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Welding_arcinexpensive or modern equipmentSOLUTIONS with Effective, Powerful Advice
What is in here for me? How can one get information on Welding_arc equipment? Is it worth to switch from one type of Welding_arc equipment to another? What are the specific advantages and limitation of any one equipment? Some information is provided here, but answers are generally complex. One needs to take into account specific requirements and constraints. Therefore it is not practical to propose a general plan giving one solution for every need. The more is known about the specific situations and the possible solutions, the easier it is to reach acceptable conclusions. However it is always possible to look for a second opinion. Please ask, by clicking on the Contact Us button above left to e-mail us. When procuring new hardware, as needed to perform any given welding process, one should be aware of all available options. In a previous page on WELDING EQUIPMENT, a short review was offered of the main concerns. Here we are going to enter into some more details on Welding_arc equipment used for ARC WELDING.
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For more information on these Arc Welding Processes you may click on the underlined subject title. Of the Fusion Welding Processes, Welding_arc in general is characterized by the use of the electric arc as the source of heat for melting and fusing materials. Some form of protection of the molten pool and of the hot metal must be adopted against contamination from air, by one of a series of means, each best adapted to some specific application. See our page on Power Sources.
Now for SMAW...
The shielded metal arc welding (SMAW) process, makes use of an electrical circuit that helps to start and maintain a welding arc, that converts energy into heat. Is is is essentially a manual process (also called Stick Welding). The heat from the welding arc is localized, intense and concentrated. It melts the electrode tip, the electrode cover and also part of the workpiece near to it. The welder's skill maintains the required gap, between the electrode and the workpiece, and directs the weld pool to fill the joint with molten metal. The consumable electrodes have a coverage with materials that promote the arc. While burning, the coverage develops a shielding envelope of protective gases. It leaves on the molten metal a floating cover of slag-forming materials that protect from air the hot metal. After cooling down, the remaining slag covering the weld must be removed by lightly hammering and brushing. The main piece of Welding_arc equipment for this process is a power supply. Different types are offered on the market, each rated to a maximum output in Amperes. The nominal rating is limited by some approved duty cycle, which is a given percentage of working time. It is calculated for any ten minutes interval, at any given current, and intended to avoid dangerous equipment overheating. A new page can be reached by clicking on Shielded Metal Arc Welding Tips. A detailed Article on how to select your SMA Welder or GTA Welder was published in the September 2003 issue #01 of Practical Welding Letter. To reach it, click on PWL#001. To get all the issues of PWL as they are published, please Subscribe. Transformers. The basic power supply for alternating current (AC) Welding_arc is a simple step down transformer. It is designed with almost constant current (and drooping voltage), giving high current, even when the low, safe voltage changes somehow with the arc length. The arc length is controlled by the welder's manipulation of the electrode holder. The cables connect the electric output to the electrode holder (in a regular SMAW outfit) and to the work. The polarity is alternating with the frequency of the mains grid (50 or 60 Hz). The arc is maintained even when the current is momentarily zero (twice in a complete cycle). Welding_arc small units are available, even for Hobby and Home Welding or farm applications, usually with low initial cost. Their main drawback is a poor power factor which causes unbalanced load on the mains grid and may be penalized by the Electric Company. Transformers may not be suitable for welding thin parts with very low currents. If AC output only is what you need and if you wish to consider a portable Welding_arc welder for do-it-yourself home and hobby work you can find what fits you. Welding gloves and personal protection accessories are needed even for the simplest welds. While generating and maintaining an arc for welding purposes is not unduly difficult, an initial welding course is always recommended for everybody, especially for learning Safety issues.
Generators For welding far away from an electrical mains line, special power supplies are used. Generators or alternators provide the required electrical supply needed for welding. The mechanical energy to be converted is obtained from a prime motor, usually an internal combustion engine. Click on: Welding Generators
Depending on requirements, suitable Welding_arc welders could be considered. Hobart Stickmate 205 AC Stick (SMAW) Arc Welding Power Source #500502 It is rated for welding 3/8" thickness in steel. A Brochure for STICKMATE® 205 AC is downloadable from For a complete description see the Owner's Guide downloadable from Alternating current (AC) permits using longer cables with less current loss (as heat), as compared to direct current (DC) Welding_arc power supplies. Electrodes must be specially formulated for ac/dc use and produces a somewhat less stable arc and more spatter than when using DC. AC reduces the problem of Arc Blow that may occur because of magnetic field interference. DC Power Supplies. Welding_arc direct current (DC) power supplies are of different types, rectifier, motor-generator or inverter. Usually they provide constant current (and drooping voltage), and are used for SMAW, GTAW, SAW and Plasma. A switch is often provided which permits selection of electrode negative (straight polarity) or electrode positive (reverse polarity) without having to disconnect and reconnect the cables. For operation in the field, far from line power supply, engine-driven generators are available.
Combination ac/dc Welding_arc power supplies are available, providing all the versatility needed, at some extra cost. Sometimes direct current power supplies are equipped with superposed high frequency pilot spark, to ease and to stabilize arc striking. HF however can interfere, by radio disturbance, with sensitive equipment nearby. If you cannot renounce the DC option you could consider the following: Hobart Stickmate AC/DC Welder - LX235 230 Volt, 235 Amp, Model# 500421 For more data see the short Data Guide available from A Brochure for STICKMATE® LX 235 AC/160 DC is downloadable from For a complete description see the Owner's Guide downloadable from Cables and electrode holder complete the equipment needed for Welding_arc SMAW. The welder needs individual protection gear as shown under SAFETY. Inverters. A different type of power supply, relatively recent, makes use of Welding_arc inverter technology. The electric power drawn from the grid is manipulated electronically: it is first rectified, then pulsed to high frequency, transformed to low voltage, and finally smoothed and supplied to the welding circuit. Using clever circuits, inverters make possible the supply of either AC or DC in a single low weight, small unit, much more portable than older outfits. The manufacturers claim economy of use (annual power savings equal to 10% the cost of power supply) and better efficiency than older units. The Welding_arc is more stable and high frequency stabilization is not needed, except possibly at start. Power supplies of this type can be used for all arc processes, when the necessary accessories are provided. One of the interesting benefits provided by inverters, for GTAW (Tig welding) of aluminum, is the capability to adjust the percentage of time with Electrode Negative (EN) vs. time with Electrode Positive. One recalls that EN provides better penetration while EP provides more cleaning action. This versatility in the hands of skilled welders is one more tool for performing Welding_arc of higher quality. You may wish to check power sources based on Inverter Technology. A detailed Article on Inverters, with more information and practical advice,
was published in the January 2004 issue #05 of Practical Welding Letter. Click on PWL#05 for reading. A new page on Stud Welding is visible by clicking on Stud Welding. You can subscribe at no cost to our periodic publication by clicking on Subscription. Note: the processes described hereafter, namely SAW, GMAW, FCAW, while quite different, have a common feature. Their consumables are supplied to the arc in the form of a continuous wire or strip. For this kind of processes the influence of a unique parameter must be understood. The electrode extension (also called electrode stick-out or length) becomes an important variable to be considered. It influences the arc current. The complete explanation is exposed for all processes in the following page.
Submerged under what?... SUBMERGED ARC (SAW) Welding_arc equipment includes a suitable power supply, generally capable of carrying elevate currents, and a motor driven, bare metal electrode feeder, supplying continuous wire. Included are means for the relative movement of workpiece and welding head, provisions for supplying the granulated flux (under which the arc is submerged, not visible to the operator) and of collecting its non fused fraction for reuse. Controls include current, usually dependent on wire feed speed, voltage, and translation speed. The granulated flux prevents radiation, sparks, fumes and spatter from being released, while assuring arc stability and the required properties. With multiple heads the process is amenable to tandem outfits, using both AC and/or DC supplies. Besides the high quality obtainable, the main advantage of using this Welding_arc equipment is the productivity gain. This is due to high weld metal deposition rate, for relatively long and thick joints, as compared to other less favorable processes. It can be used for surfacing with wire or strip, in the flat position. Power supplies include the types described above for SMAW, but they are generally specially designed for the process, with all the controls conveniently placed for the operator. In particular they are designed for continuous (100%) duty cycle except if otherwise dictated by the manufacturer. The arc heat melts some of the flux, the electrode and the workpiece edges. A thick slag cover, buried under the granulated flux, is generated which floats upon the molten metal. After cooling down, the solidified slag has to be removed by suitable means. Power sources can be Direct Current constant voltage, which are self regulating. With a (selectable) constant speed wire feeder, once the arc length is established by voltage adjustment, any arc length change caused by varying welding conditions, is automatically compensated by current increase or decrease, until the original arc length is reestablished. These power supplies are limited in maximum current, as arc blow may become too severe to be acceptable. Direct current constant current power supplies are not self regulating. Therefore they need a voltage sensing variable wire feed speed control in charge of maintaining the arc length. This type of control tends to be more complex and expensive than the one described above. See Submerged Arc Welding Tips. A detailed Article on how to select your Submerged Arc Welder was published in the December 2003 issue #04 of Practical Welding Letter. To reach it, click on PWL#04. An Article on Filler metals for Submerged Arc Welding was published in Section 4 in Issue 29 of Practical Welding Letter for January 2006. To read the article click on PWL#029. An Article on Submerged Arc Welding Optimization was published on The Fabricator. Click to see it. An Article on Submerged Arc Welding (SAW) on Cr-Mo-Ni steels was published (11) in Issue 104 of Practical Welding Letter for April 2012. To get all the issues of PWL as they are published, please Subscribe. Here is a new one... FLUX CORED ARC WELDING (FCAW) equipment (OK, not so new...) mostly uses Welding_arc direct current reverse polarity (Electrode Positive) power supplies. The constant current type works with a voltage controlled wire feed system that adjusts the feed to ensure constant arc length. In the constant voltage type, the filler wire is fed at constant speed, drawing the current needed to maintain the preset arc voltage. When wire feed is increased, the welding current grows accordingly. The hollow wire is full of a flux whose combustion products protect the molten material. Slag remaining on the weld bead must be removed manually as it is for SMAW (stick welding). The fumes are quite thick and not suitable for welding indoor unless a fume extraction system is operating. For outside welding the fumes of FCAW are considered more protective to the work than shielding gases that can be displaced by air drafts. Electrode holders can be used for semiautomatic or for automatic welding. They may or may not accommodate auxiliary gas shielding, usually carbon dioxide (CO2) or mixtures with argon (for steel), the selection being dictated by the application. Some holders are water cooled for use at high currents. Holders also provide sliding electrical contact to the flux cored wire. Wire feed systems, usually separate from Welding_arc electrode holder, pull wire from a reel and push it at constant speed by means of motor driven friction or knurled rolls through a guide to the holder. See a new page on Flux Cored Arc Welding Tips. Well known in the group... GAS METAL ARC WELDING (GMAW) also known as Mig, for Metal Inert Gas Welding_arc equipment is similar to the above except that filler metal wire is solid and bare, and that a protective gas is always used. It is possible that some of the applications overlap, and that the selection depends on the most practical and economic solution. The protective gas is usually argon for welding aluminum, magnesium and stainless steels, helium for highly conductive materials or for thick sections, and carbon dioxide (CO2) or gas mixtures (argon and 10-20% carbon dioxide) for carbon and low alloy steels. Both method presented above can be provided sometimes by the same equipment. If you need GMAW (Mig) - with shielding Gas (Argon for Aluminum or mixtures: Argon + 2%O2 for stainless, Argon + 10-20% CO2 for Mild Steel) and/or FCAW (Flux cored) - with or without Gas, then the following Welding_arc equipment is recommended. This one has a nominal maximum of 130 Amp operating from single phase 110V. Duty Cycle is 20% at 130 A.
Clarke 130EN Wirefeed Welder - 110 Volts, 130 Amps, Model# WE6523 See the following Welding_arc Equipment from another Manufacturer.
Hobart Handler 140 115-Volt 25-to-140 Amp Gas/Metal/Arc Single-Phase Wire Welding Package #500500 Input 115 VAC 1 phase Constant voltage DC Welds 24 gauge up to 1/4 inch Hobart Welding Spool Gun for IronMan 210 Mig Welder, Model# 195016 Includes spool gun and 20ft. cable. No module required for hookup to IronMan welders. See details in above Brochure for IronMan 210. For a complete description see the Owner's Guide downloadable from
See a new page on Mig Welding Tips. A detailed Article on how to select your GMA Welder and FCA Welder was published in the October 2003 issue #02 of Practical Welding Letter. To reach it, just click on PWL No. 02. An Article on Selection of GMAW Parameters for Short Circuit Mode was published in the Issue 23 of Practical Welding Letter for July 2005. Click on PWL No. 23 to read it. An Article on Selection of GMAW Parameters for Spray Transfer mode was published in the Issue No.24 of Practical Welding Letter for August 2005. To read it click on PWL No. 24. An Article on how to select GMAW Parameters for Robotic Welding was published in the Issue 25 of September 2005 of Practical Welding Letter. To read the article Click on PWL No. 25. An Article on Tandem GMA Welding and Surfacing was published in Issue 52 of Practical Welding Letter for December 2007.
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The Welding_arc equipment is designed for semiautomatic, all position welding, or automatic mainly for welding in flat position. It should be noted that this process was originally developed for welding aluminum, magnesium and stainless steels in order to provide high deposition rate economically. Alternating current is seldom used. Constant voltage power supplies of either the motor generator type or of the transformer rectifier type are currently used. However some are provided with means of changing the slope of the volt-ampere curve, for limiting the amount of the surge current drawn when short circuiting. Welding_arc electrode holders provide sliding electric contact to the moving consumable electrode wire, and must be cooled either by air or by water circulation. For manual or semiautomatic use the torch or gun (as is sometimes called) should be lightweight and include a trigger for starting and stopping operation. An Article on Programming for Mechanized and Robot Welding was included in our Practical Welding Letter No. 06 of February 2004. To read the article click on PWL#006. To receive all the issues of PWL as they are published, please Subscribe. Finally the best known... In GAS TUNGSTEN ARC WELDING (GTAW), called also Tig for Tungsten Inert Gas Welding_arc equipment the electrode is non consumable, but it wears out and needs replacement from time to time. The Welding_arc torch is made for manual use, except that for special applications automated welding can be performed with proper accessories as needed. See our new page. Click on Tig Welding Tips Power supplies are similar to those described for Welding_arc SMAW but include also provisions for regulating and starting argon flow and water flow to be supplied to the torch for cooling. High frequency spark production is a useful accessory for pilot arc starting without contacting the work. This is a dangerous practice to be avoided, likely to introduce tungsten fragments into the weld and also, if necessary, for providing arc stabilization during welding. Special provisions permit the use of pulsed high current rapidly rising and decaying with high pulse repetition rate: this kind of welding current is useful for quality joining of precision parts with high penetration and no drop through but need special education and training of welders, or establishment of precise welding procedures. For welding sensitive materials like nickel-base and cobalt-base alloys it may be useful to employ Welding_arc provisions that permit the gradual decay of current at the point of arc extinction, to avoid the appearance of crater cracks at the end of the bead. The tig torch is a precise, compact and lightweight piece of Welding_arc equipment which performs a set of functions while being light to hold and easy to manipulate:
This all in one option gives you AC/DC Tig and Stick capability for steel, stainless steel and aluminum. Hobart TIGMATE AC/DC Stick and TIG Welding Package - 230/380 Volt, 52/39 Amp, Fingertip Control, Model# 500424 For a complete description see the Owner's Guide downloadable from
Non consumable electrodes of different sizes and materials are listed in:
When a continuous joint has to be welded, automatic GTAW can be performed by providing workpiece to torch relative motion with or without filler metal supplied by a motor driven wire feed device. Centering of the torch on the joint is critical to the success of the operation, as are pre-cleaning and set up. An Article on Hot-Wire TIG Welding was published (7) in Issue 50 of Practical Welding Letter for October 2007. Click on PWL#050 to read it.
Last but not least... PLASMA ARC WELDING (PAW) equipment is very similar to GTAW, except that the Welding_arc torch produces a constricted arc between the tungsten electrode and a constricting orifice. It results in higher arc temperature, a concentrated heat distribution and a higher arc voltage. A powerful stream of plasma, that is of very hot ionized gas, is directed into the workpiece. The stream of gas can produce a hole in the joint (called a keyhole), permitting welding of thicker plates with thinner beads at higher speeds, and providing economic solutions for a specific class of joints. This Welding_arc equipment is usable with all common materials except those with low melting temperature and low boiling point like lead and zinc. See a new page on Plasma Welding Tips. The main drawback imputable to plasma Welding_arc is more elevated cost, which can be justified only by better quality (less scrap) and higher productivity. For very thin applications, a specially designed type of equipment called microplasma is available which permits efficient control of the weld. You may wish to explore the following link: LTPDC2000D Lotos Pilot Arc IGBT 50A Plasma Cutter /200A Tig/Stick Welder with Stick aluminum feature
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