Ac polarity welding

Ac polarity welding

This means that Being a newbie in stick welding, I've seen some electrodes that work well in DCEN and AC (for example 7018 and 6013). 0 165 19 60/13 9/28 Bead appearance 1st side T By ERIN ANDERSON Welding Technology Program INTRODUCTION Gas Tungsten Arc Welding (GTAW) can be performed using three shallow. com/welding-with-dc-straight-reverse-polarityWelding with DC Straight and Reverse Polarity To understand welding with DC straight and reverse polarity, it is important to understand the electrical arc welding circuit,24/1/2018 · Though AC itself has no polarity, when AC electrodes are used on DC they usually operate best on one the correct polarity must be used when welding with any given metallic electrode. EN is often considered the welding side of the AC waveform, while EP is where the cleaning or oxide removal occurs. While AC output has become a lot more stable in recent years, many welders still swear by DC as the Holy Grail of currents. AC current reverses its polarity 120 times per second and that cannot be changed. Because the current doesn’t change polarity, you’ll generally get a smoother welding output. electrodes with 308 and 304 stainless base metal. If you take a pitcher of water and pour it into a glass, the glass receiving the water gets most of the friction. As previously mentioned, this prevents aluminum oxide from building up and contaminating the weld. An electrode polarity chart based on AC or DC current and type of Stick welding electrode. Arc blow problems can also have external causes, such as windy conditions. I've noticed that Lincoln Electric MIG welders uses DC for welding aluminum. In alternating current (AC) welds of long duration, Tig-welding-tips: Alternating Current (AC) In Alternating Current (AC) polarity is inverted at every cycle. com/ for a detailed article about tig welding polarity click here http://goo. SAW (Submerged Arc Welding) is done both with DC+ and AC (especially with extremely high currents e. If you have a choice between AC and DC, you may choose to only use the AC setting when Creating High-Quality Stick Welds: A User's Guide for the type and size electrode you are welding with and that the polarity is correct. For completeness, information is given here about the MIG/MAG and submerged arc process and the influence of polarity. This condition yields a stable arc, smooth metal transfer, relatively low DC or AC Stick Welding? It’s an ever-changing debate that’s evolved as welding itself has advanced. DC+ will mean the current flows from the electrode to the base metal. E7018 AC All position welding electrode for AC or DC reverse polarity current-3/32″ Job Pk. Many power sources have "max penetration" indicated when more If you want to avoid this headache, then make sure you switch your MIG welding polarity settings any time you change from solid wire to flux core wire. The torch is connected to the negative terminal of the power source and the work lead is connected to the positive Name two methods used to change DC polarity on a welding machine. For this reason, DCEN polarity is the most common choice for TIG welding when the cleaning action of the DCEP process is not needed. Use the proper base metal cleaning If you are confused by welding terminology like “Reverse Polarity” and “Straight Polarity”, this blog will be a basic primer to help you understand the basics of polarity and where and how to use them. 6 110 13 60/7 6/15 3. Welds can be accomplished using different energy sources from a gas flame or electric arc Grainger carries a broad selection of TIG welders and stick welders from well-known brand-name manufacturers like Miller Electric, Westward, Lincoln Electric and more. ” These Sheet Metal Welding Conference XI Sterling Heights, MI May 11-14, 2004 1 ENERGY CONSUMPTION IN AC AND MFDC RESISTANCE SPOT WELDING Wei Li University of Washington Eugene Feng Welding Technology Corporation Daniel Cerjanec and The Forney 30686 7018 AC 1/8 in. AC polarity depth of penetration. 07 0. Alternating current, or AC, is used for welding aluminum with a TIG welder. So in this case the Polarity Welding current (A) Preheating temp ( C) Interpass temp ( C) Plate thickness (mm) Groove angle ( )/root opening (mm) Pass sequence (layers/passes) 2. Louis – to welders it means polarity. Cold re strikes are no problem with this versatile, all-position electrode. 0 165 19 60/13 9/28 Bead appearance 1st side T 8/1/2019 · AC? DC? This electrode performs beautifully either way. ALTERNATING CURRENT. Running a rod on DCEP, or Reverse Polarity is the standard polarity for MIG and for Stick welding. 9Small amount of slag remains on the finished weld but is difficult to remove. AC, known as alternating current, changes polarity evenly; on Use thicker material, change the joint design or switch the welding process to AC TIG. –1/4 in. This current changes direction many times a second. com. Stick welding - selecting polarity Keep in mind this is stick ONLY and Tig requires DCEN ONLY or AC. Eliminate/reduce gaps. 09GAZ TUNGSTEN ARC WELDING: Electrical current and polarity …www. Increase the voltage to get into spray transfer. It is an extremely useful stick welding power source for maintenance repair, fabrication, construction, erecting and hardfacing applications. That is also known as DCEN (DC electrode negative) or "straight" polarity for those with older welders. In case of DC polarity, current flows only in one direction; whereas, in case of AC, current flow direction reverses in every cycle (number of cycles per second depends on the frequency of supply). Incorrect polarity will cause poor penetration, irregular bead shape rapid Polarity DC TIG Welding is carried out with the torch negative and the work positive. The welding books i have dont mention this at all, or maybe i didnt read thoroughly. (3. With DC polarity, the welding circuit can be either straight or reverse. -AS shown in figure 8-5, ac welding is actually a combination of DCSP and DCRP; however, the electrical characteristics of the oxides on the metal often prevent the current from flowing smoothly in the reverse polarity half of the cycle. Polarity in welding has to do with the direction of the current in the welding process. With Miller's innovative QuickTech technology, setup and changing processes is even easier. Know When to Choose Between AC and DC in Welding read more. dc welding circuits. With DCEN, the negative terminal inside your machine is hooked up to your electrode (your MIG gun) while the positive terminal is hooked up to your ground. The polarity of MIG is the reverse of normal TIG. 05 0. Basically, if you are welding aluminum you need AC (with hi-freq) and other metals are done with DC straight polarity (DCEN). Table 1. Most Technical Highlight KOBELCO WELDING TODAY 3 How Electric Polarity Affects Weld Quality in Arc Welding DCEP AC DCEN AC DCEP AC DCEN AC DCEP DCEP AC DCEN AC DCEP AC DCEN AC DCEP The term “polarity” is used to describe the electri-cal The Lincoln Electric AC/DC 225/125 Welder features both AC and DC welding arcs with broad output ranges for versatile use. Claims for warranty must be made within 90 days of the date of purchase. 9Good penetration due to forceful arc. DC, also known as direct current, has a constant, single-directional, polarity. Stick welding is polarity driven. 2%PS, TS and IV between AC and DCEP. Since the electrons are running in both directions the transformer output has no polarity. For Lecture 7 Physics of Welding Arc III This chapter presents the different forces acting in a typical welding arc zone and their effect on welding. The frequency is 50 hertz or cycles per second in Europe and 60 Hz in the USA. This not only allows the operator to start and stop without leaving the work but also to adjust the current while welding. For TIG the negative torch helps avoid overheating the tungsten. Alternating current requires a voltage about halfway between DCEP and DCEN polarity and is particularly useful when arc blow is a problem. The choice of current and polarity depends on the A simplified explanation of basic direct current welding polarity showing the current flow, and the heat produced in the workpiece or the electrode. 53 kg). Tensile strength 70,000 PSI. If aluminum material is to be dealt with then you must bring the polarity at the AC setting. MIG Welding Reverse Polarity TIP TIG Welding is always better quality than TIG and 100 to 500% faster with superior quality than TIG - MIG - FCAW. Reverse Polarity or Straight Polarity? Which one is in your wallet When welding with the SMAW process, it is a good idea to have an understanding of what type of polarity is best suited for the electrode you are using. The choice of current and polarity depends on the process, the type of electrode, the arc atmosphere and the metal being welded. In the arc welding process, the heat required is obtained from electrical energy. polarity AC - • Arc length (Voltage) • Weld travel speed • Oscillation • Filler addition • Shielding gas composition &flow rate-generallyArorHe ormixtures. Descriptions in BOLD are as they appear in the Lincoln Electric Price Book. Effects of polarity on the weld. The covering on the elctrode designates whcih polarity is best and all manufacturers specify on the electrode container what polarity is recommended. . Some Stick Welding Technique, SMAW Welding Parameter, Polarity AC DC in SMAW Welding, and other. When you are welding in AC polarity, the weld has an electrode-negative (EN) cycle and an electrode-positive (EP) portion of the cycle. On the 8/2/2013 · Aluminum alloys are typically welded on AC with the gas tungsten arc welding (GTAW) process. ” You will see that welding machines and electrodes are labeled AC or DC, which describe the polarity of the welding machine’s current. called straight polarity. Some welders Beardsley emphasizes AC is almost always a secondary choice. You have to use a lot bigger A lot of AC current changes its polarity 120 times per second with a 60 hertz current. g. Welding is a hands-on job, but welders still have to have a fair amount of technical knowledge. Most welders don't bother changing polarity because their other jobs run on DC positive. That's not the machine for arc welding aluminum. Whereas Do you know what AC (Alternating Current) and DC (Direct Current) signify on your welder and electrodes? These terms basically describe the polarity of the E6010 and E6011 are AWS classifications for Shielded Metal Arc Welding (SMAW) stick electrodes. It is often used in tandem arc systems in which DCEP is used on the leading electrode and AC on the trailing electrode in order to minimise magnetic interaction between the two arcs. The arc blow causes the arc to wander while you are using large coated electrodes or welding in corners on heavy metal. AC stands for Alternating Current and means that the electric charge travels in one direction half of the time and the opposite direction for the other half. The difference between AC and DC welding is the polarity of electrons that is emitted from the welding tool during the process. Both alternating current and direct current are used for TIG welding, the deciding factor being the base metal to be welded. Stickweld. To take advantage of polarity, the negative one-half cycle AC, Linear The Effects of Polarity on the Resistance 3. DC on the other hand can either be positive or negative polarity. Many people give up on flux core because they don't get the polarity right. In MIG, if it uses gas only, without a flux or metal core, it will require electrode positive. When the arc goes out, the slag freezes on the end of the rod, which is why your first attempts look like, pardon the expression, 'bird droppings'. You can sometimes find one for about 1700 bones. Minimum tensile strength (1000s of psi) Position of welding. 61 1. There are several ways to weld, but the two most popular ways to weld at home include gas metalHOW POLARITY AFFECTS SAW Submerged Arc Welding (SAW) Current Type DCSP (Straight) Current Type DCRP (Reverse) Current Type AC Electrode Polarity Negative Electrode Polarity Positive Electrode Polarity Alternating Heat Distribution If its like stick or SMAW how come you cant use AC. "Though AC itself has no polarity, when AC electrodes are used on DC they usually operate best on one specific polarity. TIG welding just like Stick welding uses two polarity types when welding using Direct Current and they are: DC Direct Current Electrode (-) Negative. With AC welding machines polarity is not problem Polarity in DC power Electric from ENGNEERING EMC 1113 at HCT Abu Dhabi Womens College E7018 AC All position welding electrode for AC or DC reverse polarity current-1/8″-Job Pk. As previously mentioned, this prevents aluminum How DC TIG Welding Polarity Works To better understand the flow of DC current you need to think of it in terms of water flowing. GAW Gas-shielded arc welding GTAW Gas-shielded tungsten arc welding GMAW Gas-shielded metal arc welding AHW Atomic hydrogen welding CAW Constricted arc welding TIG Tungsten inert-gas arc welding MIG Metal inert-gas arc welding MAG Metal active-gas arc welding PJW Plasma jet welding PAW Plasma arc welding DCR, AC DCR, DCS, AC F, V, OH, H F 2 For welding carbon moly steels E8018-C3 DCR, AC F, V, OH, H For low alley, high-tensile strength E10013-G DCS, AC F, V, OH, H For low alloy, high-tensile steels DCR – Direct Current Reverse Polarity DCS – Direct Current Straight Polarity AC – Alternating Current E-6010. A welder should know the meaning of polarity, and recognize what effect it has on the welding process. It’s just one direct current. The alternating current between positive and negative polarity enables a steadier arc when welding magnetic parts. 7 2. 53 kg). 35 1. To have this advantage of unequal hit distribution in electrode and base metal, the polarity is an important factor for successful welding. Welding machine checked for functionality. Know when AC current is the best choice. One half of the complete ac cycle is DCSP and the other half is DCRP. The part labelled ‘B’ in the figure is known as (a) weld preparation (b) penetration (c) reinforcement (d) slag 6. This will help you choose the right stick for the welding job. A lot of important information that all TIG welders should know about current, burning in electrode negative, as well as symmetric and asymmetric sine waves and how your welding …作者: DoRite Fabrication觀看次數: 7. In case of DC polarity, current flows only in one direction; whereas, in case of AC 8 Aug 2018 AC and DC are terms that refer to the polarity of the electrical current that the welding machine creates and runs through the electrode. 23/9/2014 · Visit the weldmonger store here http://weldmongerstore. The use of DCEP for TIG welding necessitates larger diameter tungsten electrodes and water-cooling, and is most commonly used as only part of the cycle in AC welding. Table 1shows an example of the effect of polarity on chemical composition and mechanical properties of weld metal. Yes it can be done on DCEN with pure helium. In this FCAW welding energy source using a DC or AC electric current drawn from power plants or through a transformer or rectifier. Great prices & free shipping on orders over USD50! Shielded metal arc welding (SMAW), also known as manual metal arc welding (MMA or MMAW), flux shielded arc welding or informally as stick welding, is a manual arc welding process that uses a consumable electrode covered with a flux to lay the weld. DCR, AC DCR, DCS, AC F, V, OH, H F 2 For welding carbon moly steels E8018-C3 DCR, AC F, V, OH, H For low alley, high-tensile strength E10013-G DCS, AC F, V, OH, H For low alloy, high-tensile steels DCR – Direct Current Reverse Polarity DCS – Direct Current Straight Polarity AC – Alternating Current Description: Top Features AC polarity welding Low open circuit voltage operation Minimal spatter Capable of cold re-strikes Typical Applications General fabrication Tack and skip welds Thin sections Welding Positions All, except vertical down Best Answer: DC+ = electrode positive or reverse polarity DC- = electrode negative or straight polarity Basically, the polarity tells you where the heat is concentrated whether it is in the base metal or the electrode. The benefits of an AC/DC machine should not be overlooked in your decision-making, especially if your welding aspirations go beyond the amateur home shop realm. Can Results in more spatter and sparks during welding. With the exception of the rods that run AC, polarity will also have some effect on the penetration value of the rod. Amperage 90-165 Amps AC, DCEP, DCEN (Either Polarity). Welding is the process of using electrical current to superheat and melt metal so that you can join two pieces of metal together. POLARITY. also turn the main welding current on and off at the same time. Choose from AC stick welders, DC welding machines and AC/DC welders and more, offered in a 19/3/2011 · what is reverse polarity?and what is the differance between a 2 roller feed and a 4 roller feed?which would be perfered and why? thank you for your helpPolarity in resistance spot welding has to do with the direction of the current flow in the welding process. If you’re not sure what the difference is between using solid MIG welding wire, and gasless (or flux core wire The Effects of Polarity on the Resistance Welding Process NUGGET S 1/2 Volume 3/No. Plasma arc welding: how it works A brief account of the physical principles of PAW By Arthur Nunes July 19,2004 The physical principles of PAW from basic arcs to keyholing to variable polarity are outlined. reverse polarity is used to bear greater advantage in (a) overhead welding (b) flat welding … Flux Core Arc Welding (FCAW) is Welding arc electric wire their flux (protective central core). You’re either using a negative polarity or a positive polarity but never both during a weld. com Welding Types | Welding Machines | welding processes MENU Weldingis. GMAW (MIG) − Welding − (40 Hours Course) With technical assistance from: GERMAN DEVELOPMENT SERVICE August 2000 Dear Reader, I would like to comment this handout, because otherwise you might get a little confused while studying it. For TIG welding stainless steel, you got to put the polarity setting at the DC Electrode Negative setting which is also given by DCEN. An AC/DC welder is recommended for Stick. The. Posted – 2-17-2011. When the machine is set for straight polarity, the current flows from the When TIG welding, there are three choices of welding current. They are: Direct Current Straight Polarity, Direct Current Reverse Polarity, and Alternating Current with High Frequency stabilization. SMAW is the most versatile welding process in terms of polarity The large variety of coating fluxes for covered electrodes enable the SMAW process to be the most versatile in terms of polarity. Ideal for jobs that require top arc-welding performance, the welder can be used for maintenance repair, fabrication, construction and other 4. The majority of covered electrodes use either AC or DCEP. I wanted to see where AC fits into the picture. Welding - GTAW (Gas Tungsten Arc Welding) study guide by derekdosen includes 28 questions covering vocabulary, terms and more. The 6013 rods are all-position AC or DC polarity for welding new, clean sheet metal applications because they penetrate less but don’t burn through the metal. Regarding AC or DC for cast iron welding, it depends. 1000 amps) Then you have CC and CV machines, and when does one use AC? Basically, DC+ makes the electrode hot and the work cold (this is reverse polarity) and DC- makes the work hot and the electrode cold (this is straight polarity). There are three types of choices we can have 9/7/2009 · Your going to have a vary hard time stick welding aluminum with with a 120v ac arc welder. For MIG/MAG welding, DCEN and AC are Arc-Welding Introduction Arc welding is the fusion of two pieces of metal by an electric arc between the pieces being joined Power sources produce DC with the electrode either positive or negative, or AC. Most rods are designed or can run on DCEP. 2 AC 130 None ≤ 150 5/10 4. com/joining/welding/polarity/difference-betweenArc welding power sources can supply either AC or DC or both forms of current. Switch welding polarity. In arc welding, d. In brief, the electric current type effect and the polarity in direct current (DC-) on the features of the bead that the welding is schematized on the below figure : Effect of the balance control in AC mode on the bead features Reverse Polarity - In electric welding, the term refers to a DC setup where the work is made negative, and is called DCRP. First of all, not everyone who can Tig weld, can Tig weld aluminum. 4V, 45 Percent/ 15 to 90A @ 23. Text and photos by Tom Hintz. (4. There are two ways to position your lead those are straight polarity and reversed polarity. In rare situations you may use electrode negative, for example stick welding unusually thin materials. com – welders, welding, metalworking Welders, equipment, and more! Skip to content Home24/4/2001 · Even if you are experienced in welding steels, aluminum welding can present quite a challenge. Dirty welds Use a push angle instead of a drag technique. Arc welding power sources can supply either AC or DC or both forms of current. 30 0. Type of Coating, Current & Polarity . For stick welding with DC the polarity is usually "electrode positive" as well. An arc is produced between the tip …DC – = direct current – straight polarity AC = alternating current OCV = open circuit voltage Chemical symbols Al Aluminium B Boron C Carbon Cr Chromium Co …Tungsten Inert Gas (TIG or GTA) Welding - Job Knowledge 6 Tungsten inert gas (GTA or TIG) welding Contact Us HF is also important in stabilising the AC arc; in AC, electrode polarity is reversed at a frequency of about 50 times per second, causing the arc Next, you will need to connect the foot pedal with the unit. (3) $ 6. The 7018 welding rods are used for pipe welding and structural steel welding and repair welding. Thanks that of cast iron. The results The advantage of a (AC) transformer welding machine: The main advantage of (AC) transformer welding machine is the freedom from arc blow. 6 V, 20 Percent, Input (Amps) 20, Output Range 13/12/2017 · The main concept of fusion welding is the partial melting and fusion of the joint between two members and a filler metals may be used. Also, DCEP polarity causes excessive heating of the tungsten electrode. FCAW is a combination of process GMAW welding, SMAW, and SAW. If the welding arc was AC the fine particles from the melting wire wouldn't be attracted to the metal being welded 100% of the time. pdf · PDF 檔案In the TIG welding, the type of welding current AC or DC and also the polarity, straight “normal” (DC-, DCEN) or reverse (DC+, DCEP); depend GAZ TUNGSTEN ARC WELDING: Electrical current and polarity The TIG process (GTAW) provides a better protection Stick Welder, Series ES 95i, Input Voltage 120VAC, Polarity DC, Amps DC 95, Welding Processes Stick, TIG, Rated Output DC: 95A/13. When welding aluminum, the best DC polarity to use to clean the The AC/DC 225/125 is an arc welding power source with an AC welding output range of 40-225 amps and a DC welding output range of 30-125 amps. Polarity Stick Welding Electrodes/Rods Numbers, meanings and uses. Welding in AC. Quick Welding Tip: DC Polarities Made Easy 6011 Vs 6013 BEST POLARITY for WELDING AC is good for welding material that is magnetized to eliminate arc blow. The arc is enveloped by a stream of inert gas. Aluminum's oxide coating, higher thermal conductivity, and lower melting point easily can lead to welding problems unless you know how to prepare for welding …For all intents and purposes, DC welding is the preferred type of welding. SMAW Welding Is Same With Stick Welding, Manual Metal Arc (MMA), and Flux Shielded Arc Welding. To take advantage of polarity, the negative one-half cycle AC, Linear The Effects of Polarity on the Resistance A/C Alternating Current like the current in your home. Order ESAB Stick Welder, ES 95i Series, DC Polarity, W1003210 at Zoro. About two thirds of the heat goes to the positive side or the arc. MIG welding (with gas) is done with what is called reverse polarity, which is electrode (torch) positive, work (clamp) negative. 5 The Advantages and Disadvantages of AC and DC Welding Plants . The AC current is mainly recommended for the welding of aluminum, magnesium and their alloys, beryllium-copper, etc. " 1. 2KPolarity Welding With Dc Straight And Reverse Polarity : …翻譯此網頁mewelding. Note: AC current is really not a polarity as the current itself reverses polarity 60 times per second – 60 hertz. Internal Components of a Welding Machine. P 26 (GTAW: Current Polarity It is used for welding carbon steel and is also used for welding any type of polarity. When the machine is set for straight polarity, the current flows from the electrode to the weld surface and createsThe difference between AC and DC welding is the polarity of electrons that is emitted from the welding tool during the process. Welding involves creating an electric arc between an electrode and the metal that is being welded. If you use the wrong polarity for a certain welding rod, your weld strength will not be very good. With direct current (DC) the welding circuit can either be straight, or reverse polarity. 05 PN: 11072 Add to cart E7018 AC All position welding electrode for AC or DC reverse polarity current-1/8″ 1 lb. Shielded Metal Arc welding is the process of joining two metal pieces using a flux covered electrode which is melted in an electric arc and becomes a fused part of the pieces being welded. 67 Use on AC or DC reverse polarity welding current. AC/DC. Effects of polarity and selection of polarity in arc welding. When Heliarc (aka TIG) welding and the electrode isn't deposited into the weld, the direction of the flow of electrons is very important. With AC power source, in half of the cycle electrode becomes negative and in next half of the cycle, electrode becomes positive. Flux core needs to have knurls on the feed rollers to feed well. By ERIN ANDERSON Welding Technology Program INTRODUCTION Gas Tungsten Arc Welding (GTAW) can be performed using three different polarity types: Direct Current Electrode Negative (DCEN), Direct Current Electrode Positive (DCEP), and Alternating Current (AC). Its one of those things that really sets a welder apart . AC is good for welding material that is magnetized to eliminate arc blow. ac polarity welding When TIG welding aluminum, you us AC current and when the AC wave is in the negative phase you get cleaning action as contaminates flow from the base material to the electrode. Reverse Polarity - In electric welding, the term refers to a DC setup where the work is made negative, and is called DCRP. 6V, 40ipm wire, 13. DC TIG Welding is carried out with the torch negative and the work positive. Polarity switch, if any, set to DC reverse. Dual Plasma and TIG processes Automatic welding applications Performance and high productivity in vessel and pipe work. 0 September 2014 Table of Contents Unit Objective . Unfortunately, reverse polarity doesn't provide good weld penetration. Some welders AC is good for welding material that is magnetized to eliminate arc blow. Consumables: stick electrodes. 2 Variable polarity TIG or squarewave AC ensures continuous deoxidation, a high-quality weld bead with total control of the weld pool for What’s the Difference Between Reverse and Straight Polarity When you see the letters AC/DC on your welder, If you use the wrong polarity for a certain welding rod, your weld strength will not be very good. Your AC welder doesn't work with aluminum stick electrodes because the arc is extinguished every time the polarity switches from (+) to (-). Apr 24, 2017 Whether you are using electrode-positive (DC+) or electrode-negative (DC–) polarity, DC tends to produce a smoother weld than AC. AC (Alternating Current) and DC (Direct Current) is used to describe the polarity of the electric current that the welder generates and in what direction it travels. • AC/DC TIG: 24 ga. For most applications, DC reverse polarity welding offers advantages over AC, including easier starts and out-of-position welding, smoother arc and fewer arc outages and sticking. DC is 13/12/2017 · The main concept of fusion welding is the partial melting and fusion of the joint between two members and a filler metals may be used. 2, May 2000/rev. Electrode. Cable terminals checked for tightness. ac polarity weldingArc welding is a welding process that is used to join metal to metal by using electricity to create Arc welders can use either direct (DC) or alternating (AC) current, and consumable or non-consumable electrodes. Further, influence of electrode polarity in welding has been described in respect of arc stability, heat generation and cleaning action on weld metal. minaprem. Filler metal is primarily obtained from the electrode core. straight or reverse polarity welding current. Dc welding is the choice here's why. Easy slag removal. Whether you are using electrode-positive (DC+) or electrode-negative (DC–) polarity, DC tends to produce a smoother weld than AC. 5ipm travel. to have dissimilar junctions in welding. With AC welding machines polarity is not problem Polarity in DC power Electric from ENGNEERING EMC 1113 at HCT Abu Dhabi Womens College GTAW Welding Aluminum with Alternating Current - High Frequency. For most Aluminum welding tasks, You need alternating current. Coarse and fine adjustment List three types of controls that might be used to set the fine amperage on ac or dc welding machines. Stick electrodes from Lincoln Electric are designed for mild and low alloy steel welding applicationsWith electrodes that can accommodate AC, the polarity is not an issue, but with those that use DC current, one can weld either by using reverse or straight polarity. With AC balance you will be tig welding aluminum better than without Welding on Reverse polarity heats the electrode up a lot and balls it as you see in the photo above. Use the proper base metal cleaning Polarity Welding current (A) Preheating temp ( C) Interpass temp ( C) Plate thickness (mm) Groove angle ( )/root opening (mm) Pass sequence (layers/passes) 2. The general terms associated with polarity are reverse polarity and straight polarity. The wire in MIG welding is disposable, but you want to hang onto the TIG tungsten so the larger tungsten compensates a little for the fact you are frying it with the wrong polarity. To understand welding with DC straight and reverse polarity, it is important to understand the electrical arc welding circuit, which is the same as any electrical circuit. Stick welding (SMAW =shielded metal arc welding) electrodes (sticks/rods) are designed for use with specific current types, either AC, DC and some rods can be used with either. In a direct current electrode negative (DCEN) circuit, the current flows from the Use thicker material, change the joint design or switch the welding process to AC TIG. A/C Alternating Current like the current in your home. The EP portion of the cycle will be as though you were welding reverse polarity, and 2/3 of the heat goes into the tungsten. is to change to AC MIG welding unlike most other welding processes has one standard voltage type and polarity type. In AC welding, the arc's action when the electrode is positive and the workpiece is negative, called reverse polarity, breaks up the oxide on the surface of the aluminum, making welding much easier. CHARACTERISTICS OF CURRENT TYPES FOR GAS TUNGSTEN ARC WELDING DC STRAIGHT POLARITY DC REVERSE POLARITY AC HIGH FREQUENCY SHIELD GAS SELECTION AND USE SHIELD GAS SELECTOR CHART welding process and polarity associated with welding arc. Dual shield and metal core can vary. reverse polarity is used to bear greater advantage in (a) overhead welding (b) flat welding … Best Answer: DC+ = electrode positive or reverse polarity DC- = electrode negative or straight polarity Basically, the polarity tells you where the heat is concentrated whether it is in the base metal or the electrode. While AC/DC might make most reminisce about a certain era of rock music – I know I listened to plenty of the band’s music on KSHE 95 in St. These Hobart Stick Welding Electrodes are stainless steel 3/32in. 20 terms Welding Polarities study guide by tlinkenhoker includes 10 questions I was wondering how you calculate the welding heat input when you are using the variable polarity TIG process? I'm not running true AC (50/50). Figure 10-2. 95% of the time you will use electrode positive. In order from deepest penetration to lowest does the order go as follows Abstract Influence of direct current electrode positive (DCEP) duty ratio in variable polarity (VP) arc welding of aluminum has been investigated in the current work. --Reverse polarity and straight polarity. In a direct current electrode positive (DCEP) circuit, the current flows from the workpiece to the electrode. 4. May someone knows for sure. Experience the advantages of Waveform Control Technology™ in Submerged Arc Welding Lecture 7 Physics of Welding Arc III This chapter presents the different forces acting in a typical welding arc zone and their effect on welding. C. Mig and Fluxcore are also polarity dependent but don't Reverse Polarity or Straight Polarity? Which one is in your wallet. These two types are very similar but the main difference 24 Apr 2017 Whether you are using electrode-positive (DC+) or electrode-negative (DC–) polarity, DC tends to produce a smoother weld than AC. Tagged with: ac welder, Direct Current, high chromium content, reverse polarity, stainless rods, weld stainless steel, welding stainless steel About the author Ed 7 thoughts on “Useful Tips for Welding Stainless Steel” to have dissimilar junctions in welding. So, for gasless MIG welding polarity (when using flux core wire), your MIG welding polarity settings should be set to direct current electrode negative (or DCEN). An arc is produced between the tip …Plasma and TIG processes Automatic welding applications Performance and high productivity in vessel and pipe work. Many power sources have "max penetration" indicated when more than 50% of the AC cycle is spent on electrode negative polarity and "max cleaning" when more than Difference between AC and DC Welding Machines What Is Welding? Welding is a process used to join metals together by melting the parts and using a filler to form a joint. 175 mm) diameter rod 10 lbs. Arc welding power sources provide either AC or DC power; however, depending on the connection made, DC power can provide two polarities – straight polarity and reverse polarity, as provided below. Choosing the right polarity is part of the process of setting up a TIG welding machine for best effect,and is Tuesday, March 5, 2019 Alternating current, or AC, is used for welding aluminum with a TIG welder. The penetration by AC is also more than with straight polarity but less than that of the reversed. ecollege. 175 mm) diameter rod 10 lbs. 2015年1月22日Beardsley emphasizes AC is almost always a secondary choice. Every welding process has a preferred polarity. The arc blow often occurs when welding with direct current machines. In Here will be share about What is Shield metal arc welding, Stick Welding Machine Parts, Electrode, Stick Welding Technique, SMAW Welding Parameter, Polarity AC DC in SMAW Welding, and other. • Automatically determines the polarity. It is the opposite of DCSP, or straight polarity. AC/DC CC welding from 24-gauge to ½ inch thickness at 45 to 235 amps Dinse style connection provides easy polarity change and cable repairs Larger work envelope 1. Electrode Polarity Chart ELECTRODE DC* AC POSITION PENETRATION USAGE 6010 EP--ALL DEEP MIN. . So the example E-6010 would be an Electrode with 60,000 psi tensile strength, all position, with a cellulose sodium coating, DC reverse polarity. Whereas DC delivers a constant and consistent current SMAW is the most versatile welding process in terms of polarity The large variety of coating fluxes for covered electrodes enable the SMAW process to be the most versatile in terms of polarity. welding 2/3 rd of the hit is liberated from the positive end and 1/3 rd from the negative end. For alu welding with a DC TIG you can go electrode (tungsten) positive, but you have to use a thumping big electrode. 9Rutile-based flux. Why GMAW uses mostly DCEP The vast majority of gas metal arc welding (GMAW) applications use DCEP. Importance of polarity in welding: In D. watch video on DCEN TIG welding aluminum here. Again, if AC is your only choice just be sure you are using rods made specifically for AC welding. Quizlet flashcards, activities and games help you improve your grades. It could equally be attracted back to the contact tip. Other AC welding rods include 6013, 7018 and 7024. You need to select the polarity as Single arc AC welding increases productivity over single arc DC+ polarity welding, with increased resistance to arc blow. A great choice for low open circuit voltage AC power sources. characteristics of current types for gas tungsten arc welding dc straight polarity dc reverse polarity ac high frequency shield gas selection and use shield gas selector chart 4guide for shield gas flows, current settings, cup selection tungsten selection and preparation tungsten electrode selector chart tungsten preparation Alternating current, or AC, is used for welding aluminum with a TIG welder. In brief, the electric current type effect and the polarity in direct current (DC-) on the features of the bead that the welding is schematized on the below figure : Effect of the balance control in AC mode on the bead features Alternating current, high-frequency (ACHF) welding is a combination of dc straight polarity and dc reverse polarity. The electrodes deliver smooth, tough welds with the strength, corrosion and crack resistance needed for welding stainless steel in all positions. For tougher jobs, you might need in excess, but for mild ones you must not press it too hard. When straight, the current travels from the electrode to the welding surface, heating the metal. December 2015 9 9 1-4 72 NUGGET S TECHNICAL APPLICATION BRIEF At the atomic level, with the AC coming out of your transformer there is a herd of electrons which all run one way, then stop, turn round and run the other way half a cycle later. Probably splatter all over kind of like what flux-core sometimes does because it's run reversed polarity. It would first depend on the exact electrode involved and there are many available. Washington Alloy Nickel 99 is specifically suited for repairing cracked or porous be used in any position utilizing AC or DC (reverse polarity) APPLICATIONS Commonly used on gears, motor housings, machine parts, farm equipment, large . The general terms associated with polarity are 30/3/2003 · Discussion has been on going in the forum on Direct Current welding polarity and its effects on penetration. Either way, that setup is a good starting point for general purpose welding on things that don't need to be pretty to work. Welding is a process in which two pieces of metal are joined together using heat and electricity. Proof of purchase 5/5(1)供貨狀態: 有庫存價格: $27. Without regard for welding process in this argument and specific process variables, lets concider strictly SMAW for this discussion. DCEP, or Reverse Polarity is the standard polarity for MIG and for Stick welding. Arc welders can use either direct (DC) or alternating (AC) current, and consumable or non-consumable electrodes. Each of these has its applications, advantages, and DC welding offers advantages over AC for most stick applications, including: easier starts; fewer arc outages and easier vertical up and overhead welding; easier to learn; and a smoother arc. In case of DC polarity, current flows only in one direction; whereas, in case of AC, current flow direction reverses in every cycle (number of cycles per second depends on the frequency 12/4/2015 · AC is good for welding material that is magnetized to eliminate arc blow. Running a rod on Negative polarity tends to have a shallow penetration (good for thin metal) whereas running on Postive polarity will give have deeper penetration. Miller makes the Polarity Reversing Switch (043942) to change or isolate the polarity from AC to DC (or vice versa) within the Miller Big Blue 400 or 500 diesel welding generator. The system can be configured for single, tandem, or multi-arc applications with up to five arcs. The voltage used is DC direct current, much like the current in a car battery. Basic Tips to Improve Stick Welding; provides about 10 percent more penetration at a given amperage than AC, while DC straight polarity (electrode negative) welds Front mounted AC/DC polarity switch & full range amperage switch Easy to weld on a variety of metals using different electrodes The Lincoln Electric AC/DC 225/125 Welder features both AC and DC welding arcs with broad output ranges for versatile use. — Polarity is the direction of the flow are for light-shielded metal-arc welding and for inert-gas arc welding. 5. In case of direct current (DC) welding, when electrode is connected to the negative terminal and workpiece is connected with positive terminal of the power source then it is termed as direct connected to 8/3/2019 · Download Citation on ResearchGate | Variable AC polarity GTAW fusion behavior in 5083 aluminum | Aluminum alloys are typically welded on AC with the gas tungsten arc welding (GTAW) process. Understanding is usually (but not always) superior While using ac, the arc tends to stop during the half cycle in which the electrode becomes____. For all intents and purposes, DC welding is the preferred type of welding. Mig and Fluxcore are also polarity dependent but don't So, for gasless MIG welding polarity (when using flux core wire), your MIG welding polarity settings should be set to direct current electrode negative (or DCEN). A brief description of each polarity type is shown in Table 1. VP arc adopts alternate current (AC) of DCEP and direct current electrode negative (DCEN) as power Find Welding Polaritys related suppliers, manufacturers, products and specifications on GlobalSpec - a trusted source of Welding Top Features AC polarity welding Low open circuit voltage operation Minimal spatter Capable of cold re-strikes Typicalwelds Thin 29/6/2012 · "Though AC itself has no polarity, when AC electrodes are used on DC they usually operate best on one the correct polarity must be used when welding with any given metallic electrode. The penetration by AC is also more than with straight polarity but less than that of the reversed For many people, AC/DC gets them reminiscing about a certain era of rock music, but for welders it means polarity. Comparison among AC, DCRP, and DCSP. Alternating current (AC) flows half the time in one direction and half the time in the other, changing its polarity 120 times per second with 60-hertz current. I'm not very clear on the mechanism but that's what I've read. Flux core penetrates better with gas (reverse DCEP here). 66M2 U3 Manual Metal Arc Welding - Solas eLearninglocal. Direct current (DC) is used on most stick welding Concept of polarity in arc welding – Direct Current Straight Polarity (DCSP), Direct Current Reverse Polarity (DCRP) and Alternating Current (AC) or reversing polarity – their advantages and disadvantages. This simple bit of advice makes understanding the different names of the two DC welding polarities easy. Electrode positive or reversed polarity (from the AC current) will typically result in a deeper penetration through a metal. These two types are very similar but the main difference Aug 8, 2018 AC and DC are terms that refer to the polarity of the electrical current that the welding machine creates and runs through the electrode. DC welding generally has more advantages over AC welding but the most important thing for a welder to understand is how polarity works so that the welder can choose the proper electrode with the right polarity for the job. Proof of purchase required. gl/85bxaA This is part 3 of Tig welding basics. It will provide you with a mechanism to control the heat produced for welding. The factors was study in type of polarity on alternating current (AC), direct current electrode negative (DCEN) and direct current electrode positive (DCEP), levels of welding current for DCR, AC DCR, DCS, AC F, V, OH, H F 2 For welding carbon moly steels E8018-C3 DCR, AC F, V, OH, H For low alley, high-tensile strength E10013-G DCS, AC F, V, OH, H For low alloy, high-tensile steels DCR – Direct Current Reverse Polarity DCS – Direct Current Straight Polarity AC – Alternating Current APPLICATION Power Wave AC/DC Submerged Arc The Power Wave AC/DC welding system is designed to provide superior results over a wide range of Submerged Arc applications. A BASIC GUIDE OF ARC WELDING ELECTRODES INTRODUCTION Ac current changes it's polarity 120 times a second by it's self and can not be changed as can DC current. (4) $ 7. They are also for general-purpose alternating current (at) arc welding power supplies including capacitor discharge, direct current, and inverter type units, current flows in only one direction throughout the welding cycle and hence the Peltier effect is consistent throughout the welding pulse. AC welding switches polarity 60 times per second and can be thought of as both positive and negative. With TIG the EN portion of the AC is just like you were welding straight DC, and 2/3 of the heat goes into the workpiece. CONTENTS: Parts and function of welding machine (SMAW) Procedures in setting –up of welding machines Procedure in checking welding machine functionality. c. THE EXHAUST MANUFACTURING COMPANY THAT MIG AC works with flux core, but DC is cleaner if you have good control over your feed and heat. Skip to content Weldingis. It can be done using different energy sources, from a gas flame or electric arc to a laser or ultrasound. g. • Welding through medium amounts of paint, rust, dirt. Secondly, many electrodes which specify a specific polarity or current MAY also be use nearly as effectively in another mode. An analogy is to think of a welding circuit as a basic DC electrical circuit-The welding machine as the voltage source and the welding arc as the resistance. Discussion has been on going in the forum on Direct Current welding polarity and its effects on penetration. DC- (DCEN or straight polarity) the electrode is "colder" and the TALAT Lecture 4201 Arc Welding Processes: TIG, Plasma Arc, MIG 36 pages, 47 figures Basic Level prepared by Ulrich Krüger, Schweißtechnische Lehr- und Versuchsanstalt Berlin Objectives: − to describe the arc welding processes TIG, Plasma, MIG and Figure 8-5. 63 Provides high strength and toughness without cracking down the center of the bead. Welding involves creating an electric arc Though AC itself has no polarity, when AC electrodes are used on DC they usually operate best on one specific the correct polarity must be used when welding with any given metallic electrode. 8V/20 Percent, Duty Cycle 60A @ 22. Arc welding processes may be manual, semi-automatic, or fully automated. Fast freezing or rapid solidification of the weld metal facilitates welding in the vertical or overhead positions. DC uses either straight polarity, which is electrode negative or reverse polarity, which is electrode positive. Electrode positive or reversed polarity DC welding generally has more advantages over AC welding but the most important thing for a welder to understand is how polarity works so current (AC) is used, the polarity changes every half cycle of 50 or 60 Hz. A filler material is used to form a pool of molten metal that cools to become a strong joint between the pieces. Welding consists of two pieces the work (what your welding on) and the electrode (weld metal) . 2 Variable polarity TIG or squarewave AC ensures continuous deoxidation, a high-quality weld bead with total control of the weld pool for TALAT Lecture 4201 Arc Welding Processes: TIG, Plasma Arc, MIG 36 pages, 47 figures Basic Level prepared by Ulrich Krüger, Schweißtechnische Lehr- und Versuchsanstalt Berlin Objectives: − to describe the arc welding processes TIG, Plasma, MIG and Spray transfer diagram of semiautomatic flux cored arc welding equipment figure 10 56 graph of welding output on ac polarity note that 120 times per second the crosses centerline reing zero erage or no attractive wire types position everything you need to know If its like stick or SMAW how come you cant use AC. It is sometimes Do you know what AC (Alternating Current) and DC (Direct Current) signify on your welder and electrodes? Well, basically these terms describe the polarity of E6010 and E6011 are AWS classifications for Shielded Metal Arc Welding (SMAW) stick electrodes. 13 Mar 2018 Since AC is half positive and half negative, its welding properties are right in the middle of DC positive and DC negative polarity. Figure 8-4. Direct Current Straight Polarity (DCSP) or Direct Current Electrode Negative (DCEN)—When electrode is connected with the negative terminal of the DC welding generally has more advantages over AC welding but the most important thing for a welder to understand is how polarity works so that the welder can choose the proper electrode with the right polarity for the job. Applications Of AC Welding: TIG welding aluminum since AC supports welding at a higher temperature. 2 2. " How to Arc Weld. There’s a lot ofFor SMAW, E-6022 Deck rods are done on AC or DC-SAW (Submerged Arc Welding) is done both with DC+ and AC (especially with extremely high currents e. DCEN is used while welding steel, stainless steel, copper, titanium, gold, and pretty much any other material that can be welded with the exceptions of aluminum and magnesium, which are welded using AC. Welding is the process of joining metals by melting the parts and then using a filler to form a joint. With AC/DC polarity, the electrical current travels back and forth continuously between the electrode and the welding surface. Effect of welding polarity on bead geometry, microstructure, microhardness, and residual stresses of 1020 steel 158 but it had limited effect on the type of microstructures developed in the weld area. The penetration by AC is also more than with straight polarity but less than that of the For many people, AC/DC gets them reminiscing about a certain era of rock music, but for welders it means polarity. AC or DC electrode positive (reverse) polarity. In the standard transformer power supply the heat of the arc, because of alternate polarity, is evenly distributed between electrode and workpiece. However, for creating the best welds, it’s important 3/9/2016 · Here's the second installment of the class I teach on TIG welding for Lincoln Electric. Gas Tungsten Arc Welding (GTAW) process utilizes heat generated by an electric arc maintained between the workpiece and a nonconsumable ungsten electrode. Here is a very brief account of the physics of PAW with an eye to the needs of a welder. Alternating Current (AC) polarity in arc welding AC polarity offers advantages of both DCEN and DCEP; however, to some extent only. steel and aluminum The Multimatic 220 AC/DC comes equipped with all accessories to weld any process, unlike other machines where you need to purchase additional accessories. The welding area DC- polarity results in less penetration and a higher electrode melt-off rate. 67 Related products. 1 Learning Outcome . Similarities between DCSP and DCRP polarities in arc welding Both DCSP and DCRP can be applied for joining of two or more components together; however, the result may be substantially While mainly about MMA welding, polarity is discussed for a range of arc welding processes. In these test results, marked differences are recognized in carbon, oxygen, 0. arc welding GTAW or TIG Tungsten Argon gasHigh Steady Submerged arc welding SAW Solid wire Argon gas High Steady Power sources produce DC with the electrode either positive or negative, or AC. 1000 amps) 22/2/2017 · Welcome to WeldingWeb. Variable polarity (VP) arc welding is known as an effective solution for aluminum thanks to the cleaning effect, which means oxide removal, during the DCEP (direct current electrode positive) period. Your right. Thanks In welding, polarity refers to the direction that current flow through a circuit. SMAW - uses a direct current (DC) or an alternating current (AC). How Polarity Affects Electrode Performance in Arc Welding Polarity Si Mn P S OC AC DCEP 0. Incorrect polarity will cause poor penetration, irregular bead E6010 and E6011 are AWS classifications for Shielded Metal Arc Welding (SMAW) stick electrodes. Further, influence of electrode polarity in welding has been described in respect of arc stability, heat generation and Actually I tried a demo for the AC arc welding machine to a big steel fabrication company here in my to take an ice pick, heat it red hot, stab it into a block of ice, I would get good penetraion. Since aluminum welding is so easily accomplished with AC tig units with either high frequency overlay or inverter style welders such as the Everlast PowerTIG series, DC negative torch polarity is the only one used. Information, techniques and tips on How to Weld ,MIG, FCAW, GMAW, MAG , manual/ robot and welding equipment. One of the terms you will hear in class and in the shop a lot is “welding current. 作者: weldingtipsandtricks觀看次數: 146K影片時長: 13 分鐘Difference Between Straight Polarity and Reverse Polarity …翻譯此網頁www. Direct current flows in one direction continuously through the welding circuit. AC polarity is the preferred polarity for MIG welding techniques, reverse polarity ??. Welding using a Lincoln Tig 175 and discussing low end amp starts, what DCEN means, vs DCEP, and why AC is used to tig weld aluminum. Electrical Polarity - Electrons flow naturally from negative to positive and that has an effect in terms of heat when it relates to welding. When welding with the SMAW process, it is a good idea to have an understanding of what type of polarity is best suited for the electrode you are using. The Work Sense Leads are not Lincoln Electric orderable parts. We used this at the paper mill where I worked on conveyors in the chip yard because the chips rubbing across the conveyors would magnetize the metal. Mar 13, 2018 Since AC is half positive and half negative, its welding properties are right in the middle of DC positive and DC negative polarity. Weldreality Home Page. Now you can weld aluminum anywhere you can arc weld, even in poor conditions, without the need for a MIG or TIG torch, special welding wire, hoses, regulators, or expensive and heavy gas bottles. sodel. Polarity. Direct current flows in one direction, from the negative (-) to the positive (+). com/medias/iw/gaz-tungsten-arc-welding-sodel. For stick welding with AC the polarity doesn't really matter. This switch allows you to get past restrictions based upon the polarity of your welder's electrode. The ac welding cycle. 9Very stable arc. TIP TIG Welding Home Page TIG Welding All Weld and Steels Ed's 30/9/2016 · What is Alternating Current (AC)? Chapter 1 - Basic AC Theory Most students of electricity begin their study with what is known as direct current (DC), which is electricity flowing in a constant direction, and/or possessing a voltage with constant polarity. 8/5(83)供貨狀態: 有庫存價格: $587. As mentioned above, Moreover, it can be used either with DC or AC polarity. In ac circuits, the direction of. Whereas Arc welding power sources can supply either AC or DC or both forms of current. One of the terms you will hear in class and in the shop aAC polarity in arc welding. com, the ultimate Source for Welding Information & Knowledge Sharing! As mentioned above, the manufacturer will specify which Polarity DC+, DC-,or AC that their electrodes are designed for, and generally give you a range to run it 10/3/2019 · Polarity in welding has to do with the direction of the current in the welding process. Welding and Polarity Welding is the process whereby metals are melted and a filler used to help I know that on TIG, AC is used for aluminum because the polarity reversal is suppose to help clean the surface. ie/Content/APPRENTICE/liu/pipefitting/pdf/M2_U3 · PDF 檔案Manual Metal Arc Welding Revision 2. The Forney 30686 7018 AC 1/8 in. 6 MMA Welding 22/2/2017 · How to Weld. The welding area is usually protected by some type of shielding gas, vapor, or slag. These two types are very similar but the main difference between the two is with the recommended welding polarity. E6013 Electrode 9Used with AC or DC (either polarity). E6013 is usually described as the “beginner’s rod, “sheet metal rod,” or even “easy rod. Incorrect polarity will cause poor penetration, irregular bead shape , and Welding is a hands-on job, but welders still have to have a fair amount of technical knowledge. com Welding career Welding Symbols 19/7/2018 · When you are welding in AC polarity, the weld has an electrode-negative (EN) cycle and an electrode-positive (EP) portion of the cycle. DC reverse polarity (electrode positive) provides about 10 percent It is Important to Understand Polarity When Welding To Ensure You Get The Best Results. Unfortunately, oxides, scale, and moisture on the work piece often tend to prevent the full flow of current in the reverse polarity direction. Welding with DC Straight and Reverse Polarity. I'm running about 85% DCEN and 15% DCEP, 230 DCEN, 230 DCEP, 80 pulses per second, 10. What is Alternating Current (AC)? Chapter 1 - Basic AC Theory Most students of electricity begin their study with what is known as direct current (DC), which is electricity flowing in a constant direction, and/or possessing a voltage with constant polarity. Flux core (gasless) welding is done with straight polarity, which is electrode (torch) negative, work (clamp) positive. Some special metal welding, such as magnesium alloys, is also carried out using AC. 3. An arc welded joint is shown in the above figure