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Showing papers on "Shielded metal arc welding published in 1985"


Patent
18 Dec 1985
TL;DR: In this paper, the welding method is used to lay down weld beads on metallic substrates with a narrow width of 0.125 inch and less, and the powdered metal which is delivered is laid down in a series of overlapping weld deposits which solidify very rapidly and produce a fine grain structure.
Abstract: The welding method may be used to lay down weld beads on metallic substrates with a narrow width of 0.125 inch and less. The process employs a plasma transferred arc and pulses the current delivered to the arc such that a wave form having at least a main amplitude and a lower auxiliary amplitude is provided. The powdered metal which is delivered is laid down in a series of overlapping weld deposits which solidify very rapidly and produce a fine grain structure.

42 citations


Patent
04 Jul 1985
TL;DR: The gas metal arc welding process of the present invention extends the axial spray metal transfer range with a non rotating arc from 10 to 25 Ibs/hr using an electrode wire diameter between.035 to.052 inches as discussed by the authors.
Abstract: The gas metal arc welding process of the present invention extends the axial spray metal transfer range with a non rotating arc from 10 to 25 Ibs/hr using an electrode wire diameter between .035 to .052 inches. The process is carried out by maintaining an electrode extension of between 3/4 to 1 1/4 inches with a three component shielding gas mixture consisting essentially of argon and oxygen in combination with carbon dioxide or carbon monoxide in a volume proportion of oxygen 1-2%, carbon dioxide 8-15%, balance argon. The arc voltage is maintained in a range of between 29 and 40 volts.

17 citations


Journal ArticleDOI
TL;DR: In this article, the kinetics of hydrogen attack on base metals and the weld metals of two Q&T 2.25 Cr-1 Mo steel weldments made by different techniques were studied in the temperature range 460 to 590°C (860 to 1094 °F) and 10 to 23 MPa of hydrogen.
Abstract: The kinetics of Hydrogen Attack (HA) of the base metals and the weld metals of two Q&T 2.25 Cr-1 Mo steel weldments made by different techniques (SMAW and SAW) were studied in the temperature range 460 to 590°C (860 to 1094 °F) and 10 to 23 MPa of hydrogen. A sensitive dilatometer used to measure the rate of HA showed that the weld metals suffered HA at significantly higher rates than the base metals. The SMAW weld metal was inferior to the SAW weld metal and swelled nearly an order of magnitude faster than the base metal. This behavior is due to a significantly higher bubble density, and a resulting higher contribution of power law creep of the matrix. The SAW behavior was intermediate between those of the base metals and the SMAW. For the same hydrogen pressure the operating limit of the SMAW weld would be roughly 100°C lower than that of the base metals, and that of the SAW roughly 50°C lower.

15 citations


Patent
26 Mar 1985
TL;DR: A method for improving the weld strength, structure and crevice corrosion resistance of nitrogen-containing alloy weldments by adding nitrogen to the inert gas used for shielding during the welding operation is described in this article.
Abstract: A method for improving the weld strength, structure and crevice corrosion resistance of nitrogen-containing alloy weldments by adding nitrogen to the inert gas used for shielding during the welding operation.

15 citations


Patent
05 Dec 1985
TL;DR: In this article, the welding rod is introduced into the torch in such a way that it is located in the arc between the end of the non-consumable electrode and the workpiece and accordingly passes in an electroless dripping manner into the arc.
Abstract: The invention starts from the known WIG or plasma welding process using an inert gas, with weld (filler) material being supplied as a welding rod (wire). According to the invention, the welding rod is introduced into the torch in such a way that it is located in the arc between the end of the non-consumable electrode and the workpiece and accordingly passes in an electroless dripping manner into the arc. Accordingly, the torch is equipped with a welding rod feed, by means of which the rod can be introduced into the nozzle channel of the torch and accordingly into the arc.

14 citations


Journal ArticleDOI
TL;DR: In this article, the exposure of welders in Dutch industries to total particulate, chromium, nickel and copper fume during the welding of unalloyed, stainless and high alloyed steels has been investigated.
Abstract: The exposure of welders in Dutch industries to total particulate, chromium, nickel and copper fume during the welding of unalloyed, stainless and high alloyed steels has been investigated. The exposure to the gases NO2, NO and ozone is also discussed. The results are presented in tables and graphs. The correlation between the arc-time factor and the welding fume concentration in the breathing zone appeared to be bad MMA-welding fumes of stainless steel contain mainly soluble hexavalent chromium. During MIG and TIG welding the fumes contain chromium which was insoluble in water and not hexavalent. The nickel was insoluble in water in all three processes. In comparison with the Dutch occupational health standards, it appears that the dust exposure is often higher than the limit value of 5 mg m3 in M MA and gas-shielded arc welding. The exposure to chromium is usually higher than the standard of 0.05 mg m 3 lor hexavalent chromium and the standard o[0.5 mg m-3 lor total chromium in MMA welding of stainless steel, and the exposure to copper fumes during welding of copper is usually higher than the standard of 02 mg m3. Among the gaseous contaminants NO2, NO and ozone, only ozone with MIG welding of aluminum gives concentrations in the breathing-zone exceeding the standat'd of 0.2 mg m3(0.1 ppm).

13 citations


Patent
05 Aug 1985
TL;DR: In this article, metal filler compositions based on manganese and nickel for the welding of cast iron are disclosed, which are particularly useful for welding gray and ductile (nodular) cast irons.
Abstract: Metal filler compositions based on manganese and nickel for the welding of cast iron are disclosed. The filler composition preferably contains about 15 to 50% manganese and 15 to 35% nickel. The filler compositions may be incorporated into a welding rod for Shielded Metal Arc (SMA) or into the welding wire for Gas Metal Arc (GMA) welding or added as metal powders in Flux Cored Arc (FCA) or submerged Arc (SA) welding. The compositions are particularly useful for welding gray and ductile (nodular) cast irons.

9 citations


01 Jun 1985
TL;DR: In this article, small additions of sulfur dioxide (SO/sub 2/) to the torch shielding gas when welding two stainless steels were shown to improve GTA weld depth/width ratio.
Abstract: Substantial increases in GTA weld depth/width ratio resulted from small additions of sulfur dioxide (SO/sub 2/) to the torch shielding gas when welding two stainless steels. The improvement was demonstrated on both Types 304 and 21-6-9 austenitic stainless steels, but would be expected for iron-base alloys generally. The weld pool shape achieved was essentially independent of variations in both SO/sub 2/ content of the torch gas and base metal composition when SO/sub 2/ in the shielding gas was in the range of 500 to 1400 ppm. With 700 ppm SO/sub 2/ in the torch gas, less than 30 ppm sulfur was added to an autogenous weld bead. For alloys where this additional sulfur can be tolerated and appropriate measures can be taken to handle the toxic SO/sub 2/, this technique offers a promising way to improve GTA weld joint penetration while suppressing variable penetration.

9 citations


Patent
15 Oct 1985
TL;DR: In this article, a weld metal for welding of a titanium alloy member to a ferrous based alloy member as an intermediate transition zone between such members so as to overcome the metallurgical imcompatability of each such member, which consists of a vanadium metal, titanium and iron and inconsequential amounts of brittle intermetallic compounds.
Abstract: The invention is a weld metal for welding of a titanium alloy member to a ferrous based alloy member as an intermediate transition zone between such members so as to overcome the metallurgical imcompatability of each such member, and which consists of a vanadium metal, titanium and iron and inconsequential amounts of brittle intermetallic compounds. The preferred weld metal is vanadium rich and contains no more than 50% combined weight of titanium and such a weld metal is produced in accordance with our invention by fusion welding, particularly capacitor discharge welding, which because of its inherent but heretofore unrecognized extremely fast quench or freeze rates will produce a fusion weld between these two metallurgically incompatible alloys which is free of brittle intermetallic compounds. It is also part of our invention that such a weld metal of the aforesaid composition will have independent use as a welding alloy, particularly when fabricated in sheet form.

8 citations


Journal ArticleDOI
TL;DR: In this article, the effects of welding conditions and the nitrogen partial pressure on the nitrogen content of stainless steel weld metal were systematically studied. 20Cr-10Ni stainless steel was welded in N2 and N2-Ar atmospheres at 1-30 atm pressures.
Abstract: 20Cr-10Ni stainless steel was welded in N2 and N2-Ar atmospheres at 1-30 atm pressures. Effects of welding conditions and the nitrogen partial pressure on the nitrogen content of stainless steel weld metal were systematically studied. The results are summarized as follows:(1) In the nitrogen welding atmosphere, the nitrogen content of the weld metal decreased with increasing the welding current and increasing the travel speed, and with decreasing the arc voltage.(2) In the nitrogen welding atmosphere, the nitrogen content of the weld metal increased with the nitrogen pressure, but the nitrogen absorption of the weld metal does not obey the Sieverts' law.(3) In N2-Ar welding atmosphere, the nitrogen content of the weld metal was lower in high atmospheric pressure than in low pressure at the same nitrogen partial pressure.(4) Using thermodynamic data obtained by equilibrium study, the nitrogen absorption into the stainless steel weld metal in the nitrogen atmosphere of high pressure was discussed.(5) All stainless steel weld metals had no porosity.

6 citations


Patent
20 May 1985
TL;DR: In this paper, an arc welding control system is described, where the welding current is held to a very low value during the time a welding electrode is coupled with a workpiece.
Abstract: An arc welding control system wherein the welding current is held to a very low value during the time a welding electrode is coupled with a workpiece. When the welding electrode is disengaged from the workpiece, a very low current pilot arc is established. Then, arc voltage monitors effect, first, an increase in the current of the pilot arc and then the closing of a welding current contactor. Both shielded metal arc welding and gas tungsten arc welding modes are accommodated; and, in the latter, when a too low arc voltage condition is detected, arc voltage monitors effect the opening of the welding current contactor for such time as the too low arc voltage condition exists. While the welding current contactor is open, a low current pilot arc is maintained until the too low arc voltage condition is corrected.


01 Jan 1985
TL;DR: In this article, the authors describe physical, chemical and biological studies of fumes from six types of flux-coated welding rods, and a companion study of the bacterial mutagenicity of 24 metal salts.
Abstract: vl This thesis describes physical, chemical and biological studies of fumes from six types of flux-coated welding rods, and a companion study of the bacterial mutagenicity of 24 metal salts. The choice of the welding rods was based on market availability and use, and chemical considerations. Fume was generated using an automatic arc welder (MMAW process). The mutagenicity study focussed on nickel (II) and chromium (VI), putative carcinogens present in certain welding fumes. Summaries of individual fume and mutagenicity studies are given below: (1) The generation rate and chemical composition of fume from AC welding of E316L-16 stainless steel electrodes were studied under a wide range of current (80120A) and voltage (20-40V) conditions. The marked variations observed in the fume generation rates and fume composition are discussed In terms of arc temperature, gas shielding effects and the volatility and thermodynamic stability of fume components. (2) Fume from E316L-16 stainless steel electrodes was examined by x-ray photoelectron spectroscopy. Fourteen elements were determined. Necessary chemical information on the fume was obtained using various analytical techniques. It is demonstrated that NaF and KF are preferentially enriched on the particle surfaces and that Na, K, F and CrtVI) are appreciably leachable by water. The toxicological significance of the results is discussed.

01 Aug 1985
TL;DR: In this article, the fracture-toughness of Austenitic stainless steels is analyzed for three different welding processes: gas tungsten arc (GTAW), shielded metal arcmore (SMAW), and flux cored arc (FCAW).
Abstract: The magnets that will provide containment of the intensely hot plasma in fusion reactors must be wound with superconductors to enable these reactors to produce more energy than they consume (Ref. 1). With current superconductor technology, this requires the use of liquid helium at its boiling point (about 4 K, or -269/sup 0/C) as a coolant. At this temperature, all other known materials are solid. Austenitic stainless steels are the most widely used alloys for structural applications below 77 K (-196/sup 0/C) (Ref. 2). Their physical properties offer advantages over those of competing materials; the elastic modulus is high, and the thermal expansion, magnetic permeability, and electrical and thermal conductivities are low. Their mechanical properties, including strength, ductility and fracture toughness, are generally adequate to withstand the large forces imposed on magnet structures reliably. A possible exception to this statement arises in the case of weldments; the limited 4 K (-269/sup 0/C) fracture toughness data for austenitic stainless steel weld metal show a wide range of values, with no obvious explanation for the large differences. This report summarizes the data available in the literature, contributes new data for three different welding processes - gas tungsten arc (GTAW), shielded metal arcmore » (SMAW) and flux cored arc (FCAW) - and offers some observations of the fracture morphology.« less

Patent
18 Oct 1985
TL;DR: In this paper, a flux for the submerged arc welding of aluminum-bronze comprises a granular mixture of cryolite and a binder; the flux preferably also contains alumina.
Abstract: A flux for the submerged arc welding of aluminum-bronze comprises a granular mixture of cryolite and a binder. The flux preferably also contains alumina. A method for the submerged arc welding of aluminum-bronze employing the flux is disclosed.

Patent
06 Jul 1985
TL;DR: In this article, the bottom surface of a plug is machined into a prescribed bottom-surface shape, and a hard facing is provided to the underlayed contacting surface by a shielded metal arc welding by using a welding rod of Fe-Cr alloy.
Abstract: PURPOSE:To improve remarkably bottom-surface wearing of a plug by providing a hard facing with the use of a wear-resisting metal to the mandrel bar contacting part of the bottom surface of a plug of reeling mill. CONSTITUTION:The contacting surface of the bottom surface of a plug 24, consisting of FC30 (JIS) for instance, in which a wear of bottom surface is already produced by a mandrel bar is provided with an underlaying 30 by a shielded metal arc welding of single layer by using a welding rod of Fe-Ni alloy. Next, a hard facing 32 is provided to the underlayed contacting surface by a shielded metal arc welding by using a welding rod of Fe-Cr alloy. Further, the surface is machined into a prescribed bottom-surface shape.

01 Aug 1985
TL;DR: In this paper, the ASME Boiler and Pressure Vessel Code (WPS-1101) was used for gas tungsten arc welding of copper alloys in thickness range 0.125 to 1.0 in.
Abstract: procedure WPS-1101 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc welding of copper alloys C10200, C10400, C10500, C10700, C12000, C12200 and C12300 (P-31), in thickness range 0.125 to 1.0 in.; filler metal is ERCu. (F-31); shielding gas is helium.

01 Mar 1985
TL;DR: In this paper, the authors describe the program of explosion bulge testing of 50 mm thick Australian sourced HY-80 steel plate, supplied by Bunge Industrial Steels P/L to Industry Development Branch (NSW Region) to specification MIL-S-16216H (SHIPS).
Abstract: : This report describes the program of explosion bulge testing of 50 mm thick Australian sourced HY-80 steel plate, supplied by Bunge Industrial Steels P/L to Industry Development Branch (NSW Region) to specification MIL-S-16216H (SHIPS). The testing was undertaken as part of the qualification of this steel in compliance with U.S. NAVSEA requirements. The report deals with the first series of tests which were unsuccessful, the testing of unwelded plate, the development of manual metal arc welding procedures and the investigation of candidate welding consumables which ultimately led to a successful test series. The successful welds used low hydrogen electrodes of teh AWS 10018 M type supplied by Philips (UK). The procedure followed a stringer-bead technique with strict limits on heat input, and a weld design incorporating a novel top-hat profile aimed at locating the weld toes (potential crack initiation sites, well away from the remaining weld fusion boundary (potential path for through-thickness crack propagation). (Author)

Patent
28 Mar 1985
TL;DR: In this paper, a method of butt welding of flat steel plate or steel pipe seams by a submerged arc process is described, in which weld metal is deposited in the weld gap from one side only including the steps of applying powdered flux (21) and compacting the flux by a support device (10) and a conveyor (12).
Abstract: There is disclosed a method of butt welding of flat steel plate or steel pipe seams by a submerged arc process in which weld metal is deposited in the weld gap from one side only including the steps of applying powdered flux (21) to the weld gap, compacting the flux by a support device (10) and a conveyor (12) and maintaining the flux in position whilst weld material is applied to the weld gap.

01 Aug 1985
TL;DR: Procedure WPS-2651-ASME-1 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc welding of carbon steel (P1-1) to nickel-chromium-iron (P-43), in thickness range 0.125 to 0.432 in; filler metal is ERNiCr-3 (F-43); shielding gas is argon.
Abstract: Procedure WPS-2651-ASME-1 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc welding of carbon steel (P-1-1) to nickel-chromium-iron (P-43), in thickness range 0.125 to 0.432 in.; filler metal is ERNiCr-3 (F-43); shielding gas is argon.

Patent
14 Mar 1985
TL;DR: In this article, an apparatus for electroslag welding and build-up welding contains a main welding head and an additional welding head, with the main head having a device for moving a nozzle and a consumable wire electrode.
Abstract: The apparatus for electroslag welding and build-up welding contains a main welding head (1) and an additional welding head (15), the main welding head (1) having a device (3) for moving a nozzle (4) having a non-consumable electrode (5) and a consumable wire electrode (6) as well as a device (7) for feeding the consumable wire electrode (6) into the slag pool, while the additional welding head (15) has a device (16) for feeding a consumable rod electrode (17) and a filler wire (18) into the slag pool. The additional welding head (15) is arranged on the main welding head (1) with the means of changing the angle of inclination of the consumable rod electrode (17) relative to the non-consumable electrode (5).

Patent
05 Dec 1985
TL;DR: In order to improve the firing properties occurring in particular in inert gas shielded arc welding with a welding wire, the wire beads which are formed at the end of a welding process at the free end of the electrode are loosened by means of a final current pulse as mentioned in this paper.
Abstract: In order to improve the firing properties occurring in particular in inert gas shielded arc welding with a welding wire (12), the wire beads (17) which are formed at the end of a welding process at the free end (16) of the electrode are loosened by means of a final current pulse.

Journal ArticleDOI
TL;DR: In this article, the microstructure in both the heat-affected zone (HAZ) and the weld metal of both welds has been characterized by optical, scanning, and transmission electron microscopy in conjunction with microhardness traverses.
Abstract: A systematic microstructural characterization in the heat-affected zone (HAZ) of two ASTM A710 grade A steel weldments (one preheated and the other pre–cooled), employing identical shielded metal arc welding conditions, has been performed. The microstructure in both the HAZ and the weld metal of both welds has been characterized by optical, scanning, and transmission electron microscopy in conjunction with microhardness traverses. No difference in microstructure was observed in the HAZ on comparing the preheated and non-preheated weldments. The only significant difference observed in the two weldments was the width of the HAZ, which is about 1 mm wider for a preheated weldment. Examination by transmission electron microscopy revealed the following microconstituents in the HAZ of both the weldments: polygonal ferrite, acicular ferrite, ferrite–carbide aggregates, e-copper and fine cementite precipitates, martensite, tempered martensite, retained austenite, and transformation-twinned martensite. The...

Patent
10 Jan 1985
TL;DR: In this article, a simple method was proposed to oscillate a welding arc by ejecting alternately a shielding gas and a control gas having a different potential inclination from the right and left with respect to the advancing direction of a welding torch.
Abstract: PURPOSE:To oscillate a welding arc by a simple method in the stage of gas shielded metal arc welding by ejecting alternately a shielding gas and a control gas having a different potential inclination from the right and left with respect to the advancing direction of a welding torch. CONSTITUTION:A voltage is impressed between a welding wire 1 attached to a welding torch 1 and materials 21 to be welded to generate an arc 20 and to melt the wire 1, thereby welding the groove of the materials 21. A shielding gas 23 such as Ar is ejected from the gas nozzle 2 on the outside of the torch 1 to shield the weld zone against air. Gaseous CO2 24 are ejected alternately from the left and right side as a control gas in the stage of such welding. Since the gaseous CO2 has the ionization potential higher than the ionization potential of the gaseous Ar, the arc 22 is swung alternately to the right and left side walls 21a, 21b of the groove toward the direction where the potential inclination is low and therefore the groove is welded with weaving without oscillation of the torch 1.

Patent
24 Aug 1985
TL;DR: In this article, a control gas (Gaseous carbon dioxide) is ejected from holes 1a, 1b punched on both sides at the bottom end of a welding torch 1 in this state to oscillate the arc 5 to the right and left around the wire 3.
Abstract: PURPOSE:To control easily and economically a torch so as to profile exactly a groove line by ejecting alternately a control gas having the potential inclination different from the potential inclination of a shielding gas from both right and left sides of a welding torch and controlling the movement of the welding torch in the transverse direction of the groove so that the right and left arc lengths are made equal. CONSTITUTION:A shielding gas (Ar, etc.) is ejected around the arc 5 generated between the top end of a welding wire 3 and materials 4 to be welded from a nozzle 6 to shut off air. A control gas (gaseous carbon dioxide) 8 is alternately ejected for specified time from holes 1a, 1b punched on both sides at the bottom end of a welding torch 1 in this state to oscillate the arc 5 to the right and left around the wire 3. The arc voltage when the arc 5 is oscillated to the right side wall 4b and left side wall 4a of the groove is detected and the torch 1 is moved in the transverse direction of the groove so that the arc lengths lR, lL are made equal. The torch 1 is thus moved to profile the weld line.

Patent
13 Jun 1985
TL;DR: In this article, the authors propose to turn an arc by a simple mechanism by jetting not only a shielding gas but also a control gas whose potential inclination is different from the shielding gas, in the vicinity of the arc successively from at least three directions of the circumference of a welding torch.
Abstract: PURPOSE:To turn economically an arc by a simple mechanism by jetting not only a shielding gas but also a control gas whose potential inclination is different from the shielding gas, in the vicinity of the arc successively from at least three directions of the circumference of a welding torch CONSTITUTION:A welding wire 20 is fed into a wire hole of a wire supply body 2, straightened through a hole of a contact chip, and an arc 22 is generated by applying an electric power source On the other hand, a shielding gas 23 of Ar, CO2, etc and a control gas whose potential inclination is different from said gas are jetted to the vicinity of the arc 22 successively from holes 1a, 1b and 1c provided on the circumference of a welding torch 1, and the arc 22 is turned