Showing papers on "Submerged arc welding published in 1973"

Instructional apparatus for underwater welding

Abstract: Instructional apparatus for use in gaining experience in underwater welding having submerged welding facilities in a water container provided with a below-water level viewing window and a pair of rubber gloves secured to the container wall below water level. The water includes a small quantity of acid which reacts with and renders non-obscuring suspended opaque particulate unavoidably generated during welding. Putting on and taking off the gloves is facilitated by one of several techniques for temporarily relieving the hydraulic head on the gloves. Welding is carried out on a workpiece clamped to a support readily adjustable to a desired submerged position.

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.

Metal halide discharge lamp having an arched arc tube

Abstract: The arc tube of a metal halide arc discharge lamp has electrodes at each end thereof and contains a fill including mercury and a metal halide. The arc tube has an arch shape so that, during operation of the lamp in a horizontal position, the arc discharge is substantially equidistant from the walls of the arc tube.

Electrode for vertical-up open arc welding using molding shoes

Abstract: A cored-type welding electrode for vertical-up welding using molding shoes to hold the molten metal in position, using an open arc which does not require an externally-supplied shielding gas and which permits very high linear welding speeds. The core materials include a metal fluosilicate capable of breaking down in the heat of the arc to produce: a gas in sufficient volume to shield the arc from the atmosphere and a slag forming ingredient; and, other slag forming ingredients including the metal oxides and the alkali metal fluorides in a critical volume such that the total slag forming ingredients do not exceed six percent of the total electrode weight and the oxides are present in quantities at least greater than the fluorides. The self-shielded electrode further permits the use of active deoxidizers in quantities of under 0.5 percent.

Process of adding alloy ingredients to molten metal

Abstract: A process and an apparatus for making alloying additions to molten metals. The process consists of providing the material to be added in the form of strip, wire or rod: placing this material in close proximity to the molten metal to which the addition is to be made; and flowing a high current through the material to be added and the molten metal forming an arc between the molten metal and the material to be added. The heat of the arc melts the addition material which is then driven through the arc into the molten metal.

Submerged-arc welding machine

Abstract: A submerged-arc welding machine comprises a welding head pivoted to a frame of the machine so as to be rockable across the seam of a workpiece being welded, and a vertically movable oscillation mechanism provided with an eccentric cam engaging the welding head for causing the welding head to rock across the seam as the cam rotates Further included is an oscillation amplitude adjusting device for moving the oscillation mechanism as well as the cam vertically, whereby the axis of rotation of the cam is adjustable relative to that point on the frame about which the welding head pivots to adjust the amplitude of the rockable movement of the welding head

Submerged arc welding process for very low-temperature steel and welded product

Abstract: A submerged arc welding process forming a welded steel joint consisting of said steel pieces joined by weld metal having superior impact resistance at low temperatures, said weld metal consisting essentially of up to 0.1% carbon, less than 0.4% silicon, between 1.2% and 1.7% manganese, between 0.08% and 0.5% molybdenum, between 0.02% and 0.05% titanium, between 0.0012% and 0.004% boron, up to 4% nickel, and less than 0.045% oxygen. The process utilizes specified low-temperature steel base metal which is to be welded; specified welding electrodes; and a flux.

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.

Welding method and materials

Abstract: Methods and materials for submerged arc welding for obtaining a high toughness welded metal containing titanium and boron by using a flux cored wire composed of a steel sheath and a core containing titanium and boron with the addition of a metal fluoride.

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 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.

Method of and apparatus for the submerged arc surfacing of metallic work pieces

Abstract: Method of and apparatus for the submerged arc surfacing of metallic work pieces with metal strips melting in an electric arc while forming welding beads of more than 75 mm in width. The strip electrode is connected to the pole of a direct-current source; during the melting process the electrode is accompanied by a stationary magnetic field. By means of such magnetic field in the region of the edge zones of the strip electrode the carriers of positive charges in the arc are deflected toward the direction of welding travel so as to slope outwards, said edge zones being approximately one-twentieth to one-fourth of the strip electrode width. By use of the invention the width of the surfacing layer is increased by 2 to 15 mm, as compared with the bead width obtained with apparatus in which no influence upon the arc is exerted by the magnetic field.

Electrode and flux combination for submerged arc welding

Abstract: In order to apply the submerged arc method of welding to a medium-carbon, Ni-Cr-Mo-V steel, and obtain a weld deposit which can be heat treated to provide a yield strength of 160-180 ksi along with a reduction in area of at least 25 percent and an impact resistance of at least 15 ft/lbs. at -40*F, an electrode wire having no more than 0.04 percent of silicon is utilized with a neutral welding flux having a residual percentage of manganese and from 1.5-3.0 percent of silicon to insure the proper deoxidation of the molten electrode. The flux also includes about 0.30 percent carbon for replacing that portion thereof lost from the electrode wire during the formation of the weld deposit.

Method of welding metals under water

Abstract: The underwater welding of metal surfaces using a plasma arc, wherein the plasma arc, plasma gas and weld part are sealed with a layer of water glass.

Method and apparatus for forming transverse welded seams between vertically oriented workpieces

Abstract: The welded seams are formed between facing edges of vertically oriented plate sections by submerged arc welding. The bottom edge of an upper section is formed with intersecting bevelled faces defining a V-shape nose in cross-section, and the upper edge of a lower thick plate section is formed with intersecting sloping faces defining a V-shape upwardly opening notch in cross-section. The sections are placed with the apices of the V-shaped cross-sections in substantial alignment vertically to define opposite facing welding grooves having a common welding groove root. The faces defining the welding grooves are arranged at angles such that the welding groove sides diverge outwardly and upwardly from the root. Molten weld metal is progressively deposited along the welding grooves by submerged arc welding while the welding powder is supplied to the grooves both before and behind the pool of molten weld metal. The apparatus includes a welding wire feed guide, contact jaws for conducting current to the welding wire, a conductor for connecting the contact jaws to a source of welding current, and a powder feed pipe in the form of an inverted Y which is fixedly connected with the welding wire feed device. The outlet openings of the powder feed pipe are arranged, respectively, before and behind the contact jaws in the direction of weld formation. A pressure gas may be supplied to the powder feed pipe in advance of the Y junction.

Plasma Arc Welding for Thick Plate (Report 1)

Abstract: This study was conducted as a preliminary research for further development of some plasma arc welding methods for thick plate above 10 mm.The large plasma torch and the control equipment designed to be proof against up to 1000 A with straight polarity connection have been fabricated especially for this study in our laboratory. With the ues of these equipments a series of experiments was carried out on the arc characteristics, welding conditions and welding sound.Conclusions obtained are summarized as follows:1) Thermal efficiency of plasma arc is in range of 53-60% and its heat losses to cathode, nozzle, shield cover and the other parts are 2, 20, 9-11 and 7-11% respectively at 500 A arc current.2) The Va-I (arc voltage vs. arc current), Va-Qp (arc voltage vs. plasma gas flow rate), and Va-la (arc voltage vs. arc length) characteristics of plasma arc at 300-500 A have been obtained as linear relationships whose slopes are in range of 0.02-0.05 V/A, 0.4-0.6 V/l/min and 0.4-0.6 V/mm respectively.3) The optimum welding conditions for plasma arc welding of 6, 8 and 10 mm thick mild steel plates have been evaluated in connection with welding speed, welding current, and arc constricting wall length of nozzle.4) In plasma arc welding of 16 mm thick mild steel plates, weld beads were produced as burn through or incomplete penetration beads. When the plates were backed up with copper plates, unstable plasma arc and sometimes series arcing occured and resulted in a defective bead.5) The frequency characteristic evaluation of plasma arc welding sound reveals that welding sound consists of mainly 300 Hz frequency as fundamental tone and its higher harmonics due to current pulsating (300 Hz frequency) in full wave rectification, and also that frequency characteristic is subject to the influence of welding condition mainly in above 2kHz frequency range.

Method of submerged arc welding of high tension steel workpieces

Abstract: Submerged arc welding of high tension steel workpieces by using bonded flux capable of generating at least 7 percent by weight of carbon dioxide gas during welding operation and producing slag with a basicity B L of not smaller than 1.0, in conjunction with a welding wire capable of providing alloying elements to weld metal, so as to produce weld metal having a high toughness and a high crack-resistivity.

Improving weld bead toughness - by hot deforming to flatten bead

Abstract: Directly after welding by gas protected or submerged arc welding, the bead is deformed whilst its central temp. is 600-950 (pref. 700-850 degrees C) in one or several steps by up to 50 (pref. 10-30)%. The bead is flattened or in the case of fillet or build-up welding a concave shape is produced. Deformation is effected by rolling forging, drawing or processing. The weld produce in molten state but prior to mixing with the base material pref. comprises 0.03-0.06% C; 0.3-0.45% Si; 1.6-2.0% Mn; 0.02% P; 0.02% S; and one or more of 1.5% Mo, 0.06% Nb; 0.2% V and 0.03% N2. The weld has better strength, toughness and improved notch impact transition temp.

Apparatus and method for arc working work-pieces with a rotating arc

Abstract: This invention relates to an apparatus for performing plasma arc welding by a process in which the plasma arc travels about a closed path or orbit on the work-piece. More particularly, the invention provides a plasma arc welding apparatus useful for performing butt welded joining of cylindrical work-pieces, such as pipes and rods, and for welding tubes to tube sheets. The invention utilizes an annular slot nozzle which is operated with a gas for maintaining a plasma arc, and a generally ringshaped electrode positioned in circumferentially opposed relation to the weld path. A magnetic field interacting with the plasma arc between the electrode and the work-piece causes the arc to travel around the weld path to perform welding therealong.

Flux supply device for a submerged arc welding

Abstract: A head of a welding machine is disposed within pipe to be welded according to a submerged arc welding method. The head houses a small flux supply hopper connected through a flux supply duct to an outside master hopper for supplying a flux to the small hopper. A supply of flux is controlled by a control valve controlled by a flux level detector mounted to the small hopper, so that the amount of flux accumulated within the small hopper is maintained at all times constant.

Welding together conductors - whereby one conductor is covered with insulating material

Abstract: Electric conductors, one of which carried a layer of insulating material, are welded together between two welding electrodes by heating the latter until the insulating layer melts and then welding the two conductors in contact with each other, when the welding current pulse is automatically released.

Studies on the underwater CO2 arc Welding method with a curtain nozzle

Abstract: CO2 arc welding which is employed in the wet underwater welding has the following advantages.(1) The process is simple to operate.(2) In the safety aspects, the lower open voltage characteristics of arc welder is particulary helpful to avoid electric shock.(3) Welds can be made in all positions.But, in conventional wet underwater CO2 arc welding, nozzle-base metal distance was not more than 4 mm, therefore the welding operation was very difficult.We studied the following system that was called curtain water type underwater CO2 arc welding aimed to improve this problem. In the dual flow system which we used, curtain water was introduced from the outer nozzle. By this system we could take nozzle-base metal distance about two times longer than that for conventional shielding system. As the results of radiographic examination, no difficulty was found to obtain the welds without blowholes. At the first step to develop this process, we report experimental results of down hand position butt welding for mild steel.

Controlled pressure consumable electrode vacuum arc remelting process

Abstract: Manganese or other high vapor pressure elements are prevented from volatilizing during vacuum arc remelting by introducing a small flow of inert gas into the mold and varying the rate of exhaust of gases from the mold from a maximum value when the arc zone is at the bottom of the mold to a minimum value when the arc zone is at the top of the mold so as to maintain a pressure in the arc zone higher than the vapor pressure of the volatile element.

Furnace plant for the drying or baking of coated arc welding rods

Abstract: A tunnel furnace plant for the drying or baking of coated arc welding rods in which the welding rods are suspended freely from straight carriers extending transversely to the direction of advancement through the furnace, each of said carriers carrying a row of welding rods. The plant also includes automatic equipment for fitting the welding rods to the carriers.