Welding GuideLEARNING TO STICK WELDRefer tohttp://www.lincolnelectric.com/safetyfor additional safety information.Welding SafetyInteractive Web Guidefor mobile devicesLTW2 Issue Date 07/13 Lincoln Global, Inc. All Rights Reserved.
Safety DepenDS on youThe serviceability of a product or structure utilizing this type ofinformation is and must be the sole responsibility of the builder/user.Many variables beyond the control of The Lincoln Electric Companyaffect the results obtained in applying this type of information. Thesevariables include, but are not limited to, welding procedure, platechemistry and temperature, weldment design, fabrication methods,and service requirements.WARNINGThis statement appears where the information must be followedexactly to avoid serious personal injury or loss of life.CAUTIONThis statement appears where the information must be followed toavoid minor personal injury or damage to this equipment.Keep youR heaD out of the fumeSDON’T get too close to the arc. Usecorrective lenses if necessary tostay a reasonable distance awayfrom the arc.READ and obey the Material SafetyData Sheet (MSDS) and the warninglabel that appears on all containersof welding materials.USE ENOUGH VENTILATION orexhaust at the arc, or both, to keepthe fumes and gases from your breathing zone and the general area.IN A LARGE ROOM OR OUTDOORS, natural ventilation may beadequate if you keep your head out of the fumes (see below).USE NATURAL DRAFTS or fans to keep the fumes away from yourface.If you develop unusual symptoms, see your supervisor. Perhaps thewelding atmosphere and ventilation system should be checked.weaR coRRect eye, eaR & boDy pRotectionPROTECT your eyes and face with welding helmetproperly fitted and with proper grade of filter plate(See ANSI Z49.1).PROTECT your body from welding spatter and arcflash with protective clothing including woolenclothing, flame-proof apron and gloves, leatherleggings, and high boots.PROTECT others from splatter, flash, and glare withprotective screens or barriers.IN SOME AREAS, protection from noise may beappropriate.BE SURE protective equipment is in good condition.ALSO, WEAR SAFETY GLASSES IN WORKAREA AT ALL TIMES.SpeciaL SituationSDO NOT WELD OR CUT containers or materials which havepreviously been in contact with hazardous substances unless they areproperly cleaned. This is extremely dangerous.DO NOT WELD OR CUT painted or plated parts unless specialprecautions with ventilation have been taken. They can release highlytoxic fumes or gases.Additional precautionary measuresPROTECT compressed gas cylinders from excessive heat, mechanicalshocks, and arcs; fasten cylinders so they cannot fall.BE SURE cylinders are never grounded or part of an electrical circuit.REMOVE all potential fire hazards from welding area.ALWAYS HAVE FIRE FIGHTING EQUIPMENT READY FORIMMEDIATE USE AND KNOW HOW TO USE IT.
LEARNING TO STICK WELDTABLE OF CONTENTSPageLearn to Stick Weld .1Arc Welding Circuit.1What Happens in the Arc .1Correct Welding Position.2Correct Way to Strike an Arc .2Correct Arc Length .2Practice .3Common Metals.3Joint Types and Positions.4Butt Joint.4Penetration .4Fillet Joint.4Multi Pass Welds .5Welding in the Vertical Position .5Vertical-Up Welding .5Vertical-Down Welding .5Overhead Welding .6Welding Sheet Metal.6Hardfacing .6How to hardface the Sharp Edge.6Hardfacing of Idler and Roller .7Welding Cast Iron .7Cast Iron Plate Preparation .83
LEARNING TO STICK WELDLEARNING TO STICK WELDNo one can learn to weld simply by reading about it. Skillcomes only with practice. The following pages will help theinexperienced welder to understand welding and develophis skill. For more detailed information, order a copy of“New Lessons in Arc Welding”, available from the James F.Lincoln Foundation.the aRc-weLDing ciRcuitThe operator’s knowledge of arc welding must go beyond the arcitself. If you want to get the most out of your welding practice, yourknowledge of welding must go beyond the arc. You also need tounderstand how to control the arc, and this requires knowledge of thewelding circuit and the equipment that provides the electric currentused in the arc. Figure 1 is a diagram of the welding circuit. Thecircuit begins where the electrode cable is attached to the weldingmachine and ends where the work cable is attached to the weldingmachine. Current flows through the electrode cable to the electrodeholder, through the holder to the electrode and across the arc. On thework side of the arc, the current flows through base metal to the workcable and back to the welding machine. The circuit must be completefor the current to flow. To weld, the work clamp must be tightlyconnected to clean base metal. Remove paint, rust, etc. as necessaryto get a good connection. Connect the work clamp as close aspossible to the area you wish to weld. Avoid allowing the weldingcircuit to pass through hinges, bearings, electronic components orsimilar devices that can be damaged.This arc-welding circuit has a voltage output of up to 79 volts, whichis enough to shock.The electric arc is made between the work and the tip end of a smallmetal wire - the electrode - which is clamped in a holder. The holderis held by the welder.What Happens in the Arc?Figure 2 illustrates the action that takes place in the electric arc. Itclosely resembles what is actually seen during welding.FIGURE 2—The welding arcThe “arc stream’’ is seen in the middle of the picture. This is theelectric arc created by the electric current flowing through the spacebetween the end of the electrode and the work. The temperature ofthis arc is about 6000 F. (3315 C.), which is more than enough tomelt metal. The arc is both very bright and very hot. If you look at thearc with your naked eye, you risk several hours’ or days’ worth ofpain and poor, blurry vision. A welding helmet with a very dark lens,specifically designed for arc welding, must be used whenever viewingthe arc.Have you ever watched water flow from a garden hose onto soft soilor earth? Eventually, the water will build up enough to displace anddig into the soil beneath it. It may even form a small crater that thenfills with water. The arc works the same way, melting the base metaland actually digging into it as it moves across the surface of the basemetal. The molten metal forms a molten pool or crater and tends toflow away from the arc. As it moves away from the arc, it cools andsolidifies. A slag forms on top of the weld to protect it during cooling.WARNINGELECTRIC SHOCK CAN KILL.CAREFULLY REVIEW THE ARC WELDINGSAFETY PRECAUTIONS AT THE BEGINNINGOF YOUR OPERATOR’S MANUAL.ARC RAYS CAN BURNEYES AND SKIN.when uSing an open aRc pRoceSS, it iSneceSSaRy to uSe coRRect eye, heaD anDA gap is made in the welding circuit (see figure 1) by holding the tip of boDy pRotection.the electrode 1/16-1/8” away from the work or base metal beingPROTECT YOURSELF AND OTHERS, READwelded. The electric arc is established in this gap and is held and“ARC RAYS CAN BURN” AT THE FRONT OF THEmoved along the joint to be welded, melting the metal as it is movedOPERATOR’S MANUAL SUPPLIED WITH THEArc welding is a manual skill requiring a steady hand, good physicalWELDER.condition, and good eyesight. The operator controls the welding arcand, therefore, the quality of the weld made .To electrical(earth) ground.FIGURE 1—The welding circuit for Shielded MetalArc Welding(SMAW)1
LEARNING TO STICK WELDThe function of the covered electrode is much more than simply tocarry current to the arc. The electrode is composed of a core of metalwire around which has been extruded and baked a chemicalcovering. The core wire melts in the arc, and tiny droplets of moltenmetal shoot across the arc into the molten pool. The electrodeprovides additional filler metal for the joint to fill the groove or gapbetween the two pieces of the base metal. The covering also melts orburns in the arc. It has several functions. It makes the arc steadier,provides a shield of smoke-like gas around the arc to keep oxygenand nitrogen in the air away from the molten metal, and provides aflux for the molten pool. The flux picks up impurities and forms theprotective slag. The principal differences between various types ofelectrodes are in their coatings. By varying the coating, it is possibleto greatly alter the operating characteristics of electrodes. By understanding the differences in the various coatings, you will gain a betterunderstanding of selecting the best electrode for the job you have athand. In selecting an electrode, you should consider the followingaspects:2. The Correct Way to Strike an ArcBe sure the work clamp makes good electrical contact tothe work.Lower your autodarkening or fixed shade welding helmet.Scratch the electrode slowly over the metal and you will seesparks flying. While scratching, lift the electrode 1/8"(3.2mm) to establish the arc.NOTE: If you stop moving the electrode while scratching,the electrode will stick.NOTE: Most beginners try to strike the arc by making a fast jabbing motiondown onto the plate. Result: They either stick or their motion is so fastthat they break the arc immediately.3. The Correct Arc LengthThe arc length is the distance from the tip of the electrodecore wire to the base metal.1. The type of deposit you want, e.g. mild steel,stainless, low alloy, hardfacingOnce the arc has been established, maintaining the correctarc length becomes extremely important. The arc should beshort, approximately 1/16 to 1/8" (1.6 to 3.2mm) long. As theelectrode burns off, it must be fed to the work to maintaincorrect arc length.2. The thickness of the plate you want to weld3. The position it must be welded in (downhand, out ofposition)4. The surface condition of the metal to be weldedThe easiest way to tell whether the arc has the correctlength is by listening to its sound. A nice, short arc has adistinctive, “crackling” sound, very much like eggs frying ina pan. The incorrect, long arc has a hollow, blowing orhissing sound.5. Your ability to handle and obtain the desiredelectrodeThe following four simple manipulations are of prime importance.Without complete mastery of these four, further welding is more orless futile. With complete mastery of the four, welding will be easy.4. The Correct Welding SpeedThe important thing to watch while welding is the puddle ofmolten metal right behind the arc. Do NOT watch the arcitself. It is the appearance of the puddle and the ridge wherethe molten puddle solidifies that indicate correct weldingspeed. The ridge should be approximately 3/8" (9.5mm)behind the electrode.1. The Correct Welding PositionAt first, you may find it easier to use the two-handedtechnique shown below. This requires the use of a weldinghelmet.a. Hold the electrode holder in your right hand.The tendancy is to weld too fast, resulting in a thin, uneven,“wormy” looking bead. Watching the molten metal.b. Touch your left hand to the underside of your right.c. Put the left elbow against your left side.(For welding left-handed it is the opposite.)If you are using a hand shield, hold the electrode holder inyour right hand and the hand shield in your left. (For weldingleft-handed it is the opposite.)Whenever possible, weld from left to right (if right-handed).This enables you to see clearly what you are doing.IMPORTANT: For general welding it is not necessary to weave the arc; neitherforwards and backwards nor sideways. Weld along at a steady pace. Youwill find it easier.Hold the electrode at a slight angle as shown.NOTE: When welding on thin plate, you will find that you will have to increasethe welding speed, whereas when welding on heavy plate, it is necessaryto go more slowly in order to get good penetration.2
LEARNING TO STICK WELDPRACTICECommon MetalsMost metals found around the farm or small shop are lowcarbon steel, sometimes referred to as mild steel. Typicalitems made with this type of steel include most sheet metal,plate, pipe and rolled shapes such as channels, angle ironsand “I’’ beams. This type of steel can usually be easilywelded without special precautions. Some steel, however,contains higher carbon. Typical applications include wearplates, axles, connecting rods, shafts, plowshares andscraper blades. These higher carbon steels can be weldedsuccessfully in most cases; however, care must be taken tofollow proper procedures, including preheating the metal tobe welded and, in some cases, carefully controlling thetemperature during and after the welding process. Forfurther information on identifying various types of steels andother metals, and for proper procedures for welding them,we again suggest you purchase a copy of (“New Lessons inArc Welding” available from the James F. Lincoln arcwelding foundation).Use the following exercise to spend a little more time practice in thefour skills that enable you to maintain:1. Correct Welding Position2. Correct Way To Strike An Arc3. Correct Arc Length4. Correct Welding SpeedUse the following:Mild Steel Plate 3/16" (4.8mm) or heavierElectrode 1/8" (3.2mm) Fleetweld 180Current Setting: 105 Amps AC or 95 Amps DC( )Do the following:1.Learn to strike the arc by scratching the electrode overthe plate. Be sure the angle of the electrode is correct.Use both hands.2.When you can strike an arc without sticking, practicethe correct arc length. Learn to distinguish it by itssound.3.When you are sure that you can hold a short, cracklingarc, start moving. Look at the molten puddle constantly,and look for the ridge where the metal solidifies.4.Run beads on a flat plate. Run them parallel to the topedge (the edge farthest away from you). This gives youpractice in running straight welds, and also, it gives youan easy way to check your progress. The 10th weld willlook considerably better than the first weld. Byconstantly checking on your mistakes and yourprogress, welding will soon be a matter of routine.Regardless of the type of metal being welded, it is importantin order to get a quality weld that it be free of oil, paint, rustor other contaminants.3
LEARNING TO STICK WELDJOINT TYPES ANDPOSITIONSPenetrationUnless a weld penetrates close to 100%, a Butt Joint will be weakerthan the material welded together.Five types of welding joints are: Butt joint, Fillet joint, Lap joint, Edgejoint and Corner joint. See Figure 3.FIGURE 3Of these, the Butt Joint and Fillet Joint are the two most commonwelds.In this example, the total weld is only 1/2” (12.5mm) the thickness ofthe material; thus the weld is only approximately half as strong as themetal.Butt jointLap jointIn this example, the joint has been flame beveled or ground prior towelding so that 100% penetration could be achieved. The weld, ifproperly made, is as strong or stronger than the original metal.Edge jointFillet jointCorner jointButt JointsPlace two plates side by side, leaving 1/16” (1.6mm) (for thin metal)to 1/8” (3.2mm) (for heavy metal) space between them in order to getdeep penetration.Securely clamp or tack weld the plates at both ends, otherwise theheat will cause the plates to move apart. See Figure 4.Fillet JointsWhen welding a Fillet Joint, it is very important to hold the electrodeat a 45 angle between the two sides, or the metal will not distributeitself evenly.To make it easy to get the 45 angle, it is best to put the electrode inthe holder at a 45 angle, as shown:FIGURE 4Now weld the two plates together. Weld from left to right (if righthanded). Point the Stick electrode between the two plates, keepingthe Electrode Holder tilted in the direction of travel.Weld DirectionWatch the molten metal to be sure it distributes itself evenly on bothedges and in between the plates. This is referred to as the “pulltechnique”. On thin gauge sheet metal, use the “push technique”.4
LEARNING TO STICK WELDMultiple Pass Weldsmetal. As soon as it has solidified, the arc is SLOWLY broughtback, and another few drops of metal are deposited. DO NOTFOLLOW THE UP AND DOWN MOVEMENT OF THE ARC WITH THEEYES. KEEP THEM ON THE MOLTEN METAL.8. When the arc is brought back to the now solidified puddle, ITMUST BE SHORT, otherwise no metal will be deposited, thepuddle will melt again, and it will “drip.”9. It is important to realize that the entire process consists of SLOW,DELIBERATE movements. There are no fast motions.Make multiple pass horizontal fillet joints as shown in the sketch. Putthe first bead in the corner with fairly high current. Hold the electrodeangle needed to deposit the filler beads as shown putting the finalbead against the vertical plate.Vertical-Down WeldingVertical-down welds are applied at a fast pace. These welds aretherefore shallow and narrow, and as such are excellent for sheetmetal. Do not use the vertical-down technique on heavy metal. Thewelds will not be strong enough.1. Use 1/8” (3.2mm) or 3/32" (2.4mm) Fleetweld 180 electrode.Welding in the Vertical Position2. On thin metal, use 60-75 amps. (14 ga 75 amps — 16 ga 60amps.)Welding in the vertical position can be done either vertical-up orvertical-down. Vertical-up is used whenever a large, strong weld is3. Hold the electrode in a 30-45 angle with the tip of the electrodedesired. Vertical-down is used primarily on sheet metal for fast, lowpointing upwards.penetrating welds.4. Hold a VERY SHORT arc, but do not let theelectrode touch the metal.Vertical-Up Welding5. An up and down whipping motion will helpprevent burn-through on very thin plate.The challenge, when welding vertical-up, is to put the molten metalwhere it is wanted and make it stay there. If too much molten metal is 6. Watch the molten metal carefully.deposited, gravity will pull it downwards and make it “drip.’’The important thing is to continue lowering the entire arm as the weldTherefore a certain technique has to be followed:is made so the angle of the electrode does not change. Move theelectrode so fast that the slag does not catch up with the arc.Vertical-down welding gives thin, shallow welds. It should not be usedon heavy material where large welds are required.1. Use 1/8" (3.2mm) at 90-105 amps or 3/32" (2.4mm) at 60 ampsFleetweld 180 electrode.2. When welding, the electrode should be kept horizontal or pointingslightly upwards. (See drawing.)3. The arc is struck and metal deposited at the bottom of the twopieces to be welded together.4. Before too much molten metal is deposited, the arc is SLOWLYmoved 1/2”-3/4" (12.5-19mm) upwards. This takes the heataway from the molten puddle, which solidifies. (If the arc is nottaken away soon enough, too much metal will be deposited, andit will “drip.’’)5. The upward motion of the arc is caused by a very slight wristmotion. The arm must NOT move in and out, as this makes theentire process very complicated and difficult to learn.6. If the upward motion of the arc is done with a correct wristmotion, the arc will automatically become a long arc thatdeposits little or no metal. (See drawing.)7. During this entire process the ONLY thing to watch is the molten5
LEARNING TO STICK WELDOverhead WeldingHow to Hardface the Sharp Edge (Metal to Ground Wear)Various techniques are used for overhead welding. However, in the1. Grind the share, approximately one inch (25mm) wide along theinterest of simplicity for the inexperienced welder the followingedge, so the metal is bright.technique will probably take care of most needs for overhead welding: 2. Place the share on an incline of approximately 20-30 . The1. Use 1/8" (3.2mm) at 90-105 amps or 3/32" (2.4mm) at 60 ampseasiest way to do this is to put one end of the share on a brick.Fleetweld 180 electrode.(See drawing.)2. Put the electrode in the holder so it sticks straight out.Most users will want to hardface the underside of the share, butsome might find that the wear is on the top side. The important3. Hold the electrode at an angle approximately 30 off vertical,thing is to hardface the side that wears.both seen from the side and seen from the end.3. Use 1/8" (3.2mm) Wearshield ABR electrode at 90-105 amps.Strike the arc about one inch (25mm) from the sharp edge.4. The bead should be put on with a weaving motion, and it shouldbe 1/2” to 3/4" (12.5 to 19mm) wide. Do not let the arc blowover the edge, as that will dull the edge. (See drawing.)The most important thing is to hold a VERY SHORT arc. (A longarc will result in falling molten metal; a short arc will make themetal stay.)If necessary — and that is dictated by the looks of the moltenpuddle — a slight back and forth motion along the seam with theelectrode will help prevent “dripping.”5. Use the back-stepping method. Begin to weld 3" (75mm) fromthe heel of the share and weld to the heel. The second weld willbegin 6" (150mm) from the heel, the third weld 9" (225mm) fromthe heel, etc.Welding Sheet MetalWelding sheet metal presents an additional problem. The thinness ofthe metal makes it very easy to burn through. Follow these fewsimple rules:1. Hold a very short arc. (This prevents burn through, sincebeginners seem to hold too long an arc.)2. Use 1/8” (3.2mm) or 3/32" (2.4mm) Fleetweld 180 electrode.3. Use low amperage. 75 amps for 1/8" (3.2mm) electrode, 40-60amps for 3/32" (2.4mm) electrode.4. Move fast. Don’t keep the heat on any given point too long. Keepgoing. Whip the electrode.5. Use lap welds whenever possible. This doubles the thickness ofthe metal.BACK-STEPPINGBack-stepping greatly reduces the chances for cracking of the share,and it also greatly reduces possible warpage.NOTE: The entire process is rather fast. Many beginners go much too slowlywhen hardfacing plow shares, running the risk of burning through the thinmetal.HardfacingThere are several kinds of wear. The two most often encountered areas follows:1. Metal to Ground Wear(Plowshares, bulldozer blades, buckets, cultivator shares, andother metal parts moving in the soil.)2. Metal to Metal Wear(Trunnions, shafts, rollers and idlers, crane andmine car wheels, etc.)Each of these types of wear demands a different kind ofhardsurfacing electrode.When the proper electrode is applied, hardsurfacing can more thandouble the service life of the part. For instance, hardsurfacing ofplowshares results in 3-5 times more acreage plowed.6
LEARNING TO STICK WELDHardfacing of Idler and Roller (Metal to Metal Wear)Welding Cast IronA very common application of hardfacing for metal to metal wear isthe hardfacing of idlers and rollers and the rails that ride on theserollers and idlers.The reason for hardfacing these parts is primarily monetary. A fewdollars worth of electrode will completely build up a roller or idler, andthe hard surface will outlast several times the normal life or suchrollers and idlers.If the below procedure is followed, it is not even necessary to removethe grease bearing while welding. This will save a lot of time.1. The roller (or idler) is inserted on a piece of pipe that is resting ontwo sawbucks. This enables the operator to turn it while welding.2. Use Wearshield BU electrodes, 5/32" (4.0mm) at 175 amps or3/16" (4.8mm) at 200 amps.3. Weld across the wearing surface. Do not weld around.4. Keep the roller (or idler) cool by quenching with water, and bystopping the welding periodically. This will prevent shrinking ofthe roller (or idler) on the grease bearing.5. Build up to dimension. The weld metal deposited byWearshield BU electrode is often so smooth that machining orgrinding is not necessary.When welding on a piece of cold cast iron, the tremendous heat fromthe arc will be absorbed and distributed rapidly into the cold mass.This heating and sudden cooling creates WHITE, BRITTLE cast iron inthe fusion zone.This is the reason why welds in cast iron break. Actually, one piece ofthe broken cast iron has the entire weld on it, and the other piece hasno weld on it.In order to overcome this, the welding operator has two choices:1. Preheat the entire casting to 500-1200 F. (260-649 C). If thecast iron is hot before welding, there will be no sudden chillingwhich creates brittle white cast iron. The entire casting will coolslowly.2. Weld 1/2" (12.5mm) at a time, and not weld at that spot againuntil the weld is completely cool to the touch.In this way, no large amount of heat is put into the mass.NOTE: The quenching of the roller (or idler) has another purpose: it increasesthe hardness — and thus the service life — of the deposit.The hardfacing of the rails is a lot easier:1. Place the rails with the side that rides on the rollers and idlersupwards.2. Use Wearshield BU electrodes, 5/32" (4.0mm) at 175 amps or3/16" (4.8mm) at 200 amps.3. Build up to size.4. Do not quench. This will make the deposit slightly softer than thedeposit on the idlers and rollers. That means that the wear willprimarily be on the rails, which are a lot easier and less timeconsuming and cheaper to build up.If you have no way of preheating large castings, you’ll probably find iteasier to use the second of the two methods discussed above.However, smaller castings can easily be preheated before welding byusing a forge, stove, fire, or Arc Torch.When using the 1/2" (12.5mm) at a time method, it is recommendedto start 1/2" (12.5mm) away from the previous bead and weld into theprevious bead (backstepping).After welding Cast Iron, protect the casting against fast cooling. Put itin a sand (or lime) box.If sand or lime is not available, cover it with sheet metal or any othernon-flammable material that will exclude drafts and retain heat.NOTE: The same electrode — Wearshield BU — will give the operator twodesired hardnesses, just by a difference in cooling rate, making it possibleto put the hardest deposit on the most expensive parts.NOTE: The outside of the rails (the side that comes in contact with the ground)should be surfaced with Wearshield ABR, since this side has Metal toGround wear.Cast Iron Plate PreparationWherever practical, the joint to be welded should be “veed” out bygrinding or filing to give complete penetration. This is especiallyimportant on thick castings where maximum strength is required. Insome instances, a back-up strip may be used and plates may begapped 1/8" (3.2mm) or more.On sections where only a sealed joint is required and strength is notimportant, the joint may be welded after slightly veeing out the seamas shown.7
LEARNING TO STICK WELD8
cuStomeR aSSiStance poLicyThe business of The Lincoln Electric Company is manufacturing andselling high quality welding equipment, consumables, and cuttingequipment. Our challenge is to meet the needs of our customers andto exceed their expectations. On occasion, purchasers may askLincoln Electric for advice or information about their use of ourproducts. We respond to our customers based on the best informationin our possession at that time. Lincoln Electric is not in a position towarrant or guarantee such advice, and assumes no liability, withrespect to such information or advice. We expressly disclaim anywarranty of any kind, including any warranty of fitness for anycustomer’s particular purpose, with respect to such information oradvice. As a matter of practical consideration, we also cannot assumeany responsibility for updating or correcting any such information oradvice once it has been given, nor does the provision of informationor advice create, expand or alter any warranty with respect to the saleof our products.Lincoln Electric is a responsive manufacturer, but the selection anduse of specific products sold by Lincoln Electric is solely within thecontrol of, and remains the sole responsibility of the customer. Manyvariables beyond the control of Lincoln Electric affect the resultsobtained in applying these types of fabrication methods and servicerequirements.Subject to Change – This information is accurate to the best of ourknowledge at the time of printing. Please refer towww.lincolnelectric.com for any updated information.
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