Showing papers on "Welding published in 1970"

Laser welding of prostheses--an initial report.

Abstract: Experience in laser welding fixed and precision removable partial prostheses has shown that, economically speaking, a considerable amount of time is saved when laser welding is used. The accuracy of the assembled restoration reflects the accuracy of the initial impression, since all welding is done on the master cast. Inaccuracies in assembly caused by transfers from the master cast along with investment and heat distortions are avoided. Anatomic form of the interproximal region is not obliterated. Maximum esthetics in the anterior section of the mouth is afforded, because individual sculpturing and veneering of abutments and replacements can be accomplished without the restrictions enforced by solder-joint design.

Air cooled welding gun

Abstract: The disclosure is directed to a welding gun for MIG welding in which the gas cup and contact tip of the nozzle are secured in place by a single clamp type device that permits ready replacement of both. The nozzle in turn is connected to the gun handle by a single clamp device that permits ready replacement of the nozzle as a unit or ready change of positioning of same relative to the handle. The nozzle is arranged to provide for cooling of the gas cup through air fins on the nozzle that are in electrically insulating good heat transfer relation to the gas cup. The nozzle is in the form of an elongate extruded body having its end portions threaded for threaded attachment thereto at its handle end of a finger forming fitting to which the clamp that holds the nozzle to the gun handle is applied, and for attachment to its discharge end a finger forming fitting to which is applied the clamp that holds the gas cup and contact tip in place. Interposed between the gas cup and the body discharge end fingers is a contractable sleeve formed from a material having good heat conducting characteristics that is covered with a coating of a material that is electrically insulating but of good heat conducting characteristics.

Resistance welding of sheet metal coated with layers

Abstract: The invention relates to a method for the resistance welding of sheet metal coated with layers, wherein firstly electrical contact is established between the sheets to be interwelded and between the welding electrodes and said sheets, and subsequently welding is effected across the coating layers The invention relates also to machines for carrying out this method

Semiautomatic welding apparatus

Abstract: This invention is a welding apparatus operable to automatically provide an electrode surrounded by a shielding gas for welding through an arc-welding process. More particularly, this invention is a welding apparatus having a welding gun assembly connected through a cable assembly to a quick connector assembly which, in turn, is adapted to be inserted within a supply adapter assembly to transfer gas, welding wire, and electrical power to the welding gun assembly. Additionally, this invention relates to a welding apparatus operable to supply welding wire while having structural features (1) allowing for the ready disconnecting and connecting to a supply source, and (2) to maintain the gun assembly in a cool condition during welding operations; and (3) achieving lightweight features for ease of usage.

Wall frame structures

Abstract: A wall frame structure made up of upper and lower sheet steel plates between which extend a number of studs, the studs being connected to the plates, preferably at both ends by means which engage with co-operating means on the plate in such a manner that the two are secured together without the use of welding, nuts and bolts or rivetting.

Gouger attachment for conventional electrode holder

Abstract: An attachment is provided for a conventional electrical welding electrode holder. The attachment substitutes a nozzle for the conventional electrode tooth member so that compressed air is blown along the electrode to blow away molten metal. The attachment converts a standard electrode holder to a gouging device.

Method of producing crack-free electron beam welds of jet engine components

Abstract: Crack-free welds of jet engine components formed essentially of a heat resistant nickel-base alloy having a tendency to be weldcrack sensitive are produced by abutting selected surface of at least a pair of structural elements of said nickel-base alloy, the elements being assembled in welding relationship with an iron-base shim therebetween, the elements being electron beam welded together into a unitary structure by melting the iron-base shim at the interface of the abutting surfaces, whereby the resulting weld which is an alloy of the iron-base shim and the nickel-base alloy is crack-free.

A device for clamping and moving together thermoplastic pipes for flush-welding

Abstract: A device for heating pipes which are to be flush welded includes two hinged clamps each of which is connected to a supporting piece. One of the supporting pieces is attached to a guide pin with the other supporting piece movably mounted thereon.

Method and device for friction welding

Abstract: The method of friction welding is applicable to surfaces to be welded with any type of marginal boundary. Two workpieces to be welded together are arranged against each other at the surfaces to be welded and are heated to welding temperature by a relative oscillatory movement along such surfaces. The relative oscillatory movement is effected by way of relative rotatory movement with the workpieces remaining substantially parallel to each other. A device for carrying out the method comprises a workpiece holder driven by an eccentric body rotatable about an axis. A circular rotatory path is defined on the body and the eccentricity of this path is adjustable relatively to said axis, the holder being movable at least two-dimensionally in a plane corresponding to the orientation of the surface to be welded. The holder is guided on the path of progression of the eccentric body so that, upon rotation of that body, all parts of the holder perform rotatory movements of equal size and circular shape with a radius equal to the adjusted eccentricity of the eccentric body.

The cohesion of previously fractured Fcc metals in ultrahigh vacuum

Abstract: The cohesion of clean surfaces of the fcc metals Ag, Al, Cu, and Ni was investigated using the technique of cold welding specimens previously fractured in an ultrahigh vacuum The cohesive strength of the weld increased with compressive load, all data falling on a single curve with slight positive curvature when the cohesive strength and compression load were normalized through the initial fracture strength of each metal The cohesion coefficients ranged from 062 to 115 and were in accord with those obtained using more elaborate techniques of surface preparation and testing It is proposed that the essentially constant cohesion coefficient obtained for all the unalloyed fcc metals resides in the fact that the area of contact produced by a given compressive load is inversely proportional to the fracture stress of the metal and the cohesive strength is directly proportional to this fracture stress A lowered cohesion coefficient was observed for copper specimens which had recrystallized in the vicinity of the interface either during the cold welding or as the result of a subsequent heat treatment

Electric arc welding gun having a nozzle with a removable metal liner to protect the nozzle from weld splatter

Abstract: The welding gun construction utilizes a nozzle member having an opening for directing an inert gas against the work to be welded. A tubular welding tip is disposed centrally within such opening to guide a welding wire toward the work. A welding arc is drawn between the work and the wire. A tubular metal liner is received within the opening to protect the nozzle member from weld splatter, which comprises molten metal globules thrown up from the welding area. The solidified weld splatter accumulates within the liner, which can be removed and disposed of as needed, before the weld splatter builds up to a thickness sufficient to cause a short circuit between the welding tip and the nozzle member. A new liner is then inserted into the nozzle. The liner is formed with a retaining element whereby the liner is held within the nozzle against accidental dislodgement. Such retaining element may take the form of an oval portion, one or more spring fingers bent outwardly from the liner, or a dimple portion formed by outward deformation of the liner. A pocket or tapered portion may be formed within the nozzle member to retain the outwardly projecting fingers or dimples. The liner may also be arranged for insertion into the nozzle from the rear, and may be retained in the nozzle by an outwardly projecting flange on the rear portion of the liner.

Dual welding wire feed for arc welder

Abstract: This application discloses an electric arc welding system using two welding wires fed through a single torch, with means for driving either wire in either direction The torch, or torch tip, has a wire passage which, at the extremity of the tip, will pass only one of the two wires The two wires are threaded through the torch side-by-side, and with one in a retracted position, the other can be fed from the torch Thus, assuming two wires of different characteristics, a change over from one to the other can be quickly made

Method for welding vertically extending pipe sections together

Abstract: A method for welding substantially vertically extending pipe sections together in end-to-end relationship, wherein at least one of the adjacent ends of the sections is bevelled to provide a welding space between the sections, and a means for depositing weld metal is moved about the sections to deposit weld metal in such space while all of the welding parameters are controlled and maintained irrespective of environmental-induced movements of the sections.

Machine for maintaining constant the distance of a cutting or welding torch from the work piece

Abstract: In a torch cutting or welding machine an apparatus for maintaining constant the distance of the cutting or welding torch from a work piece being cut or welded in which the sensing electrode is secured to the torch and forms a capacitance with a surface portion of the work piece, resonant and discriminating circuits producing a predetermined voltage corresponding to a predetermined value of the capacitance and such voltage operating a positioning motor which positions the torch to establishing the original capacitance value corresponding to a predetermined distance between the torch and the work piece surface, and device for providing a signal to compensate the signal portion from the discriminator circuit in response to a change in the capacitance due to a change in the area of the sensing surface of the sensing electrode projected on the surface which otherwise would cause a further false positioning of the torch.

Method of submerged arc welding high tensile strength steel having trace elements of vanadium or niobium

Abstract: Steel is welded by submerged arc welding techniques using a steel wire comprising 0.2-2.5% Mn, 0.002-0.05% B and one or more of 0.005-0.5% Ti, A1 and Zr and optionally a flux composition comprising a non-metallic flux powder and a metallic powder. The metallic powder contains 5-75% Fe, less than 5% Si and less than 10% Mn.

Welding and forming method

Abstract: A forming method in which members are forced together at an interface by causing parallel currents to flow in adjacent conductors, thereby forcing the conductors toward each other in a direction generally normal to the interface.

Welding stud and method

Abstract: A welding stud having a cylindrical welding end with a continuous annular peripheral edge surrounding a centrally axial recess, the weldable end and the metal sheet to which it is to be attached being brought together in a substantially parallel relationship, whereby a ring discharge of the arc is effected along the annular edge.

Welded box-type structural member

Abstract: A welded box article, such as, a girder, column, beam, etc., comprising top, bottom, web and diaphragm or reinforcing plates connected by ''''flat'''' welds, that is, by welds formed on the top side of a flat or horizontally positioned member and a method of constructing such an article by welding diaphragm plates to top and bottom plates with the top plate inverted and both plates flat; subsequently positioning the subassemblies thus formed on separate flat web plates with one edge of the diaphragm plates resting on the web plates and welding the diaphragm plates to the web plates to form girder sections; thereafter assembling the two sections with two of the plates extending vertically and welding the adjoining flat edges; rotating the assembly thus formed 180* about its longitudinal axis, and welding the adjoining flat edges. In an alternative method a different web plate is first welded to each of the flat top and bottom plates.

Welding power source

Abstract: A power source for a welding machine wherein, in one embodiment, both the arc voltage and current are sensed and the frequency of a pulse train, which is integrated to produce the arc signal, is varied in accordance with the sensed voltage and current. In one embodiment, a capacitor is periodically semi-discharged through a switching device, such as an SCR. The resulting voltage pulse train is integrated to produce the welding signal. In another embodiment, two capacitors are alternately semi-discharged through separate current paths which each include a switching device, such as an SCR, and a common primary winding of a transformer by shifting the SCR''s from their conductive to nonconductive states and vice versa. The transformer has two secondary windings one of which provides a high voltage, low current output and the other of which provides a high current output. Both outputs are integrated and combined to produce the welding signal.

Pulsed arc spray welding in a narrow groove

Abstract: A process for multi-layered spray arc welding using a gas shielded consumable electrode which comprises: preparing the welding edge of each of a pair of plate members such that when said members are placed into welding alignment, the combination of their prepared edges will together form an I-shaped or V-shaped welding line groove between said members, placing said plate members into welding alignment so as to form said welding line groove, and spray arc welding said plate members along said welding line groove with consumable electrode in the presence of a shielding gas by passing a welding current having a rectangular waveform through said electrode to said welding line, such that at recurring intervals, a welding arc having a current density of from 100 to 300 amp/mm2 is established between the tip of said consumable electrode and said welding line groove for a period of time of from 0.3 to 5 seconds, and extinguished for a period of time of from 0.2 to 3 seconds, such that when said arc is established, molten metal droplets are transferred to said groove, and when said arc is extinguished, the transfer of molten metal droplets is interrupted.

Apparatus for treating workpieces by laser energy

Abstract: A device for substantially increasing the efficiency, output and quality when treating workpieces by means of laser energy, particularly when welding or boring workpieces, wherein the laser beam from one single laser source is subdivided into a number of individual beams for simultaneously treating a number of places of one or more workpieces.

固有ひずみの概念による溶接残留応力および溶接変形の解析法:溶接残留応力および溶接変形の解析(第1報)

Abstract: A fundamental theory for the analysis of residual welding stresses and deformations based on the inherent strain distributed along the welded joint is presented. The first part of this paper deals with a general solution to a two-dimensional inherent stress problem which is a special case of the inherent stress theory presented by the author in a previous work. In the welded structures, the inherent strain is commonly created within the narrow strip-like region which encloses a welded joint. Therefore, the analysis of residual stress due to welding can be simplified using a model in which the inherent strain is assumed to be distributed on a line. In this case, the characteristics of the idealized inherent strain may be expressed by the intensity of the distribution. The concept of the inherent shrinkage of welded joint is introduced through the longitudinal and transverse components of this intensity of the inherent strain.The second part is concerned with the analogy between the two-dimensional inherent stress problem and the inherent deflection problem of a plate. A general solution to the inherent deflection of an elastic plate is directly obtained from this analogy by introducing the inherent curvature corresponding to the inherent strain. The inherent welding deformation is therefore defined as the combination of the inherent shrinkage and the inherent warping. In this paper, the inherent welding deformation is represented by six basic components, i.e. longitudinal shrinkage, transverse shrinkage, staggering; longitudinal warping, transverse warping and twisting. They are schematically illustrated in Fig.7.In the last part, an example of the inherent strain distribution along a butt welded joint is presented. This was recalculated by the author from the theoretical results of thermo-elastoplastic analysis of transient welding stress carried out by Prof. I. Tsuji of Kyushu University.

Switching arrangement for the stabilization and ignition of welding arcs and the like

Abstract: A switching system for the stabilization of alternating-current welding arcs and for the ignition of alternating-current or direct-current welding arcs in which the ignition or stabilization current pulse between electrode and workpiece or between two electrodes is transmitted through a capacitor and at least one semiconductive controlled rectifier (SCR or thyristor) is provided in the discharging circuit of the capacitor. The gate of the controlled rectifier is triggered by a control circuit synchronized with the current source and including a voltage-responsive switching element in circuit with a control capacitor. The voltage-responsive switching element is a DIAC-type trigger diode whose output is connected directly i.e., via only ohmic impedance) with the control electrode or gate of the controlled rectifier.

Welding by high frequency current penetration

Abstract: Methods and apparatus for welding together portions of a metal strip or strips and using high frequency current which penetrates into the metal comprising holding the portions closely adjacent, causing the current to flow in the same direction along both portions and to flow in the opposite direction along a proximity conductor extending along and in close proximity to the portions, and when welding temperature has been reached, forging the heated portions together.

Friction welding of aluminum and ferrous workpieces

Abstract: A method of joining together an aluminum workpiece and a ferrous workpiece by relative rotation of the workpieces while the workpieces are forced together at mutually engaging parallel, planar surfaces. The surfaces are thereby frictionally heated, and sufficient axial pressure is applied to the workpieces to pressure weld them together at the interface of the planar surfaces using an amount of rotational, kinetic energy input to the weld area in the range of about 3,500 to 5,500 pounds per square inch of weld area. The compressive yield strength of the aluminum alloy workpiece at the temperature to which the planar surfaces are heated by the rotational energy is such that the amount of metal of the aluminum workpiece radially displaced at the interface is less than 10 percent of the weld area.

Method of reinforcing the wall of a thermo-formed article

Abstract: AN IMPROVEMENT IN THE PROCESS FORDRAWING A SHEET OF THERMOPLASTIC, SYNTHETIC RESIN TO FORM A SHELL-LIKE SHAPED ARTICLE OF A TYPE WHICH WILL HAVE WALL PORTIONS EXCESSIVELY THIN AS A RESULT OF THE NORMAL DRAWING AND STRETCHING OF THE PLASTIC SHEET TO FORM THE ARTICLE. THE SHEET ISTHICKENED BEFORE IT IS DRAWN BY THE ADDITION OF SMALL PLASTIC PARTTICLES AT AREAS WHICH WILL FORM THE EXCESSIVELY THIN WALL PORTIONS OF THE ARTICLE AFTER IT IS DRAWN. THE PLASTIC PARTICLES ARE MELTED AND WELDED INTO THE SHEET WHILE IT IS BEING HEATED FOR THE DRAWING OPERATION, A SOURCE OF RADIANT HEAT BEING NECESSARY TO EFFECT THIS MELTING AND WELDING OF THE PARTICLES TO THE SHEET WITHOUT OVERHEATING THE SHEET.