Showing papers on "Gas metal arc welding published in 1970"

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.

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.

Automatic control mechanism for plasma welder

Abstract: An automatic control device for plasma arc welding by use of a plasma torch fitted with a cathodic electrode and a gas blow nozzle, said torch being movable relative to a welding stock which is arranged as an anodic electrode, said device being characterized by the provision of a photoelectric sensor arranged to measure the inclination angle of the tail flame part of the plasma arc emerging from the backside of the welding stock while the welding operation is going on, the electric output signal from said sensor being fed to an electronic control circuit adapted for control of any one or more of the welding parameters such as the relative travel speed between the torch and the welding stock, the rate of plasma gas supply and the rate of the welding current.

Welding control arrangement

Abstract: An apparatus for controlling the application of weld metal in electric calarc welding includes a mechanical scanning device upstream from the welding torch. The scanning device penetrates into the welding groove and measures at least one physical dimension thereof which is converted into signals for controlling the welding material feed.

Welding gun trigger control circuit

Abstract: A MIG welding gun trigger control circuit in which the welding gun trigger is employed to control the supply of welding gas, welding current, and welding wire feed to the gun, with the arrangement being such that to start the welding the operator presses the trigger to obtain a pre-welding gas purge without welding current or wire feed, and after the pre-welding gas purge is completed, the trigger is released to start the wire feed and provide welding current as well as continue the shielding gas flow. If the arc forms, the operator proceeds and completes the weld without having to hold the trigger switch closed, and when the weld is complete, the operator again presses the trigger switch to stop the wire feed but provide continued gas flow for post-welding purge, this action setting into motion a timer circuit that briefly continues welding current supply for stub burn off. After post-purge, release of the trigger switch shuts off the welding system and re-sets the system for the next welding operation. If the arc fails to form during the start cycle or if the arc or the weld current is broken during the actual weld, the control system automatically shuts itself off.

Apparatus and method of increasing arc voltage and gas enthalpy in a self-stabilizing arc heater

Abstract: The method includes admitting gas to be heated at a high velocity into an arc chamber through a narrow gap between spaced electrodes while maintaining across the electrodes a system or backup voltage sufficient at all times to cause electrical breakdown in the narrow gap between electrodes, while producing in the arc chamber a magnetic field having a preselected configuration to produce a beneficial effect or effects on the arc. The arc is periodically elongated by the high velocity gas until it attains such a length that the voltage required to sustain the arc exceeds the breakdown voltage of the gap whereupon the arc returns to the gap momentarily only to be blown out and elongated again. Gas is brought to the vicinity of the outside of the gap through a plurality of tangentially extending slots at spaced intervals around the entire periphery of the gap, whence it passes through the gap, the gas passing through the gap having a radial component and a tangential component. The high tangential flow component provides sufficiently large gas velocity to blow the arc from the electrode gap at a greatly reduced mass flow rate which may be of the order of one-fourth the flow rate which would be required if gas were admitted solely in a radial direction through the gap. The resulting decrease in the volume of gas to be heated results in an increased enthalpy imparted to the heated gas which may be of the order of five times that which can be obtained by purely radial gas admission. A higher arc voltage, results in a greatly improved power factor, and resulting decreased arc current results in an improvement in electrode lifetimes. Centrifugal effects in the arc chamber together with the influence of the magnetic field on the arc establish conditions wherein the arc column virtually follows the center line of the heater. Apparatus is provided for bringing gas to the gap to produce the aforementioned tangential flow coponent, and generate the magnetic field.

Art of casting metals

Abstract: An inert gas welding torch is used to create plasma by directing one or more discrete high velocity jet gas streams into a welding arc between the electrode and the workpiece. The plasma stream is controllable with regard to energy content or location by varying the amount or direction of the inert gas flow. The plasma stream is insensitive to variations of arc length, and permits abnormally high current densities in the electrode. When used with consumable electrodes, the invention is useful for casting as well as for deep welding heavy plate materials in a single pass.

Method and apparatus for welding an overlay on a metal base

Abstract: A method and apparatus for welding an overlay on a metal base. The welding apparatus contains a supply of granular flux which feeds through a nozzle and covers the weld. An inert gas is introduced to the flux supply to purge it of air. The gas discharges through the nozzle and assists in protecting the weld. Particularly useful for welding an overlay of a nickel tantalum alloy.

Welding by electron bombardment

Abstract: Electron beam welding apparatus wherein means are provided for welding a joint sealed by a sheet of foil and thereafter depositing a plastic product on the weld head to prevent contamination.

Device for electrical protective gas welding

Abstract: An electrical protective gas welding device for seam welding a plurality of layers together with different thickness wires mounts both the wire supply devices and the corresponding torches on the same electrical equipment housing for sequential operation thereof.

Thermionic insulated arc welding gun

Abstract: Improved means of insulating that portion of an air cooled arc welding gun which extends between the handle portion and the head portion to prevent thermionic emission dense enough to establish the conductance of welding current between it and the weldment, improved means for enclosing the welding current circuit suspended within the handle of the gun within a tube composed of insulating material to reduce the amount of heat radiated from the circuit within the handle, and improved means for suspending a highly heated welding current circuit within the handle to provide space between the wall of the handle bore and the suspended heated circuit for the circulation of cooling air therethrough. Also disclosed is the method of making the improved structure.

Resistance welding coated sheeting

Abstract: Welding current is fed, at least for one of the coated sheets, indirectly to the point to be welded by means of the sheet surface in order that an external layer remains intact and a contact established between the surfaces which have been uncovered for welding. Annular or linear edges and depressions are formed at the welding point in the sheet or on the intermediate welding pieces with the aid of stamps and/or cutting. Overcomes drawbacks encountered with conventional prior art welding machines where the outer layers of the welded sheets are destroyed by uncovering or by the fusion caused by the electrodes. Use: welding metal sheeting or elements coated with synthetic material, varnish or some other substance, such as steel, chrome-nickel steel, aluminium (anodised) or other metals.

Method of preparing metal oxides with arc gas heaters

Abstract: EXTERNAL SURFACE OF THE FRONT ELECTRODE OF THE ARC GAS HEATER. METAL OXIDES, SUCH AS TITANIUM DIOXIDE, ARE PREPARED BY VAPOR PHASE OXIDATION OF CORRESPONDING METAL HALIDES IN A REACTION SPACE SUPPLIED WITH HEAT ENERGY FROM A GAS STREAM HEATED BY ELECTRICAL ENERGY. ARC GAS HEATERS HAVING FROM AND BACK ELECTORDES ARE DESCRIBED. MAGNETIC FIELD MEANS ABOUT THE FRONT ELECTRODE ARE USED FOR PREVENTING ELONGATION OF THE ARC STRUCK BETWEEN THE FRONT AND BACK ELECTRODE AND PREVENTING LOCATION OF THE ARC FOOT ON THE

Inert atmosphere tack welder

Abstract: This disclosure relates to spot resistance welding or tack welding of edge portions of sheet material, particularly the welding of seams of containers. Means are provided for effecting gaseous flow around each of a pair of opposed electrodes with the flowing gas being preferably an inert gas and the flow being selectively one of pressure to one electrode and vacuum or partial vacuum to the other or pressure flow to both electrodes. Inert gas flow between the sheet portions being welded is also obtained.

Resistance welding and soldering of coated - sheet metal

Abstract: A current is passed through the decoated welding point of the coated metal strip to be welded to the opposite pole of an electrode. The welding current passes from this metal strip to the second metal strip through decoated inner surfaces. Pressure is applied together with the welding current and the coated outer layer of the metal strip is unharmed.

Measurement and interpretation and application of parameters important to electron beam welding.

Abstract: A study of the electron beam welding process has been initiated by several AEC contracting agencies. The purpose of this study is to define the physical properties of materials and operational features of electron beam welding machines in order to better describe the characteristics of the electron beam welding process. The various agencies and organizations which have been involved in this study have used various kinds of welding equipment and diagnostic instrumentation. The Los Alamos Scientific Laboratory has been a contributor to this program in the areas of beam diagnostics and the relationship of physical properties of materials to the resultant welds. The welding machine which has been used for all of the studies described in this paper is a 7.5

Welding paste for resistance welding copper parts

Abstract: A WELDING PASTE FOR JOING COPPER PARTS BY RESISTANCE WELDING BY COATING SUCH PARTS TO BE JOINED AT THE POINTS PRIOR TO WELDING WITH THE PASTE CONTAINING A MIXTURE OF POWDERED SILVER OR POWDERED SILVER AND A SOLDERING FLUX.

Magnetic force upset welding dissimilar thickness stainless steel tee joints

Abstract: Stainless steel sheet-to-plate tee joint resistance welded by Magnetic Force Upset Welding process, testing performance

Coated electrode for electric arc welding of steel of various structure

Abstract: The present invention relates to welding coated electrodes and is used for welding steel of various structure. The electrode comprises a rod containing carbon, silicon, manganese, molybdenum, nickel, titanium and iron, and a coating of the fluoric-calcium type.

High-frequency starting device for an electric welding arc

Abstract: A device for starting an electric arc welding torch. To the nozzle of the torch are attached two auxiliary electrodes energized by a high-frequency electric current generator through coaxial cables. There is no electric connection between the welding electrode and the auxiliary electrodes.

Method and apparatus for electron beam welding

Abstract: This invention relates to a method of welding low carbon steel using an electron beam. The portion of the workpiece being welded is located in an evacuated welding zone and a deoxidizing metal backup member is disposed in spaced relation to the joint to be welded. During welding, the electron beam vaporizes a portion of the deoxidizing metal and the release of the metal vapor aids in increasing the soundness of the weld.

Parameters Involved in the Spectroscopic Monitoring of Atmospheric Contaminants in the Tungsten Inert Gas Arc Process

Abstract: Tungsten-helium arc atmospheric contaminants spectral monitoring parameters under welding conditions, using rotating circular wedge to oscillate emission lines across exit slits

Tensioning device for flat welding layered ne - metal foils to ne metal flat shapes

Abstract: Flat welding of layered NE-metal foils to NE metal shapes, particularly to form a current passing connection, where the shape and the layered foils at the connection point are so prepared as a V-seam that the foils are connected at their sectional plane by 'lubricating' the material The connecting points are also connect by, for example, MIG welding (metal-in-gas) The weld pool at the base of the V-seam is held by a form plate which is of the same material as the parts to be welded and is arranged in a cooled adapter with low thermal conductivity

The Influence of Shield Gas Compositions on the Arc Temperature in Gas-Shielded Metal-Arc Welding

Abstract: The influence of shield gas compositions in argon-nitrogen, argon-oxygen, argon-carbon dioxide and argon-hydrogen systems on the arc temperature was studied by means of the spectral line intensity method.The findings in this work are as follows:1) The arc temperature increases slightly with an increase of welding current.2) The arc temperature does not undergo a noticeable change with arc voltage.3) The arc temperature increases with an increase in nitrogen, oxygen, carbon dioxide and hydrogen additions.The arc temperature in argon-hydrogen gas mixtures is highest, and the one in argon-carbon dioxide gas mixtures is lowest.4) The arc temperature seems to be influenced by electrode materials.

Parameters for Pressurized Inert Gas Metal Arc Welding of Aluminum.

Abstract: This study was designed to establish the significance of various process parameters in Pressurized Inert Gas Metal Arc (PIGMA) welding. Specifically, the effects of arc voltage, filler metal speed, travel speed, and chamber pressure were determined. The measured responses were arc mode and stability, weld appearance, soundness, area, width, penetration, reinforcement, and depth-towidth ratio. Using predetermined combinations of parameters, bead-on-plate welds were made on an 8 in. diameter by 1 in. wall Type 1100 aluminum cylinder. The filler metal was 0.030 in. diameter Type 718 aluminum alloy. The welding was performed in a pressure chamber with the cylinder in the horizontal-rolled position. After welding, the welds were X-rayed and visually and metallographically examined. For purposes of analysis, the raw data of each response were treated using a multiple regression analysis technique. By this technique, the variability in ratings due to each independent variable and to lower order interactions was determined. Calculated ratings were obtained for each combination of parameters. The results of the study were derived using the trends of the calculated ratings. Findings are briefly described below: Chamber pressure, in general, when increased, acts to reduce weld appearance, weld width, and arc stability and increases the depth-to-width ratio. Increased pressure shortens the arc and changes the transfer mode to short circuiting. Arc voltage, when increased from 22 to 28 v, exhibits relatively minor influence on weld soundness and appearance but did increase weld penetration and area. Travel speed, when increased from 60 to 120 ipm, decreased weld penetration, width, and cross-sectional area. ELDON D. BRANDON is with the Rocky F la t s Division. The Dow Chemical Co., Golden. Colo. P a p e r presented a t the AWS 51st Annual Meeting held in Cleveland. Ohio, dur ing J u n e 8-12, 1970. Filler metal feed speed, was the most significant factor affecting weld appearance, soundness, reinforcement, penetration, width, area, and depth-to-width ratio. The best appearing and soundest welds occurred at lower filler metal feed rates. As would be expected, the size of the weld increased with filler metal feed rate. Using criteria of acceptable appearance and soundness, the maximum depthto-width ratio (1.2:1) was obtained at 29 v. 800 ipm filler metal feed speed. 70 ipm travel, and 82 psi absolute pressure. Introduction Pressurized Inert Gas Metal Arc or PIGMA welding is a relatively new technique being used at the Rocky Flats Plant to reduce weld-metal porosity to extremely low levels when other techniques fail. Other desirable conditions, such as a narrower, more Fig. 1—Welding chamber and fixture used for PIGMA welding study Fig. 2—Close-up of torch/filler metal feeder assembly concentrated arc profile, have been realized. The PIGMA process is essentially the same as gas metal-arc welding except that the torch and workpiece are enclosed within a pressure chamber. For welding, the chamber is pressurized to some elevated pressure in the range of 20 to 100 psia. The chamber may or may not be evacuated before being pressurized. Inert gas is normally used to backfill the chamber after evacuation. However, compressed air may be used if an inert atmosphere is not required. After the desired pressure is reached, the welding proceeds in the normal manner except, of course, the operation must be carried out by remote control. The basic process and equipment have been described in more detail by Barker.* The current program was designed to establish the significance of various process parameters in PIGMA welding. Several response variables were measured to find their relationships to the basic welding parameters. Also, a wide range of variable levels was used. Thus, a set of limits was established wherein acceptable welds could be made. Experimental Materials The selected base metal, type 1100 a l u m i n u m , was c y l i n d r i c a l , 8.28 in. outside diameter by 1 in. wall by 13 in. long. 1100 aluminum is a 99% purity alloy containing very small amounts of copper, silicon, and iron. The filler metal was a 0.030 in. diameter 718 aluminum alloy. This alloy consists of 12% silicon, the balance aluminum. Before welding, the cylinder was » Barker . R.. "PIGMA Welding—A Methold for Reducing Weld Poros i ty , " Welding Journa l , 44 (1), Research Suppl. , l-s to 6-s (1965). 510-s ; N O V E M B E R 1970 Table 1—Summary of Pressurized Inert Gas Metal Arc Welding Procedure Process Base Metal Filler metal Preweld cleaning (base metal) Joint configuration Temperature control Welding position Polarity Shielding gas (torch) Chamber gas Power supply