to low energy welding used.
• the position of the focusing point of the laser beam can be adjusted independently of one another.
• the interval between the focusing point of the laser beam and the position of the point of impact of the electric arc and the angular position of the electric arc welding torch such as a MIG torch relative to the laser beam, the MIG torch being angularly offset to the laser beam.
• the focus point of the laser beam is adjustable within a range of +/- 5mm above or below the chamfer heel, the interval between the focus point and the point of impact of the arc.
• the electric range may vary in the range of -5 mm to +5 mm on either side of the laser focus point and the angular range in which the MIG torch varies with respect to the laser beam is 5 ° to 45 °.
• the profile comprises an inclined section or double section inclined with the angle ⁇ of the first section greater than the angle ⁇ of the second section, the aperture of the chamfer remaining limited to 14 mm maximum to allow the rest of the welding with the electric arc method with fuse wire in narrow chamfer configuration whatever the configuration of the welding head (mono, multi torches).
• arcuate sections at the bottom of the chamfer allows a better interpenetration of the electric arc in the thickness of the heel, one thus obtains a dilution of the more homogeneous filler metal and thus mechanical characteristics also more homogeneous.
• the left-hand part of the figure corresponds to a duct 1 having a thickness hi and the right-hand part of the figure corresponds to a duct 2 having a thickness less than h 2 to hi
• the cross section 3 of the end profile of the two ducts 1 and 2 has a height h 3 of 2 mm.
• the cross section is followed by a circular arc section 4 of identical radius Ri on the left and right side of the single figure.
• This arcuate section 4 serves as a connection between the straight section 3 and a rectilinear section inclined with respect to the joint plane P.
• the angle of inclination ⁇ is in the example represented by 25 °.
• the inclined section 5 is followed by a second circular arc section of radius R 2 which connects said inclined section 5 to a second inclined section 6 or 6 '.
• the inclination angle ⁇ of this second inclined section relative to the joint plane P is less than ⁇ and in the example represented equal to 5 °.
• the width U of the opening of the chamfer is at most 10 mm in the example shown in the right part of the single figure and the width L is at most 14 mm in the example of the left part.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Mechanical Engineering (AREA)
• Optics & Photonics (AREA)
• Plasma & Fusion (AREA)
• Laser Beam Processing (AREA)
• Butt Welding And Welding Of Specific Article (AREA)

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• 2005
  • 2005-06-02 FR FR0505604A patent/FR2886563B1/fr not_active Expired - Fee Related
• 2006
  • 2006-06-02 WO PCT/FR2006/001259 patent/WO2006129025A1/fr active Application Filing
  • 2006-06-02 US US11/916,282 patent/US20090133773A1/en not_active Abandoned
  • 2006-06-02 CA CA002610488A patent/CA2610488A1/fr not_active Abandoned
  • 2006-06-02 RU RU2007147684A patent/RU2407616C2/ru not_active IP Right Cessation
  • 2006-06-02 EP EP06764726A patent/EP1907162A1/de not_active Withdrawn

Non-Patent Citations (1)

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