Showing papers on "Electric resistance welding published in 1973"

Welding helmet with eye piece control

Abstract: A protective welding lens assembly is shown, as for use in the eye piece of a welding helmet, utilizing a liquid crystal together with an electrical circuit which applies a suitable electrical potential to the liquid crystal to change the same from a uniform light transmitting condition to a uniform approximately opaque condition of very small light transmission solely in response to approach to the welding electrode close to the workpiece to be welded.

Disposable resistance welding electrode

Abstract: This invention relates to a new type of resistance welding composite electrode which is disposable utilizing an inexpensive metal or alloy having good electrical and thermal conductivity as a holder, and a metal or alloy also having good electrical and thermal conductivity and in addition good strength at resistance welding operating temperatures for the insert tip.

Deep narrow gap welding torch

Abstract: A welding torch adapted for welding deep narrow gaps wherein shielding gas diffusers fit inside the welding groove, a plastic liner is placed deep inside the torch so electric contact between the filler wire and contact tube is close to the exit, and a zirconia oxide insulation prevents torch contact with the gap walls.

Welding apparatus and method

Abstract: A method and apparatus improvement is disclosed for welding an elongated seam between adjacent metal plates with a plate crawler type welding unit that tracks the seam and that includes a leading or tracking portion positioned substantially in advance of a trailing or welding portion A guide plate structure having an elongated slot is disposed in abutting relation to the metal plates with the slot aligned with the weld seam The welding unit tracks onto the guide plate structure to permit completion of the seam weld The guide plate structure is adjustable in effective thickness to effect a correspondence with various plates to be welded and is carried on a support means that permits independent three axis movement of the guide plate structure to select positions and transportation of the guide plate structure and supported welding unit between spaced welding sites

Deep penetration welding using lasers

Abstract: A TEMoo mode laser beam is focused on a material to be welded to a power density sufficiently high, depending upon the material of the workpiece, so that deep penetration welding occurs producing a weld having a depth-to-width ratio substantially greater than 1. To initiate the weld, the incident power density and power must be sufficiently high to overcome the relatively high reflectivity of metallic workpieces. With relative movement between the workpiece and the beam, seam welding can be performed, as well as lap welding and blind welding.

Method for welding iron steel and nonferrous alloy

Abstract: In welding iron, steel, and nonferrous alloys, the wire feed is changed periodically and in synchronism with periodic changes of the electric welding current to establish a previously defined relation between the welding current value and the arc length. The welding current is varied between one producing a spray transfer arc and a current just maintaining the arc.

Tool for interconnecting sheet webs by welding

Abstract: A tool essentially comprising two opposite jaws supporting means to clamp, cut and weld together foil webs. The cutting means is supported on one of the jaws whereas the heating means, and thus the welding surfaces, are provided on the opposite jaw, said welding surfaces being divided by an element having considerably less heat conductivity than the surrounding material forming the welding head proper and having a groove formed therein in which groove the cutting means is received when the jaws are brought into contact with one another during the welding and cutting operations. The arrangement provides for quick and reliable welding and cutting of foil webs without the risk of the foil adhering to the warm welding surfaces and without the need of having to protect these welding surfaces to avoid such adherence. The arrangement likewise enables accurate temperature control at the welding points.

Fluxes and slags in welding

Abstract: The complex welding technology of today demands an understanding of the formulation, manufacture, performance and use of welding fluxes. The volume of fluxes used in covered-electrode, submerged-arc, flux-cored wire, electroslag, brazing and oxyacetylene techniques, has grown to a total of probably over 400 million pounds per year in the United States. The fact that in the U.S. today the covering on coated electrodes averages approximately 25% of the 600 to 700-million pound annual production is an indication of the importance of welding fluxes. The technology leading to proper flux formulation has been little understood. It is hoped that a presentation of some of the principles of welding flux technology will provide an appreciation of improved quality of weld metal obtained through slag/metal reactions. The choice of compounds and the exact formulation in the preparation of a flux will depend upon many factors, including both technical and production economies.

Pipe welding procedures.

Abstract: A standard reference for decades, this new edition of Pipe Welding Procedures continues to reinforce the welder's understanding of procedures. Drawing on his extensive practical and teaching experience in the field, the author describes in detail the manipulating procedures used to weld pipe joints. You will find useful information on heat input and distribution, essentials of shielded metal-arc technology, distortion, pipe welding defects, welding safety, essentials of welding metallurgy, and qualification of the welding procedure and the welder.Look for new or expanded coverage of: Root Bead--Pulse Current--Gas Tungsten Arc Welding Shielded Metal Arc WeldingElectrode Welding Steel for Low Temperature (Cryogenic) Service Down Hill WeldingHeavywall and Large Diameter Welding Metallurgy Weld Repair"

Vertical welding of heavy aluminum alloy plates

Abstract: A system for welding large aluminum alloy plates in a single vertical pass by the gas metal-arc (GMA) process wherein the technique comprises spacing square butt edges of the plates about three-fourths inch to form the welding gap; oscillating between defined dwell limits a welding electrode across the gap at comparatively high rate to deposit thin layers of weld metal, and confining the weld metal by dams having facing surfaces of molded high-density electrographitic material machined to high finish respectively. The dams together with the welding head are moved vertically upward at a smooth, uniform rate to preclude any objectionable jerking movement of the facing surfaces.

Forge welding with induction coil heating

Abstract: Two adjacent re-entrant surfaces of metal parts to be welded together, at least one of the parts having metal extending in a direction away from an edge of its surface, and the metal immediately adjacent to such surfaces are heated to forge welding temperature by an induction coil supplied with an electric current having a magnitude and frequency for a time which will cause such heating without significant melting of the metal or over-heating and consequent damage to the remainder of the parts and after the forge welding temperature is reached, pressure sufficient to forge weld the parts together at such surfaces is applied to the parts.

Through-insulation welding method and apparatus

Abstract: A weld is made between an insulated wire and a terminal by pressing the wire against the terminal with an electrode, applying ultrasonic vibrations to the electrode to scrub away insulation so that electrical contact is made between the central conductor of the wire and both the terminal and electrode, and then applying a welding current through the electrode to flow through the wire and terminal to weld them together.

Method of plasma-MIG-welding

Abstract: A method of plasma-MIG-welding in which welding is carried out with the electrode and the welding wire connected to the positive terminal; by varying the current in the welding wire, a variation of the character of the MIG-arc and of the way of material transfer are obtained; at low current in the welding wire, a MIG-arc with a contracted cylindrical shape and a concentrated material transfer is obtained; at high current a rotating MIG-arc and a controlled, spread material transfer are obtained.

Automatic resistance welder

Abstract: The present invention relates to an automatic resistance welding apparatus for securing insulation material to air conditioning ducts by means of headed metal clips or pins advanced through the insulation material and welded to the ducts The apparatus includes a grounded support surface on which the metallic duct material is mounted and a welding head mounted on a guide rail in spaced parallel relation to the support surface The welding head assembly includes a welding electrode shiftable toward and away from the surface An operator handle is provided on the welding head, manipulation of the handle being effective to shift the welding head along the rail and, when the head achieves a selected position, to trigger a welding cycle The apparatus is characterized by a brake assembly interposed between the rail and the welding head assembly, activation of the apparatus through a welding cycle being preceded by energizing of the brake assembly whereby the position of the welding head relative to the rail is fixed in advance of movement of the weld clip into contact with the insulation or workpiece, and is maintained in such fixed position during formation of the weld

Welding electrode structure and filler wire mechanism for an automatic welding apparatus

Abstract: In an automatic welding apparatus wherein the welding electrode is to move longitudinally in a prescribed path to produce a weld bead upon a workpiece, the welding electrode and welding electrode housing being pivotally mounted in respect to the welding apparatus housing, a shaft interconnecting the welding electrode housing and the welding apparatus housing, the shaft being movable in predetermined increments to effect precise angular movement of the welding electrode housing with respect to the welding apparatus housing, a filler wire mechanism being universally mounted in respect to the welding apparatus housing, a portion of the filler wire mechanism being pivotal along with the welding electrode housing.

Process for out-of-position welding

Abstract: This invention concerns automatic and semi-automatic welding by means of an electric arc under a protective atmosphere of a gas, using a continuous metallic tubular flux core-type electrode with a particular composition of the core. The fluxing ingredients produce a slag of unusually high viscosity at, and just below, welding temperatures.

Multi-head resistance welding apparatus

Abstract: The invention relates to resistance welding apparatus for simultaneously attaching pins or clips to a metallic substrate carrying a batt of insulation and to a method of effecting such attachment. A support surface is provided across which the substrate is shifted by frictional drive means. Welding heads having moveable electrodes are disposed above the composite substrate and insulation batt. Pins or clips are automatically fed to the electrodes and driven through the insulation batt and welded to the substrate. A moveable connection between the pins or clips and electrodes permits relative movement in the direction of the composite.

Structure for and method of mesh welding

Abstract: A plurality of cylindrical welding guns for welding wire mesh in contact with each other staggered on each side of a linear transversely extending member of the wire mesh having off-center electrodes secured thereto with welding portions engageable with the wire mesh and insulated fixed electrodes positioned beneath the welding guns and wire mesh, which welding guns and electrodes secured thereto in conjunction with said fixed electrodes are adapted to produce welds at any of 2, 3, 4 and 6 inch spacing on simultaneous actuation of all of the welding guns through a single actuating media circuit having a single intake and a single outlet manifold, with all welding guns electrodes active as either welding electrodes or to provide a return circuit for welding electrodes during welding operations at all spacings, said welding guns being constructed and arranged to permit location of all transformer structure therefor on one side of the welding guns without special clearance structure.

Contact nozzle for a continuous arc welding electrode

Abstract: A contact nozzle for supplying welding current to a continuous, fusible arc welding electrode in which a pneumatic cylinder or other resilient means maintain a contact member in engagement with an electrode backed on the opposite side by a wearresistant, electrically nonconducting or poorly conducting backing member.

Method for control of welding apparatus

Abstract: A system for improving the quality of a bond obtained from an ultrasonic welding apparatus includes a resistance measuring circuit for monitoring the electrical resistance between the wire to be bonded and the bonding head. The welding apparatus is automatically de-activated upon an increase in said resistance, the increase being indicative of bond formation. De-activating the bonding apparatus immediately following bond formation prevents the application of further ultrasonic energy from weakening the bond.

Welding apparatus with consumable welding wire

Abstract: In welding apparatus employing a consumable welding wire, the wire feed rate and the welding source voltage, as parameters of the required welding energy and for the proper functioning of the welding process, should be precisely adapted to each other if a weld of high quality is to be attained under varying welding conditions. The invention provides a solution for this by measuring the wire feed rate as a parameter and by controlling control devices in the welding circuit by means of this parameter. This considerably simplifies adjustment of the welding equipment, thus enabling remote control, for example, from the welding torch, also during welding. An advantage is that the operator can introduce small, continuous variations of the welding voltage during welding.

Pressure operated control for resistance welding machines

Abstract: Pressure operated control for resistance welding machines in which a fluid pressure cylinder and piston operates the pressure electrode and is connected to a source of fluid under pressure. The pressure electrode is pressed into engagement with a workpiece over an anvil electrode. The control is such that the electrodes are not energized until the pressure of the pressure electrode on the workpiece reaches a predetermined pressure.

Development of the weld-braze joining process

Abstract: A joining process, designated weld-brazing, was developed which combines resistance spot welding and brazing. Resistance spot welding is used to position and aline the parts, as well as to establish a suitable faying-surface gap for brazing. Fabrication is then completed at elevated temperature by capillary flow of the braze alloy into the joint. The process was used successfully to fabricate Ti-6Al-4V alloy joints by using 3003 aluminum braze alloy and should be applicable to other metal-braze systems. Test results obtained on single-overlap and hat-stiffened panel specimens show that weld-brazed joints were superior in tensile shear, stress rupture, fatigue, and buckling compared with joints fabricated by conventional means. Another attractive feature of the process is that the brazed joint is hermetically sealed by the braze material, which may eliminate many of the sealing problems encountered with riveted or spot welded structures. The relative ease of fabrication associated with the weld-brazing process may make it cost effective over conventional joining techniques.

Method and means for controlling adjacent arcs

Abstract: This invention relates to arc welding apparatus and describes a method and means for producing welds in which the metal in the weld area is of higher ductility than has been produced in welds made with conventional welding apparatus. Two welding torches are utilized one closely following the other. A magnetic field is directed across the arc formed by each torch so as to produce a force which is directed opposite to the force created by currents flowing in the same direction through the adjacent arcs. This latter force would otherwise cause the arcs to move towards each other and be erratic and inconsistent in their effect.

Damped support screen for catalytic converter

Abstract: Support screens for retaining particulate catalyst in a catalytic converter are made highly resistant to fatigue failure which is caused by vibration from exhaust gas pulses. The screens are strengthened by welding formed support wires at a single center point to the downstream face of each screen. The wires are integral with the screen only at its center. Other portions of the wires are positioned in recesses in the housing walls where they prevent axial movement of the screens. The portions of the wires within the recesses are free to expand or contract independently of the material of the screen. The limited degree of connection between the wires and a screen prevents the wires and screen, which have different natural frequencies, from vibrating as a composite unit. Furthermore, any tendency toward separate vibration of the wires and screen is damped due to the contact between the wires and screen. By embossing the screen at its center and placing a metal disk on the side of the wires opposite the screen it is possible to use high energy discharge resistance welding techniques to achieve a screen-support composite having much greater deflection resistance than is possible by ordinary welding.

Weld rod containing manganese

Abstract: A cored wire welding electrode for welding cast iron having an outer sheath made of nickel or a nickel-iron alloy and a powedered core composition containing copresent metallic magnesium and graphite and slag-forming ingredients along with special amounts of manganese. The electrode is particularly useful for open arc welding wherein a high strength weld deposit is required.

Electronic protection device for spot-welding equipment

Abstract: If the contact resistance of materials being spot-welded is too high, due to surface contamination, destruction of the specimen may result because of excessive heating by the welding pulse. A device is described which measures the contact resistance electronically, and so indicates when welding conditions are suitable.