Showing papers on "Butt welding published in 1998"

Rapid prototyping of metal parts by three-dimensional welding

Abstract: Three-dimensional welding has the ability to produce strong, fully dense metal parts in layers. Adaptation of a weld cladding technique has enabled the production of parts wider than normal...

Friction welding metal components

Abstract: A method of forming a structural airframe component for an aircraft and an airframe structural component are provided. The method includes placing at least two components (1, 2) in abutting relationship with each other and joining them together by friction stir butt welding (3), and the structural airframe component comprises a component manufactured according to the method of the invention.

Friction plug welding

Abstract: Friction plug welding (FPW) usage is advantageous for friction stir welding (FSW) hole close-outs and weld repairs in 2195 Al—Cu—Li fusion or friction stir welds. Current fusion welding methods of Al—Cu—Li have produced welds containing varied defects. These areas are found by non-destructive examination both after welding and after proof testing. Current techniques for repairing typically small (<0.25″) defects weaken the weldment, rely heavily on welders' skill, and are costly. Friction plug welding repairs increase strength, ductility and resistance to cracking over initial weld quality, without requiring much time or operator skill. Friction plug welding while pulling the plug is advantageous because all hardware for performing the weld can be placed on one side of the workpiece.

Method and apparatus for friction stir welding

Abstract: The invention concerns a friction stir welding method according to which the workpieces (2, 3) to be welded are positioned on a work-table (7) and by means of clamping means (5, 6) clamped to one another and/or to the work-table during the welding. A rotating welding means (12, 13) is arranged to move along a joint between the workpieces while being pressed against said workpieces during the welding. Additional heat is supplied to the joint prior to and/or during the welding operation, in excess of the frictional heat generated in the joint from the rotation of the welding means and of any other heat that may be supplied to the joint in any other manner by the welding means. The invention likewise concerns an apparatus for friction stir welding, comprising a heating element (70) for supply of additional heat to the joint prior to and/or during the welding operation, in excess of the frictional heat generated in the joint from the rotation of the welding means and of any other heat that may be supplied to the joint in any other manner by the welding means.

Computerized simulation of laser beam weld formation comprising joint gaps

Abstract: A model of laser beam weld shape formation which comprises butt and overlap joints with a small gap between the parts to be joined is considered. It is the goal of the simulation to predict the effect of technological parameters on the reinforcement or concavity of the weld or weld root and on the area of the load-carrying cross section which controls the strength of the joint. The model is based on the equations of energy transport and of equilibrium at the free surfaces for balancing vapour pressure, capillary pressure and a correction term. The correction term allows balancing the metal volume taking into account thermal expansion and shrinkage during welding and the gap width between the parts to be joined. Verification of the simulation results for gap widths in the range 0-0.2 mm shows that the model corresponds sufficiently well to the experimental data when considering laser beam weld formation in butt and overlap joints of 1.5-6.0 mm sheet thickness. The model explains the weld concavity occurring with gaps in butt and overlap joints, the increase in penetration depth for butt welds with gaps and the widening of the molten zone near the gap in overlap joints.

Ultrasonic welding device and method, and a magnetic tape cartridge reel welding device and method

Abstract: It is an object of the invention to provide a method and a device which can manufacture, by ultrasonic welding, a reel for use in a magnetic tape cartridge with an improved yield rate, while not only restricting the deformation of workpieces but also preventing the products from varying in quality. At least one of the amplitude of an oscillator power source 80 and pressure to be applied to workpieces in an ultrasonic welding operation are set high in the early stage of the ultrasonic welding operation and are then switched into lower levels in the middle of the ultrasonic welding operation when the workpieces, that is, upper and lower reels 4 and 5, begin to melt together.

Conductive heat resistance seam welding

Abstract: A welding arrangement (10) consists of first and second parts to be welded (4a, 4b) with a portion of the first part and a portion of the second part juxtaposed to form a weld zone (8a, 8b). An electrically-conductive sheet (2) with a higher melting temperature than a a melting temperature of the first pan (4a) and a melting temperature of the second part (4b) is placed over the weld zone (8a, 8b). A first electrode (12) is placed in contact with the electrically conductive sheet material (2) and a second electrode (14) is positioned and aligned with the first electrode (12) to heat conductively the weld zone (8a, 8b) with an electrical current. For the butt weld configuration (10), a second electrically conductive sheet (6) is placed between the second electrode (14) and the weld zone (8a, 8b).

Measurement of the Temperature Rise at the Welding Surface of Different Metal Specimens Joined by a 15 kHz Ultrasonic Butt Welding System

Abstract: The temperature rise at the welding surface of different metal specimens joined by a 15 kHz ultrasonic butt welding system is studied. The welded zone of the ultrasonic welding is limited to a very thin area and a clear melted structure cannot be observed and also the temperature rise at the welding surface cannot obtained by clearly measured. Temperature rises at the welding surfaces of different metal specimens are measured directly by the thermoelectromotive force between them, using a system with a small time constant. The temperature rises are measured using a 15 kHz ultrasonic butt welding with which it is possible to join the welding specimens directly end to end. Aluminum, copper and steel plates of 6 mm thickness were successfully joined end to end. The measured temperature rise rate is very high at the initial welding stage and decreases, or the temperature saturates, as the welding process progresses and the welding strength increases.

Method and device for laser butt welding of metallic tube

Abstract: PROBLEM TO BE SOLVED: To suppress heat strain form welding and to obtain a sound weld zone in which strength and toughness are improved by carrying out tack welding and normal welding with a specific penetration depth, before piercing welding, simultaneously at a position oppositely facing on the circumference and giving a post heat treatment to the weld zone. SOLUTION: After tack welding is performed on an abutting part with a penetration depth of 10-50% of a tube thickness, normal welding is performed on the abutting part with the penetration depth of 100% of the tube thickness, with a post heat treatment given to the weld zone. For this purpose, a laser beam LB from a laser generator 1 La (1Lb similarly) is transmitted in a first and an extendable/contractible second laser beam guide 7a, 8a through a fixed laser beam guide 20a, a first and a second rotary deflection devices 2a, 3a. Further, through a third rotary deflection device 4a, it is made incident on a laser beam converging optical system 5b on a truck 51a travelling along a ring-shaped guide rail 6. The center of the guide rail 6 is nearly coincident with that of a metallic tube 1a, 1b, with two trucks 51a, 51b made to run along the circumference at an interval of 180 deg..

Method and apparatus for controlling forging force during flash butt welding of railway rails

Abstract: A method and apparatus are provided for flash butt weld joining adjacent rail ends on site during initial field installation where at least one of the rails is fastened to the roadbed, and inclosure butt welding rails as in de-stressing long sections of rail track where both rails are fastened to the roadbed. The method and apparatus apply electrical power to the adjacent rail ends while simultaneously effecting relative closing movement between the rails ends through actuating means so as to bring the rail ends into position to effect current flow between the rail ends, and determining a force necessary to move the adjacent ends into a welding position under varying environmental conditions of the rails as the adjacent rail ends close and during flashing of the adjacent rail ends due to the current flow. The determined force is added to a predetermined upset force dependent on the rail cross-section so as to establish a total forging force that forges the adjacent rail ends into a flash butt weld joint using the total forging force.

Leak detector for lining tank

Abstract: PROBLEM TO BE SOLVED: To identify a leaky point while facilitating formation of a leak detection groove by making the leak detection groove in a sealing plate or a lining material itself. SOLUTION: A sealing plate 22 having a leak detection groove 21 is set to envelop the welding line 41 of lining plates 4 while ensuring watertightness of a lining tank by means of a seal welding 23 and a hermetically sealed leak detection groove 21 is formed. Since the leak detection groove 21 is made in the sealing plate 22 itself, a butt welding single joint using a backing metal can be employed at the weld line 41 between the lining plates 4 or the weld line between the lining plate 4 and a buried metal. Consequently, the quality of welded part is enhanced while shortening the time required for performing the welding and enhancing the quality of welded part.

Butt-welding process using an automatically controlled electro-welding machine

Abstract: It concerns butt-welding of parts made of plastics material(s). For this purpose, the invention proposes correcting, according to an ambient temperature which is measured in the environment of the parts at the moment of welding, at least one of the following parameters: pressure(s) for contact and/or welding of the parts, electrical energy to be supplied to means for displacement of the said parts, stroke(s) of relative displacement of the parts, time for obtaining beads at the end of the parts during the phase of heating the latter.

Resistance welding gun with on-board memory

Abstract: A resistance welding device having a welding current source, a control and/or regulating device for regulating the welding current, and at least one set of interchangeable welding guns on which welding electrodes are mounted in such fashion that they can be pressed toward one another to hold sheets to be welded between them. The interchangeable welding guns contain a local data storage memory located on the welding guns for storing data specific to the operation of the welding guns, and a data interface which can interact with a second data interface located on the control and/or regulating device. When the set of welding guns in attached to the welding device, the two data interfaces are connected thereby permitting the specific operating data for the welding guns to be transmitted to the program memory of control and/or regulating device. The invention also includes self-programming welding guns capable of automatically programming a control and/or regulating device with the operating parameters necessary to optimally operate the set of welding guns.

Weld Formation in Microgravity

Abstract: In order to investigate the effect of gravity on the formation of a weld, gas tungsten arc (GTA) welding was performed both in a microgravity environment and in a terrestrial environment. The microgravity environment was produced for 10 sec with less than 10-5 G by a drop-shaft type microgravity system at Japan Microgravity Center (JAMIC). The material used was an aluminum alloy. It has become clear that in the microgravity environment, the weld bead is formed flatly and a large amount of metal can be welded at once and in any welding position though the weld shape is significantly affected by gravity in the terrestrial environment. When helium rather than argon is used as a shielding gas, the butt weld is formed more flatly because the arc pressure is reduced. Judging from the distribution of the grain structures in the weld, in the microgravity environment, the temperature gradient is smaller than that in the terrestrial environment, and the degree of the constitutional supercooling is higher due to the absence of the heat transfer by gravity.

Structure of welded part of column with beam

Abstract: PROBLEM TO BE SOLVED: To reinforce a butt welded part of a beam flange with a simple constitution in a welded structure of a steel frame column with a steel frame beam, and to surely prevent the breakage of the beam flange against the bend. SOLUTION: An end part of a flange 2a of a steel frame beam 2 of a H- shape steel or an I shape steel 2 is butt-welded to a side plate 1a of a steel frame column 1 such as a steel tubular column using a backing strip. The backing strip is also used for a cover plate 11 which is extended long from one steel frame column side to its counter steel frame column side, the cover plate 11 is attached to the beam flange 2a and fixed thereto through fillet welding 14, 15, a beveling 13 is provided on the end part of the cover plate 11 on the steel frame column side, and the cover plate 11 is fixed to the side plate 1a of the steel frame column 1 by the butt welding 8 of the beam flange 2a.

Residual stress measurement in ferritic steel tube welds using X-ray diffraction

Abstract: The X-ray diffraction (XRD) technique has been used to measure the residual stresses before and after post-weld heat treatment in autogenous butt weld joints in 2·25Cr–1 Mo steel tubes. The tubes are used in the steam generator assemblies of fast breeder reactors. Measurement data show that the stress in the weld centre is ∼150 MPa maximum. The stress distribution around the weld centre is asymmetrical with larger amounts of compressive stress on the side of the tube sheet block. The stress becomes compressive beyond ∼5 mm from the weld centre reaching values of ∼200 MPa and more. Post-weld heat treatment (PWHT) at 923 K for 30 min removes most of the residual stresses and PWHT at 988 K for 2·5 h removes all the residual stresses in the weld regions.

International Conference on Integrity of High-Temperature Welds

Abstract: Opening key notes: a plant user's perspective on the integrity of high temperature welds, D.J. Allen. Ferritic welds: in-service cracking mechanism affecting 2CrMo welds in 1/2CrMoV steam pipework systems, S.J. Brett performance of repair welds on aged Cr-Mo piping girth welds, R. Viswanathan, D.W. Gandy development of a normalizing heat treatment to restore "as-new" properties in service-aged CrMoV steel, D.J. Allen et al the repair welding of power plant without post-weld heat treatment, S.J. Brett et al evaluation of long-term creep rupture strength of weld joints of low-alloy CrMo steel boiler tubes, J.T. Hakl et al recent developments in welding consumables for P(T)91 creep-resisting steels, Z. Zhang et al the creep-rupture properties of thick-section electron beam welds in 1/2CrMoV, 2CrMo, modified 9CrMo((P91) and 12CrMoV(X20) steels, K.E. Jones temperhead welding of P-Nos 4 and 5 materials, D.W. Gandy et al review of type IV cracking in piping welds, F.V. Ellis, R. Viswanathan the breakdown of welded joints in service as a result of reduced structural stability, A.R. Foret et al the creep and fracture behaviour of thick-section, multi-pass weldments, J.D. Parker. Creep crack growth: creep crack growth properties for the defect assessment of weldments, S.R. Holdsworth. Austenitic and nickel base welds: reheat cracking and strategies to assure integrity of type 316 welded components, M.C. Coleman et al direct measurement of residual stresses at a repair weld in an austenitic steel tube, L. Edwards et al high-temperature mechanical properties in laser welds of co-based superalloy and its improvement by laser surface melting, Y. Makino et al the fatigue and creep-fatigue behaviour of type 316L(N) structural weldments of 550 C grades, I. Bretherton, S.K. Bate creep-fatigue evaluation procedure of stainless steel welded joints for the design of fast breeder reactors, T. Asayama creep-fatigue life estimation for austenitic stainless steel weldments, Y. Takahashi et al fatigue and creep fatigue of 316(N) high-temperature welded plates submitted to reverse bending, L. Le Ber et al investigation and repair of a leak at a high temperature stainless butt weld, J.W. Dunn et al. Dissimilar welds: the high-temperature performance of austenitic-ferritic dissimilar welds, J.A. Williams assessment of creep and creep-crack growth of 21/4CrlMo/Inconel 182/type 316 dissimilar metal weld features in pure bending, I. Curbishley, D.G. Hooton. Design codes, standards, and analytical methods: analytical and computational stress analysis of welded components under creep conditions, T.H. Hyde et al. (Part contents).

Method and device for welding annular article of large diameter

Abstract: PROBLEM TO BE SOLVED: To efficiently perform the butt welding of tubes of large diameter to each other with small number of workers. SOLUTION: In welding each butted part 7 of a plurality of iron tubes 1a-1d, the iron tubes are turnably supported by a turning equipment 2, a submerged arc welding equipment 11 is installed corresponding to each butted part 7, and a back chipping equipment 32 is installed corresponding to each butted part. In addition, video camera devices 22, 23, 36 to photograph each welding part and back chipping part are installed, and the welding equipment 11 and the back chipping equipment 32 are individually or collectively operated from the side of a control panel 51 provided with monitors 53, 54 of the video camera devices 22, 23, 36.

A study of the structure of dissimilar submerged arc welds

Abstract: Butt welds have been produced using the submerged arc welding (SAW) process to join a carbon steel plate of normal shipbuilding grade to an austenitic stainless steel 316LN plate. Variables used in this work were the position of the consumable wire in the weld preparation and the ferrite number of the consumable wire. Abnormally high hardnesses were measured in some regions of the welds. These were related to the central position of the consumable wire in the weld preparation. Undesirably low ferrite numbers were related to the ferrite number of the consumable wire and also to the central position of the consumable wire in the weld preparation. The position of the consumable wire in the weld preparation controlled the relative dilution from the parent plates, and when the dilution from the 316LN steel was increased by off-setting the wire to that side of the weld preparation, the high hardness regions were no longer found. Similar optical microstructures were found to have significantly different hardnesses, which were related to the dilution effects, which were also related to the wire position within the weld preparation. Martensite was observed by transmission electron microscopy (TEM) in some of the regions of high hardness, and in other areas, the presence of extensive precipitation of M23C6 was seen. The presence of M23C6 was due to the effects of high heat input or reheating of areas by subsequent passes. The determination of the ferrite number in dissimilar welds was problematic. Fertiscope determinations appeared to be influenced by magnetic effects from adjacent areas of the carbon steel. Image analysis was found to be less reliable than the Feritscope for the determination of the ferrite numbers in dissimilar welds.

Automatic tracking process of the joint bevel for the butt welding of pipes and equipment for the embodiment of the process

Abstract: A process for automatically tracking a joint bevel during butt welding of coaxial pipes includes the steps of observing electrical parameter values relating to the voltage, current and voltaic arc impedance and comparing these values with preset sample values stored in a governing unit. The governing unit controls a driving source for the orientation of the welding torch in the joint bevel.

Automatic welding device for piping and welding method for piping

Abstract: PROBLEM TO BE SOLVED: To improve the quality of butt welding for the piping, and to facilitate a welding operation. SOLUTION: In an automatic welding guide ring 19 for the piping, mounted on a groove butting part 18, a centering adjustment mechanism 26 for pushing out the piping 10, 12 and centering the piping each other is revolvably arranged. After centering the piping each other by the centering adjustment mechanism 26, by moving a welding head 42 rotatable along the inside wall of the automatic welding guide ring 19 for the piping, the groove butting part 18 is welded. Hereupon, first slider and second slider are provided between traveling ring 40 and welding torch, and since a copy roller copying the groove butting part is provided on the welding torch side, even when the revolving locus of the welding head 42 is not parallel to the groove butting part 18, the welding torch is revolvably moved on the groove butting part. Therefore, the welding is enabled with a high quality and the welding operation is facilitated.

Welding method in stainless piping and welding auxiliary tool used in the welding method

Abstract: PROBLEM TO BE SOLVED: To provide a welding method in a stainless piping capable of preventing a weld burn and fume adhesion and obtaining suitable back-bead. SOLUTION: In the case of mutually butt welding stainless pipings 2 by back-bead welding, a shield gas feeding box 4 is arranged in the inner surface side of a butt weld zone 3, the shield gas is directly made to blow out of the blow opening 4a of the shield gas to the butt weld zone 3, and moreover the pressure in the inside space part 10 within the piping 2 including the weld zone 3 is regulated with a pressure regulating piping 8 opened into a water tank 7.

Production module for assembly welding and finish welding of sheet metal components comprises a single welding station and two pallets with clamping devices suited for these two types of welding

Abstract: The production module includes a single welding station (1) and two pallets (5, 3) provided, respectively, with clamping devices (6) for assembly welding and clamping devices (4) for finish welding. It also includes unit for lifting the assembly welded sheet metal component (8) from the pallet (5) and transferring it to the pallet (3) for finish welding. An Independent claim is given for operating such a production module. It covers specifically component transfer from the pallet (5) to the pallet (3).

Welded joint structural material

Abstract: PROBLEM TO BE SOLVED: To obtain satisfactorily high joint strength even through the bending of a base stock, an ununiform cut end surface or defective joint part position setting or the like and the fluctuation of a welding condition owing to these are caused by forming the thickness of a joining part of a pair of members which are composed into a joint structural material by being welded thicker than that of a part succeeding thereto SOLUTION: Thick wall parts 3, 4 which are thicker than parts succeeding to butting end parts are respectively formed into the butting end parts of members 1, 2 The thick wall parts 3, 4 are parts to be joined by welding, and the parts succeeding to the thick wall parts 3, 4 are provided with a thickness required as ordinary members 1, 2 In such a manner, since joining end parts of the members 1, 2 are provided with a thick shape, even though positions of the butting end parts of the members 1, 2 are vertically deviated in the case of butt welding those, a weld metal which is satisfactorily thicker than a thickness of a base metal part (stationary part) is formed between both, and satisfactorily high joint strength is obtained

Manufacture of steel pipe pile coated with titanium clad steel

Abstract: PROBLEM TO BE SOLVED: To provide a method for manufacturing a steel pipe pile coated with titanium clad steel excellent in workability and working efficiency and easy in securing a welding quality. SOLUTION: A groove is provided at a butting part of a titanium clad steel plate 2, titanium fitting members 2a at the end in the up and down directions are removed, titanium clad steel plates 2 are bent in a semi-cylindrical shape and made into a cylindrical shape by butting them on a base material 3 of a steel pipe pile, steel base materials 2b of the butting parts are welded to each other and the steel base material 2b and the base material 3 of the steel pipe pile are welded as well, a clearance on a butt welding part 6 and a clearance generated from a difference in levels between the surface of the titanium clad steel plate 2 and the surface of the base material 3 of the steel pipe pile are covered with a strip shape titanium cover plate 8, the titanium cover plate 8 and the titanium clad materials 2a are welded (9) and by welding (10) the periphery of bending parts 8a of the titanium cover plate 8 with an Ag filler material, these clearances are sealed. COPYRIGHT: (C)1999,JPO