Showing papers on "Butt welding published in 1991"

Apparatus and method for automatically aligning a welding device for butt welding workpieces

Abstract: Apparatus and method for aligning a welding device along the center of a gap defined by confronting edges of at least two workpieces to be joined, wherein relative motion between the welding device and the workpiece gap occurs along a longitudinal axis substantially parallel to the gap such that the proximal edges of the workpieces can be joined by forming a weld seam along the gap during the relative motion. The apparatus preferably includes an imaging system for determining the location of the gap center relative to a predetermined two dimensional coordinate system by monitoring an image of a vision area along the gap downstream of the welding zone. In a preferred embodiment, the imaging system is effectively isolated from the welding zone through use of a high magnification optics system, a shroud structure, an independent light source, and a vectored jet of inert gas supplied to the welding zone.

Flat sided forming tube for a form-fill-seal machine

Abstract: A form-fill-seal machine, for converting a continuous sheet of sealable film into bags, filling and then sealing the bags, in which the vertical forming tube is fabricated from a rectangular sheet of stainless steel material by making a plurality of equal angle and equal spaced bends in the stainless steel material and joining the ends together with a butt weld such that the vertical forming tube has a regular polygon cross section

Low thermal inertia heater

Abstract: A mold, having a mold cavity commensurate with the shaping, forming or welding to be made, includes an RF energized heater in close proximity to the mold cavity for heating plastic tubing placed within the mold cavity to a temperature sufficient to shape, form or weld the plastic tubing. An RF generator, electrically connected to the RF energized heater, monitors the power applied as a function of the temperature of the heater to heat the plastic tubing to a precise temperature. The mold is of thin wall construction with minimal thermal inertia to expedite both heating and cooling. Various configurations of the mold may be made to form tip shaping, forming or welding, butt welds, annular welds and the like to weld single thermoformable elements or join multiple thermoformable elements.

Laser butt-welding device and method

Abstract: A device and method for butt-welding metal strips using a laser is disclosed. The present invention utilizes clamping bridges to selectively grip the metal strips to be welded together. The ends of the metal strips are first prepared for welding by severing the ends using a movable laser. After the prepared strip ends are moved into butt-welding relationship, the same laser is used to weld the two strips together. Where the strips are of differing width, the laser may be rotated and its height above the strips adjusted in order to achieve the proper welding angle. Where one strip is continuously moving, a buffer facility is provided for selectively storing a portion of the continuously moving strip prior to cutting and welding. Through adjustment of the buffer facility, the clamped portion of the continuously moving strip, i.e. the trailing portion, remains stationary during cutting and welding while the leading portion of the strip continues to advance. Such a buffer facility might be used where the strip is undergoing a continuous process, such as the application of coating, downstream from the welding.

Apparatus for butt-welding of plastic parts

Abstract: A heating device (7) which can be swung between two clamping devices (4), (5) has a heating element (12), by means of which the parts (1, 2) to be welded are contactlessly heated by heat radiation. The heating element (12) has a metal plate (13) which is covered with ceramic and is electrically heated by means of heating cartridges (15).

Aluminothermic welding device crucible and crucible cover for use therewith

Abstract: An aluminothermic welding device. The device, which is for the butt welding of two metal members such as railroad rails, comprises a mould and a crucible the respective upper and lower faces of which are so formed with mutually complementary respective depressions and/or reliefs as to enable the crucible to be placed on the mould in a position in which the discharge aperture of the crucible and the pouring bush of the mould are coaxial and turned downwards and upwards respectively. This ensures the correct positioning of the crucible in relation to the mould. The crucible can also be constructed in a form enabling it to be used once and from a material selected for this purpose and advantageously differing from the material used for the mould.

Full-Scale Tests of Butt-Welded Splices in Heavy-Rolled Steel Sections Subjected to Primary Tensile Stresses

Abstract: Experimental results from full-scale testing of full and partial penetration butt-welded splices of ASTM A6 Group 4 and 5 heavy-rolled sections are presented. Welded splices of the test specimens were subjected to primary tensile stresses as induced by pure bending. The partial penetration splice failed in a brittle manner with no apparent ductility. However, it was able to develop and exceed its nominal capacity. Qualitative explanations are given as to the cause of the observed failure. The splice with full penetration welds exhibited satisfactory strength and ductility. It is believed that a great amount of care must be taken in the execution of this weld type. Future research needs are examined.

Fabrication of oxide dispersion strengthened ferritic clad fuel pins

Abstract: A resistance butt welding procedure was developed and qualified for joining ferritic fuel pin cladding to end caps. The cladding are INCO MA957 and PNC ODS lots 63DSA and 1DK1, ferritic stainless steels strengthened by oxide dispersion, while the end caps are HT9 a martensitic stainless steel. With adequate parameter control the weld is formed without a residual melt phase and its strength approaches that of the cladding. This welding process required a new design for fuel pin end cap and weld joint. Summaries of the development, characterization, and fabrication processes are given for these fuel pins. 13 refs., 6 figs., 1 tab.

Laser beam welding method for rust preventive steel sheets

Abstract: PURPOSE:To enhance the welding quality of rust preventive steel sheets subjected to rust preventive treatment such as galvanization on the surface. CONSTITUTION:This is the laser beam welding method of the rust preventive steel sheets where an end of one rust preventive steel sheet 1 is abutted on an end of the other rust preventive steel sheet 2, the butt part is irradiated with a laser beam L while a filler wire 3 is fed to a gap generated on this butt part and shielding gas is supplied to a molten part of the butt part to perform butt welding and the shielding gas G2 is supplied from the same direction as the feed direction of the filler wire 3.

Spot resistance welding method and welding electrode for implementing the method

Abstract: The subject of the present invention is a method of spot resistance welding at least two metal pieces (1, 2). The method consists in pressing the pieces (1, 2) between two electrodes (3, 4), in determining the overall resistance between the electrodes (3, 4), and the contact resistances of each electrode (3, 4) with the piece (1, 2) with which it is in contact, in calculating the contact resistance between the said pieces by the difference between the overall resistance and the sum of the resistances of each piece and of the piece-electrode contact resistances, in determining the actual intensity of the electric welding current, and in adjusting the various welding parameters for the said pieces (1, 2) in order to maintain a constant optimal intensity of the electric welding current. The subject of the present invention is also a welding electrode for implementing the method.

Gas shielding tools for welding

Abstract: PURPOSE: To easily and surely carry out rear gas shielding in butt welding of pipes in a short time, to manage to use a. small quantity of expensive argon gas and to save time. CONSTITUTION: The gas shielding tools for welding capable of being inserted into the pipes 4 to be butt-welded are constituted of a cylindrical gas blowoff pipe 1 where many small holes 6 for blowing off gas are provided on a peripheral annular wall, a gas introduction pipe 2 provided successively on one end thereof and plural leaf springs 3 whose one end is fixed on both ends in the directions before and behind the gas blowoff pipe 1 with the other end free. When gas shielding of the weld zone rear is carried out by using these gas shielding tools for welding, the tools are first inserted into the pipes so that the gas blowoff pipe 1 is located at the weld zone 5 rear side in the pipes 4 to be butt-welded. In this state, the gas blowoff pipe 1 is set at the center of the pipes 4 by the spring repulsive force of the leaf spring 3 and a gap between the inside of the pipes 4 and the gas blowoff pipe 1 is maintained constant. Gas shielding of the weld zone 5 inside is effectively carried out by the argon gas A blowoff from the small holes 6. COPYRIGHT: (C)1993,JPO&Japio

Method and device for welding pipes and a pipe-layer

Abstract: In a method for welding together pipe ends of pipes held mutually in line the welding process is automatically controlled subject to the angular distance traversed by the welding lance.

Butt laser beam welding method

Abstract: PURPOSE:To set a butt gap with high accuracy by inserting shims having thickness corresponding to the butt gap quantity into the shear-cut surfaces of materials to be welded. CONSTITUTION:In butt laser beam welding where a couple of metallic sheets 1 and 2 to be welded are subjected to butt welding with the specified gap quantity S, the metallic sheets 1 and 2 to be welded are shear-cut, then, the shims 5 having thickness corresponding to the gap quantity S are inserted into the shear-cut surfaces of both sheets in the vicinity of both ends thereof, both metallic sheets are abutted on each other via the shims 5 and then, subjected to laser beam welding. After welding, the remaining sheet ends of the shims are then cut and removed. Consequently, the butt gap quantity can be obtained with high accuracy.

Alloy 625 Weld Overlays for Offshore and Onshore Projects

Abstract: This technical report presents the most complete and in-depth design, research and fabrication of Alloy 625 weld overlayed carbon steel pipe and fittings such as: 90 degree and 45 degree LR Elbows, Tees, Dished Heads, Reducers, Weld Neck Flanges, Valves, Spools, Manifolds, Nozzles, Blinds and so forth. Major developments for Offshore Projects took place in Calgary, Canada during 1989, 1990 and continued through 1991 such as: Development of an entire range of Alloy 625 weld overlay and butt welding procedures to cover majority of the welding processes: SAW, Pulsed GMAW, SMAW, GTAW, FCAW and base materials such as: Pl and 4130 with thicknesses from .250 in. (6.3mm) to no limit to be weld overlayed or butt welded. Development of a wide range of welding procedures to join dissimilar and similar materials such as: Pl to Pl, P43 to P43, Pl to P45, P43 to P45, 4130 to 4130, 4130 to P43 etc. All using the same filler metal: Alloy 625. Development of special welding consumables with special formulation to be used on Offshore Projects. Development of a unique welding technology and welding technique to provide a low iron content Alloy 625 weld deposit on carbon steel base mater ial. .Development of a specialized welding equipment to perform weld overlay on 45 degree and 90 degree LR Elbows with any exotic welding filler metal includinq Alloy 625, employi.nq a high productivity SAW System with near zero defect rate. ^. Corrosion tests performed on Alloy 625 weld overlay deposits and corrosion tests performed on self contained Alloy 625 weld overlayed Autoclaves. Complete study of Alloy 625 flux cored wire: weldability, corrosion testing and weld defect occurrence while weld deposits are performed using FCAW fillers available today. Superalloys 718,625 and Various Derivatives Edited by Edward A. Imia The Minerals, Metals & Materials Society, 1991

Hand arc welding of rail line butts - butting ends are cut with vertical ends facing each other and are preheated

Abstract: To butt the ends of railway rails, through hand arc welding, the butting ends (1, 2) are cut with vertical ends facing each other and are preheated During welding, their bottom ends (6, 7) with a gap (3), are on an underlay (8) of ceramic, glass-type or metal material The rail ends are cut eg by a cutting disc The underlay (8) is a plate of normal glass, ceramic or copper The bottom sections (6, 7) are welded with an uninterrupted beading (14) over the profile up to the rail webs (11, 12) The underlay plate (8) is removed and any projecting welding at the edges (15) of the rail feet are cut away with a disc so that the welding bead projects 1-2 mm above the profile of the rail feet After finishing the welded seam at the edges (15), the rail profile is hammered The webs (11, 12) are welded using copper pads on both sides with the inner wall against the web near the welded seam and the under side of the rail head to give a gap of about 3 mm After welding the rail heads, the welded seam at the head and the side surfaces is worked into a profile mass while the under side of the rail head is held at an over mass of about 3 mm The welding at the head surface is done with a hard surface electrode, and micro alloying components are in the electrode for the butt welding The electrode has a double mantle, where the outer mantle is non-conductive, of such a length that a single electrode can be used for the whole of the rail foot (6, 7) The composition of the electrode shrouding is a thin fluid of slag passing from the welding point or the silicates content from the underlay ADVANTAGE - The operation gives simple welding process with minimum preparation time

Small sized motor

Abstract: PURPOSE:To obtain a miniaturized rotating electric machine with high quality at a low cost by fixing a stator core and a bracket by laser welding. CONSTITUTION:The peripheral surface of a stator core 1 is welded together with an end plate 3 as a unit. The end plate 3 has a faucet section 3a, a bracket 11 and a cover 12 are fitted to the faucet section 3a to form together a unit by laser welding. When the stator core 1 is a single body, a stator coil 2 is inserted thereinto, and the end plate 3 and bracket 11 is welded by laser in the same state. Laser welding has low heat capacity, so that butt welding is effective, and even if the overall circumference is welded, thermal strain is so small that deep welding can be made. Accordingly, laser was irradiated to butt surface of the bracket 11 and end plate 3 from the peripheral surface side, so that welding can be made so deeply. According to the constitution, rigidity is increased, and vibration is controlled. Accordingly, a miniaturized rotating electric machine having high rigidity and low noises at a low cost can be obtained.

Continuous welding tube making method

Abstract: PURPOSE:To attain the complete elimination of a plating metal by spraying an injection flow of a liquid containing abrasive grains to the surface of each edge part before executing cylindrical forming of a plating steel plate. CONSTITUTION:A band-like plating steel plate S is transferred continuously, and the plating steel plate S is formed to a cylindrical shape. By bringing an edge part of the formed plating steel plate to butt welding, continuous welding tube making is executed. In this state, before forming the plating steel plate S to a cylindrical shape, a nozzle 11 is directed to the surface of each edge part of its right and left. Subsequently, an injection flow of a liquid containing abrasive grains is sprayed to the edge part of the plating steel plate S from the nozzle 11. Next, a metal elimination processing for grinding and eliminating the plating metal on the surface of the edge part is executed. In such a way, a sound tube quality can be guaranteed.

Butt welding of thin stainless steel sheets with the “rippled mode“ Nd-YAG laser

Abstract: The “wide bead formation” method has been developed for butt-welding of thin steel sheets whose thickness are less than 300μm. This method eases the precise butting requirement in the practical production lines. The “rippled mode” Nd-YAG laser has been also developed in order to further improve the welding characteristic of thin steel sheets compared with that using CW YAG laser. By applying this laser for the wide bead formation method, less than 150μm thick steel sheets could be butt-welded without any defects.The “wide bead formation” method has been developed for butt-welding of thin steel sheets whose thickness are less than 300μm. This method eases the precise butting requirement in the practical production lines. The “rippled mode” Nd-YAG laser has been also developed in order to further improve the welding characteristic of thin steel sheets compared with that using CW YAG laser. By applying this laser for the wide bead formation method, less than 150μm thick steel sheets could be butt-welded without any defects.

Welding method for aluminum alloys

Abstract: PURPOSE:To prevent weld defects by subjecting the pure Al side position to non-filler material root running and then, performing filler material welding thereon by a next pass. CONSTITUTION:Pure Al alloy material (A1000 group) 1 and Al-Mg alloy material (A5000 group) 2 having different heat conductivity and thickness capable of one-pase welding are subjected to butt welding with a TIG torch 4 or plasma as a heat source. The target position of a welding arc is then made to the position coming by (l) which is about thickness (t) up to the pure Al alloy 1 side from the groove center 7. A root part 3 is molten sufficiently and a stable back bead having the even back bead width of both base metals 1 and 2 is formed by subjecting this position to non-filler material root running. Afterward, filler material welding is performed by the next pass. Consequently, a blowhole, incomplete fusion, etc., can be prevented by maintaining the specified throat depth.

The Effect of Weld Metal Strength Mismatch on the Deformation and Fracture Behavior of Steel Butt Weldments

Abstract: : Considerable Naval and industrial experience has indicated the engineering utility of using weld metal having strength greater than the plates being joined (over-matching). Overmatching shields the weld region, which typically has lower toughness than the plate and is often the site of defects, from the high strains that develop during an overload. This practical advantage, coupled with the ease of achieving overmatch in lower strength steel alloys (80 ksi yield strength or less) has led to codification of overmatching as a requirement in most structural design codes and fabrication specifications. However, overmatching has certain economic and technical disadvantages which undermatched (weld metal strength less than plate strength) systems might alleviate. This report reviews investigations concerning the deformation and fracture characteristics of simple mechanical test specimens containing butt welds, focusing on how the relative strength of the weld deposit and the plate influences these characteristics. All analytical and experimental evidence available indicates that plastic strain concentrates into the zone of the lowest material strength in a transversely loaded weldment. Thus, plastic strains in undermatched weldments concentrate in the weld deposit while in overmatched weldments they concentrate in the plate.

Estimates of regions of stress concentrations in T butt weld geometries

Abstract: Values of the surface and the die away distance to unity of stress concentration factor have been found on typical geometries of «T» butt and cruciform joints using finite elements

Butt welding method in welding machine and welding head used for its method

Abstract: PURPOSE:To eliminate the welding failure caused by the variance of a butting part and to execute the welding extending over a wide range by irradiating a laser beam and evaporating the binder of a filler material, while injecting vapor deposition preventive gas, melting the filler material and welding the butting part. CONSTITUTION:A filler material FM is supplied to the butting part WT of a work W from a first nozzle 3, and thereafter, by irradiating this filter material FM with a laser beam from a first optical fiber 5, a binder is evaporated from the filler material FM. Subsequently, by melting the filler material FM by a welding means, the butting part WT of the work W is welded. By evaporating the binder from the filler material FM at the time of welding working, and injecting vapor deposition preventive gas, while welding is being executed, the evaporating material of the binder or a molten metal does not stick to the butting part WT of the work W, therefore, satisfactory welding working is executed. In such a manner, the quality of a butting welding part is secured, and also, a welding failure caused by the variance of the butting part WT is eliminated, and since the correcting process is not required, the productivity is improved.

Efficient Welding Fabrication of Extruded Aluminum Mat Panels

Abstract: : The program had the following main objectives: to design and procure welded extruded access/egress (A/E) mat panels, to determine feasibility of and to provide means for fabrication of Ribbon Bridge (RB) and Light Assault Bridge (LAB) deck panels using the technology developed under this program, to develop advanced equipment and technology for assembling and welding of A/E mat panels, and to study mechanical and metallurgical properties of welded joints. The existing practice is to design and build roadway mat panels (or bridge deck panels) from wide, single-piece extruded 6061-T6 aluminum components. In order to avoid difficulties associated with procurement of large circle-size extrusions, which are expensive and not readily available, the panel cross- section was constructed from smaller extruded elements using welding. In this respect, various aspects of weldment design were studied, including design of welded joints, and fatigue analysis of their performance since the panels will be subjected to severe environment and heavy load conditions. Also, a procurement base for extruded panels was explored through analysis of data obtained as a result of an industry survey. A state-of-the-art experimental automation fabrication system was developed for assembling and welding of long extruded components. It allows two longitudinal butt welds between three subpanels to be performed simultaneously on each side of the subpanels to form a full-size mat panel up to 28 in. (711 mm.) wide-,and up to 13 ft. (6,934 mm.) long, with a possible extension up to 28 ft. (8,534 mm.) for fabrication of bridge deck panels. A unique fixture was developed as an integral part of the system to meet the requirements of a welding procedure developed to offset complicated metallurgical reactions typical for welding of age-hardenable aluminum alloys.

Butt welded sheet and butt welding method for high damping steel sheets

Abstract: PURPOSE: To perform butt welding on two high damping steel. sheets without causing peeling. CONSTITUTION: The two high damping steel P opposed to each other by providing a gap δ corresponding to the quantity of penetration of a wire 7 are first spot-welded at several places and tack-welded together. Then, after these high damping steel sheets P are clamped firmly, while inert gas is supplied to the rear rear of a joining part and the inside of the gap δ an electric current to the extent of 1/10 of usual welding is sent to a torch 6 and these joining edges are molten along with the wire 7 and butt-welded together while resin gas generated in the high damping steel sheets P is released. COPYRIGHT: (C)1993,JPO&Japio

Method for welding fine wire by laser

Abstract: PURPOSE:To easily allow the butt welding of fine wires by butting a pair of the fine wires, holding the butt parts by means of a holder, the part in the butt position of which consists of a material to allow the transmission of a laser beam, and irradiating the butt parts with the laser beam. CONSTITUTION:A pair of the fine wires 1a, 1b to be welded are held in the holder made of the transparent material, such as glass, which allows the transmission of the laser beam, by butting the end faces in a through-hole 3 provided as a cavity part for insertion. The butt parts 8 are irradiated with the laser beam 4 from the outside and are thereby welded. The fine wire is pulled from the holder 2 after the welding or the holder 2 is broken and the fine wire is taken out. The inside surface shape of the through-hole 3 of the holder 2 is made to comply with the outside surface shape of the fine wire 1 and is formed by adding the allowance permitted after the welding thereto. The build-up and burn-through of the weld zone are prevented in this way and the operation to register the tine wires is simplified. The butt welding of the fine wires is thus easily executed.

Automatic butt welding machine

Abstract: PURPOSE:To automatically and exactly decide the welding quality by comparing the melting quantity at the time of finishing welding detected by a melting quantity detector with the preset reference melting quantity to decide the propriety of the melting quantity at the time of finishing welding. CONSTITUTION:The melting quantity detector 12 detects a traveling stroke of a melting quantity detection arm fixed on a movable electrode 6 at the time of welding and detects the melting quantity from both end faces 7a and 8a in opposition of a couple of members 7 and 8 to be welded. A welding quality deciding device 15 compares the melting quantity at the time of finishing welding detected by the welding quantity detector 12 with an upper limit value and a lower limit value of the preset proper melting reference quantity and decides the propriety of the melting quantity at the time of finishing welding. By this method, the welding quality on a welded product can be decided automatically and a accurately.

Manufacture for sink dewatering cage

Abstract: PURPOSE:To reduce the production cost of the sink dewatering cage with high safety by making perforated plate to a cylindrical body, drawing the upper and lower peripheries thereof, forming the flange part and the bottom part and welding the prescribed shape formed plate. CONSTITUTION:Whole of the surface of the stainless plate 1 is perforated with dewatering holes 2, 2 expect spaces S1, S2, S3, S4 at 4-side peripheries. This is rolled into the cylindrical body, the end peripheries 1b, 1d are subjected to butt welding, the outer flange 4 is subjected to pressing at the upper end periphery and the inner flange 5 is subjected to pressing at the lower end periphery. Next, the circular perforated plate 7 which is agree with the circular hole 6 formed with the lower flange 5 is inserted and both ends are butt welded, on the other side, the arrow shaped chord 8 is mounted at the upper end part. Therefore the reduction of producing cost for the dewatering cage with safety are realized.