Showing papers on "Arc welding published in 1980"

Metallurgy of Welding

Abstract: The effect of surface forces on the bonding of materials. Solid-phase welding and adhesive joining. Soldering and brazing. The joining of ceramics: microjoining. Fusion welding: processes. Fusion welding: mass and heat flow. Metallurgical effects of the weld thermal cycle. Carbon and ferritic alloy steels. Austenitic and high-alloy steels. Non-ferrous metals. The behaviour of welds in service.

Arc augmented laser processing of materials

Abstract: It has recently been found that an electric arc can be added to the interaction between a laser beam and a material surface in such a way that in welding and cutting it produces an effect similar to that from a more powerful laser. The experimental results are discussed together with an analysis of the process mechanism. In particular it appears that the arc strikes the work piece at the same interaction zone as the laser, and in so doing undergoes a contraction in width to near the same size as the laser beam. It also seems probable that some of the arc energy penetrates the laser generated keyhole. So far the experimental results have shown that arc augmentation of the laser by some 2 kW of arc power in the work piece can be achieved without unduly spoiling the high quality of the cut or weld that would be made by a laser alone of similar total power.

Pulse arc welding device

Abstract: PURPOSE: To reduce arc voltage, prevent arc breaking and stabilize the arc by increasing background current when an arc voltage detected value rises above a set value. CONSTITUTION: A pulse current waveform is supplied to the arc 6 by a pulse current source 21 and a background current source 22. At this time, the arc voltage is detected with an arc voltage detector 23 and is compared with the reference voltage of an arc voltage reference setter 24 in a comparator 25. When the arc voltage is larger than the reference voltage, a current increase command is given from the comparator 25 to the source 22 which in turn flows the current added with the current value having beforehand been corrected with a background current corrector 26 to the arc 6. Hence, when it comes to the point of the time I when the arc is liable to break in the background part, the arc voltage rises and at the same time the background current value 2 begins to lower. At the point of the time II when the arc voltage exceeds the reference voltage, the background current 2 is increased, thereby stabilizing the arc. Then, the arc voltage decreases and at the same instant the command of the comparator 25 stops. At the point of the time III, the background current resumes the original value. COPYRIGHT: (C)1982,JPO&Japio

Composite wire for gas shielded arc welding

Abstract: PURPOSE: To execute vertical up welding with high efficiency and to obtain the composite wire which has the good migratability of droplets and decreases the amt. of the spatters to be generated by specifying the grain size constitution, incorporating TiO 2 at a specific ratio into the wire and incorporating specific components at specific ratios therein. CONSTITUTION: A flux is filled in the sheath made of a steel. The grain size constitution is so specified that the particles having the grain size exceeding 149μ are incorporated into the wire at 10wt.% and the particles having 44μ grain size or below at ≤30wt.%. The TiO 2 is incorporated into the wire at 3.5W7.0wt.% of the total weight of the wire. Further, contains 0.4W1.0wt.% ZrO 2 , 0.1W1.0wt.% Al 2 O 3 , 0.3W1.0wt.% Si, 1.2W3.2wt.% Mn, 0.1W0.6wt.% Al, 0.03W0.3wt.% total of 1 or 2 kinds of Na, K:Na, K, and 0.01W0.2wt.% F. The vertical up welding is thereby executed with high efficiency and the amt. of the spatters to be generated is decreased; in addition, the working efficiency of welding is improved. COPYRIGHT: (C)1989,JPO&Japio

Automatic welding position control method, and device

Abstract: A welding method in which a pair of base metals are welded together by swinging the welding torch right and left, and a device for practicing the method. In the method, the arc current is continuously detected, and sampling pulses are formed in time slots provided by the swinging motion of the torch. The arc welding currents are sampled and held with the aid of the sampling pulses, whereby the peak values of arc currents flowing when the torch is swung right and left are detected, and the position of the torch is correctively shifted right or left according to the difference between these peak values.

Welding powder feed device

Abstract: A combination for feeding welding powder from a welding tractor for arc welding over a vertical to horizontal curved surface includes a pivotable powder vessel and a mechanism for maintaining the vessel in a vertical position.

Electrical conductor connection and method of making same

Abstract: Two improvements to the electrical conductor connection disclosed in U.S. Pat. No. 4,163,869. The first is a new and improved process for forming by means of multiple timed MIG arc welding, an electrical connection between at least two lapped aluminum conductors, wherein neither conductor member has a pilot hole, thereby eliminating preforming and alignment requirements. The improved process produces the same full penetration weld with the same highly desirable substantially cylindrical weld nugget as the process of U.S. Pat. No. 4,163,869 with a preformed pilot hole does. The second improvement is a new and superior electrical conductor connection and a method of forming same between at least two lapped aluminum conductors. The connection so formed includes a weld nugget having a substantially rectangular cross-sectional configuration at the interface. The rectangular shape of the weld nugget at the interface increases the mechanical torque capacity and the electrical conductivity of the connection.

A.C. Arc welder

Abstract: An a.c. arc welder includes a reactor between a source of a.c. power and a welding load for accumulating energy during the increase of voltage from the source. A bypass circuit is further provided in parallel to the reactor and the welding load for dissipating the accumulated energy as a welding current through the load.

Non-consumable electrode arc welding method

Abstract: PURPOSE: To obtain weld beads of uniform depth of penetration and a broad sectional shape by applying alternating magnetic fields to the arc generated from a nonconsumable electrode of which the sectional shape near the leading end part is approximately a rectangular shape, thereby oscillating the arc in the long side direction of the electrode section and controlling the shape of the weld beads. CONSTITUTION: In the sectional shape near the leading end part of a nonconsumable electrode 2, the direction approximately perpendicular to the weld line direction is made the long side of a rectangular shape section, and the width thereof is formed approximately equal to the diameter (d) of the circular section of the electrode. The long side end part thereof is beveled as shown by a symbol (r), to make the arc easy to oscillate. The weld line direction X-Y is made the short side of the rectangular section and the width thereof is set at (t). Next, alternating magnetic fields are applied from a magnetic controller 7 to the electrode 2 of this shape in the arrow 8 direction, thereby oscillating the arc in the arrow A-B direction. Since this welding method controls the arc smoothly by the slight change in the magnetic fields while maintaining the arc constant, the depth of penetration in both end parts of beads is positively assured. COPYRIGHT: (C)1982,JPO&Japio

Tubular composite arc welding electrode for vertical up welding of stainless steel

Abstract: In a tubular composite electrode for depositing stainless steel weld metal, satisfactory performance in vertical up welding is achieved through the inclusion in the electrode core of a slag mix comprising 15 to 60% weight percent zirconium dioxide.

Mig arc welding method

Abstract: This disclosure relates to MIG welding. In order to obtain an instantaneous short circuit type of metal transfer in the process using only a pure inert gas shield a small amount of rare earth elements is added to the weld wire. The amount of rare earth added is between 0.02%-0.03% by weight of the wire.

Liquid cooling for a welding torch

Abstract: During operation of a welding torch (10), electrode wire (17) travels through a contact tip assembly (14) directly into a weld area. The torch (10) is exposed to elevated temperatures which can cause damage from weld spatter and increased deterioration of the assembly (14). In the welding torch (10), a liquid is delivered onto an expansion element (44) and gasifies owing primarily to the elevated welding temperatures at the expansion element (44). The result is to cool the assembly (14) and substantially overcome the problems of temperature. In a nozzle (18) equipped torch (10), the nozzle (18) directs a portion of the gasified liquid to the welding area for shielding the welding operation.

Method of electric welding tinfree cans

Abstract: Disclosed are a method of and apparatus for making a welded metallic can body by effecting a mash resistance welding on a lapped side portion of a can body preform by means of a combination of a cooled elongated electrode and a cooled rotary electrode and, as required, with wire electrodes interposed between the lapped side portion and these electrodes. Also, disclosed are a tinfree steel welded can body and its making method wherein it is formed by a mash resistance welding on a lapped side portion of a can body preform made from tinfree steel, without requiring the removal of surface chromium film from the welded portion and its vicinity.

Arc welding method

Abstract: PURPOSE: To eliminate the melt sticking of base metals and a wire electrode and improve welding performance by stopping the feeding of the wire, thence breaking welding voltage and again applying the same and breaking it after a prescribed time, in stopping welding. CONSTITUTION: The output signal (a) of a main control device 1 is an L level while no welding is accomplished, and when it goes to an H level at the start of welding, a wire feed control device 2 is started; at the same time, a welding power source 10 is started by way of a welding voltage control circuit 7. Hence, a motor 3 is started, by which wire feed rollers 4 are revolved, and a wire 5 is fed to base metals 6; at the same time, welding voltage is applied to generate the arc 16, whereby welding is started. When the signal (a) goes to the L level, the device 2 is stopped immediately, and despite excessive projection of the wire 5 owing to the inertia of the feed mechanism including the motor 3, the electric source 10 is reapplied for a prescribed time after the prescribed time of the breaking of the power source 10 by the circuit 7, and therefore the arc 16 is refired to melt the excessively projecting wire 5, thereby eliminating the melt sticking thereof to the base metals 6. COPYRIGHT: (C)1982,JPO&Japio

Process for the submerged-arc welding of light metals such as aluminum and aluminum alloys

Abstract: A welding process for joining aluminum materials in a horizontal welding position, without preheating, this process being highly economical and characterized by minimal environmental pollution, good strength and toughness of the welded joint, in which process the arc, as in submerged arc welding of steel plates, is covered by a flux layer and burns in a closed cavity, this process being realized by the use of a flux having a flux composition of 20-70% potassium chloride (KCl), 20-70% of an alkaline earth metal chloride, preferably calcium chloride and/or magnesium chloride (CaCl 2 and/or MgCl 2 ), 1-20% of calcium fluoride (CaF 2 ) and preferably 1-15% of a substance capable of lowering the melting point and/or releasing gas.

Consumable electrode type arc welding method

Abstract: PURPOSE:To perform even welding by using the power source which combines the approximately constant current characteristics of small fluctuations in the output current voltage of the power source in a transient state and the approximately constant voltage characteristics and further change to approximately constant voltage characteristics of a short time until a steady state is reached in the neighborhood of the operating point in a steady state CONSTITUTION:A consumable electrode is fed at approximately a constant speed and a power source having the non-linear characteristics wherein the output voltage and current characteristics of the welding power source near the operating point change from approximately constant current characteristics to approximately constant current characteristics is used, so that the operating point in a steady state during welding is held let to exist on the approximately constant voltage characteristics and the operating point having moved depending upon the fluctuations in the arc length or arc voltage during welding is moved along the specified characteristic curves and is converged at the balance point For example, when the operating point moves to P51 upon changing of the arc length owing to disturbance, the operating point moves in the direction of PS-5 on the curve running the point P51 and moves downward on the curve PS-5 from the point P511 and converges at the operation point P50 of a steady state

Composite wire for stainless steel welding

Abstract: A composite wire containing a flux for use in gas-shielded arc welding of stainless steels which contains, in the flux, the following inorganic components with respect to the total weight of the wire: 0.1 to 10% by weight of an anhydrous silicate, and 0.01 to 0.75% of a metallic oxide having a melting point of no more than 888° C.

Gelatinous coating for arc welding and method for underwater welding

Abstract: A gelatinous coating comprising particles of electrode coating and thermite suspended in a gel for use as an insulating coating and fluxing agent in underwater arc welding. Also, a method for underwater welding in which the gelatinous coating is scorched and the electric arc is initiated and sustained so as to weld the workpiece. Alternatively, a method for arc welding in flammable or explosive atmospheres.

Slag-metal reactions during flux shielded arc welding

Abstract: SLAG-METAL REACTIONS DURING FLUX SHIELDED ARC WELDING

Torch for gas-shield arc welding in deep narrow groove

Abstract: A torch for gas-shielded arc welding in a deep narrow groove comprises a current contact torch bit (1) with an electrode (2) and a nozzle for supplying the shielding gas to the welding zone, which communicates with a gas-feeding tube (4) and is provided with at least one row of horizontally arranged holes (5). The nozzle is a closed chamber (3) made as a symmetrical wedge whose sharp edge faces the electrode (2) and is in one plane with the axis thereof. The side walls and bottom of the chamber (3) feature at least one additional row of holes (6) whose axes lie in one plane approximately perpendicular to the walls (7) of the groove. The torch is designed primarily for welding of very thick workpieces.

Method of manufacturing a monolithic metallic matrix coated with a catalysis promoting metal oxide

Abstract: The invention relates to a method for the manufacture of a metallic matrix which is "monolithic", is coated with a catalysis promoting metal oxide and is disposed in a metal casing, in which the matrix is composed of alternately disposed plain and corrugated or folded metal sheets or plates, in which these sheets are stacked in a pile or are wound into a spiral. The method comprises a special resistance welding on the end faces of the matrix and arc welding of the side face of the matrix to the side of the casing, on which the metal oxide is applied.

Arc welding process.

Abstract: An arc welding process for welding a circumferential surface of a fixed pipe etc. by shielding a work part with a shield gas is provided. It is welded by a flat arc formed in a flat sectional view by simultaneously ejecting a gas from nozzles (19) to the arc formed between a welding torch (10) and a product for welding by placing a pair of the gas nozzle (19) for ejecting the gas at the end of the welding torch (10).

Method for arc-welding the blades to the disc or counterdisc of rotary machine rotors

Abstract: For welding rotor blades to a rotor disc of a rotary machine, a welding process is used wherein grooves, called blind slots, are formed through the disc wall thickness but not to the extent to pass through the entire thickness, whereafter the blades are basted by a Tungsten Inert Gas run without added welded material, the blind slots being then filled up by a series of Tungsten Inert Gas welding passes but with added weld material. Headroom limitations are offset and the weld seams come out more robust and with a better surface quality.

Wire for low spatter carbon dioxide gas shielded arc welding

Abstract: PURPOSE:To reduce the amt. of spatters by contg. C, Mn, Si at specific %, contg. one or more kinds of Se, Te and Sb at specific % in total and keeping Ti and Al at specific %. CONSTITUTION:Spatters owing to gaseous explosion, releasing of air bubbles, etc. are reduced by limiting <=0.06% (wt%, herinafter the same) C. The wire is contained with 1.3-1.9% Mn and 0.8-1.2% Si respectively, contains 0.005-0.2% one or more kinds of Se, Te, and Sb in total, and consists of the balance Fe and unavoidable impurities. Both Ti and Al are kept at <=0.05%, whereby the wire for low spatter CO2 gas shielded arc welding is obtained.

Arc welding equipment

Abstract: PURPOSE:To achieve the stabilization of a crater part by setting the 1st welding conditions during welding at the constant welding current conditions in which no pulses are included and the 2nd welding conditions at the end of welding at the welding current conditions in which the combined pulses of a pulse current supply source and a constant speed wire feed speed are included. CONSTITUTION:The output end of a current supply source 1 is connected in parallel with a pulse current supply source 2 through contacts 12, 13, and current is supplied from the connection point of the contacts 12, 13 to an electrode wire 4 through a power feed tip 6. On ther other hand, the electrode wire 4 is fed to the direction of base metals 5 by the driving roller 8 mounted to the shaft of a motor 7 which is driven by a wire feed circuit 3, thereby connecting the arc 9. Here, during regular welding, the contacts 12, 14 are closed and welding is performed by the combination of the speeds set by the current supply source 1 and a wire speed regulator 10. The contacts 12, 14 are opened and the contacts 13, 15 are closed by the crater signal on the verge of the welding end and small current pulse welding is performed by the combination of the speeds set by the pulse current supply source 2 and a wire speed regulator 11.

Apparatus for gas-shielded arc welding

Abstract: An apparatus for gas-shielded arc welding comprises a mechanism (1) for guiding and feeding an electrode to a welding zone (3), a nozzle (4) for feeding a protective gas medium to the welding zone (3) and a TV transmission camera (6) for realtime monitoring of the welding process. A cover plate (8) made of an optically transparent material is provided at the end (7) of the gas nozzle (4) which is remote from the welding zone (3), and a lens (9) of the TV camera (6) is installed above the cover plate (8) coaxially therewith. The distance ("a") from the cover plate (8) to the lens (9) is selected in such a manner that the zone (3) of sharpness of the lens is located beyond the edge (11) of the gas nozzle (4) which is adjacent to the welding zone (10) and extends over the components of the welding process. An apparatus for gas-shielded arc welding is designed preferably for welding thick plate materials, for example, pressure vessel casings.

Electron-beam welding

Abstract: An electron-beam welding system for use in welding large masses of magnetic metals such as steel. Abutting segments of metal masses such as adjacent plates are welded by electron-beam welding. Two electron-beam welding units are used. One unit is used from one side of the plates to preheat the joint to a temperature to the transformation melting temperature. This preheating eliminates the magnetic field in the heating area. Subsequent electron-beam welding from the other side of the plates, while still hot, creates a welded joint in which the electron-beams are unaffected by magnetic fields within the plates.