ELECTRIC ARC / WIRE ELECTRIC ARC / WIRE WIRE WELDINGWIRE WELDING

ARC/WIRE WELDINGARC/WIRE WELDING

OBJECTIVESOBJECTIVESI can identify the main parts of the arc welding I can identify the main parts of the arc welding process.process.

I can associated the terms with welding. I can associated the terms with welding.

I can describe the difference between AC, DC I can describe the difference between AC, DC power inputpower input

I can compare and contrast transformers, I can compare and contrast transformers, rectifiers and AC welding equipment.rectifiers and AC welding equipment.

I can identify electrodes and their applicationI can identify electrodes and their application

I can identify welding equipment, positions and I can identify welding equipment, positions and equipment. equipment.

WORK ANGLE TRAVEL ANGLE

WELDING BASIC

SMAWSMAWSMAW is the AWS name used by the American SMAW is the AWS name used by the American Welding Society for Welding Society for Shielded Metal Arc WeldingShielded Metal Arc Welding..Stick is the most commonly used name for Stick is the most commonly used name for SMAW. This is because the electrode SMAW. This is because the electrode resembles a stick. It is also, often referred to as resembles a stick. It is also, often referred to as manual welding.manual welding.The SMAW process uses constant current power The SMAW process uses constant current power sources.sources.SMAW is the most widely used arc welding SMAW is the most widely used arc welding process in the world.process in the world.All electrode polarities are used: DC-, DC+ and All electrode polarities are used: DC-, DC+ and ACAC

SMAW PROCESSSMAW PROCESSSMAW is a process in which an electric arc is SMAW is a process in which an electric arc is established between the electrically grounded established between the electrically grounded work piece and a 9”-18” length of covered work piece and a 9”-18” length of covered consumable metal rod, called the electrode. consumable metal rod, called the electrode. The heat of the arc melts the base metal in the The heat of the arc melts the base metal in the immediate area, the electrode’s metal core, and immediate area, the electrode’s metal core, and any metallic elements in the coating of the any metallic elements in the coating of the electrode. electrode. It also melts, vaporizes or breaks down It also melts, vaporizes or breaks down chemically non-metallic substances in the chemically non-metallic substances in the coating to shield the arc, protect the weld, and coating to shield the arc, protect the weld, and add alloys or properties to the weld depositadd alloys or properties to the weld deposit

Terms:Terms:

Arc-flowArc-flow of current across a small gap of current across a small gapBase MetalBase Metal -metal to be welded to -metal to be welded toBeadBead --Weld made by one pass of the --Weld made by one pass of the electrodeelectrodeCraterCrater --depression at the end of the weld --depression at the end of the weldPenetrationPenetration --depth of weld into the base --depth of weld into the base metalmetalBevelBevel --cutting the edge of the metal at an --cutting the edge of the metal at an angleangleWeldingWelding --joining of two or more metal by --joining of two or more metal by fusionfusion

TERMSTERMS

ElectrodeElectrode --Metal wire or rod covered --Metal wire or rod covered with a chemical coatingwith a chemical coatingFluxFlux --Chemical coating to protect the --Chemical coating to protect the bead, can be a solid or gas.bead, can be a solid or gas.SpeedSpeed --how fast you are traveling. --how fast you are traveling.SlagSlag --left over carbon on a bead --left over carbon on a bead made by an arc welder. Protects and made by an arc welder. Protects and cools the bead.cools the bead.

Summary of Shielded Metal Summary of Shielded Metal Arc WeldingArc Welding—Why Do IT? —Why Do IT?

SMAW welding has grown tremendously in SMAW welding has grown tremendously in popularity due to all of its advantagespopularity due to all of its advantagesIt is still the most popular welding process in North It is still the most popular welding process in North America.America.SMAW is the most difficult welding process in which SMAW is the most difficult welding process in which to train welders, but it is the foundation of electric to train welders, but it is the foundation of electric arc welding processes. arc welding processes. The equipment is fairly basic and inexpensive The equipment is fairly basic and inexpensive comparatively to any other arc welding process. comparatively to any other arc welding process. A wide variety of base materials, including both A wide variety of base materials, including both ferrous and non-ferrous, can be welded using the ferrous and non-ferrous, can be welded using the SMAW process along with a variety of applications SMAW process along with a variety of applications including sheet metal and thick sections of material.including sheet metal and thick sections of material.

Summary of Shielded Metal Arc Summary of Shielded Metal Arc WeldingWelding—Why Do IT? 2—Why Do IT? 2

The process produces a protective The process produces a protective slag that will need to be removed for slag that will need to be removed for cleanliness and to prevent slag cleanliness and to prevent slag inclusions in multiple pass welds.inclusions in multiple pass welds.The process also produces spatter, The process also produces spatter, which is a visual defect. However, which is a visual defect. However, the spatter can be easily removed the spatter can be easily removed with a grinder.with a grinder.

ARC WELDINGARC WELDINGThere are several advantages to SMAW. There are several advantages to SMAW.

Low Start Up CostsLow Start Up Costs - SMAW welding machines are relativity - SMAW welding machines are relativity inexpensiveinexpensive

PortabilityPortability - SMAW is a very portable process because it does not - SMAW is a very portable process because it does not require any external shielding gas and equipment due to the require any external shielding gas and equipment due to the ability of the electrode to produce its own shielding gases.ability of the electrode to produce its own shielding gases.

Outdoor WeldabilityOutdoor Weldability - SMAW welding can be done outdoors. The - SMAW welding can be done outdoors. The shielding of the weld puddle from the coating of the electrode is shielding of the weld puddle from the coating of the electrode is not susceptible to winds and draft, and therefore, is an excellent not susceptible to winds and draft, and therefore, is an excellent choice for outdoor welding. choice for outdoor welding.

All Position WeldingAll Position Welding - SMAW can be done in all welding positions, - SMAW can be done in all welding positions, which eliminates the need for expensive fixtures or manipulation which eliminates the need for expensive fixtures or manipulation of the part being welded.of the part being welded.

Variety of MaterialsVariety of Materials - Many base materials and alloys can be - Many base materials and alloys can be welded with the SMAW process.welded with the SMAW process.

DISADVANTAGESDISADVANTAGES Low EfficiencyLow Efficiency - The efficiency of a SMAW electrode can be - The efficiency of a SMAW electrode can be

defined as the percentage of the electrode that is consumed defined as the percentage of the electrode that is consumed and becomes part of the weld. SMAW electrodes are 60%-and becomes part of the weld. SMAW electrodes are 60%-65% efficient. The primary reason for this low efficiency is 65% efficient. The primary reason for this low efficiency is stub loss, or the portion of the electrode that is unused and stub loss, or the portion of the electrode that is unused and discarded. .discarded. .Operating FactorOperating Factor - Operating factor can be defined as the - Operating factor can be defined as the amount of arc on time in a shift of work, labeled as a amount of arc on time in a shift of work, labeled as a percentage. SMAW welding has an operating factor of percentage. SMAW welding has an operating factor of approximately 25% - 30%--workday is spent arc welding.approximately 25% - 30%--workday is spent arc welding.RestartsRestarts - SMAW electrodes are only 9”-18” in length. When - SMAW electrodes are only 9”-18” in length. When the electrode is consumed in the arc, it needs to be replaced the electrode is consumed in the arc, it needs to be replaced with a new one. This means that welding stops, and time is with a new one. This means that welding stops, and time is taken to replace each electrode. taken to replace each electrode. Operator SkillOperator Skill - SMAW welding requires a high level of - SMAW welding requires a high level of operator skill. This process is one of the hardest arc welding operator skill. This process is one of the hardest arc welding processes to learn.processes to learn. Slag & SpatterSlag & Spatter . .

Welding EquipmentWelding EquipmentWeldersWeldersAC (Alternating Current)--Current alternates AC (Alternating Current)--Current alternates direction, between positive & negative. direction, between positive & negative. DC (Direct Current)--Current flows in one DC (Direct Current)--Current flows in one directiondirectiona.    DC Positive (STRAIGHT)a.    DC Positive (STRAIGHT)– Electrode negative, work positiveElectrode negative, work positive

b.    DC Negative(REVERSE)b.    DC Negative(REVERSE)– Electrode positive, work negativeElectrode positive, work negative

AC/DC RectifiersAC/DC Rectifiers

TRANSFORMERTRANSFORMERThe transformer in a power supply is a step-down The transformer in a power supply is a step-down transformer that takes high-voltage, low-amperage transformer that takes high-voltage, low-amperage AC input supplied from power companies and AC input supplied from power companies and changes it to low-voltage, high-amperage AC welding changes it to low-voltage, high-amperage AC welding current.current.

For example, your input power may be 230 volts on a For example, your input power may be 230 volts on a 50-amp branch circuit. This voltage is much too high 50-amp branch circuit. This voltage is much too high and the amperage is much too low for welding and the amperage is much too low for welding applications. applications.

The transformer takes this condition and reverses it to The transformer takes this condition and reverses it to a much lower voltage, in the range of 13-45 volts a much lower voltage, in the range of 13-45 volts (most applications 15-35 volts) and increases the (most applications 15-35 volts) and increases the amperage to a much higher level appropriate for amperage to a much higher level appropriate for welding. welding.

RECTIFIER RECTIFIER In power supplies that deliver DC and/or AC and DC current to In power supplies that deliver DC and/or AC and DC current to the arc, there needs to be a device that changes this now low-the arc, there needs to be a device that changes this now low-voltage, high-amperage AC into DC.voltage, high-amperage AC into DC.This device is called a This device is called a rectifierrectifier. A rectifier converts AC to DC. . A rectifier converts AC to DC. They are very efficient and very reliable. They are very efficient and very reliable.A rectifier is a device that allows current to flow in only one A rectifier is a device that allows current to flow in only one direction.direction.If we remember the path that alternating current takes, it takes If we remember the path that alternating current takes, it takes one of a sine wave path. This represents one cycle in which one of a sine wave path. This represents one cycle in which current flows in one direction for ½ of the cycle, stops at the current flows in one direction for ½ of the cycle, stops at the zero line, and reverses it’s direction of flow for the other ½ zero line, and reverses it’s direction of flow for the other ½ cycle. This cycle repeats itself over and over again at a cycle. This cycle repeats itself over and over again at a frequency of 60 Hz or 60 times a second in the United States.frequency of 60 Hz or 60 times a second in the United States.A rectifier does not allow current to reverse itself. It only A rectifier does not allow current to reverse itself. It only allows current to flow in one direction. In essence, it directs allows current to flow in one direction. In essence, it directs current in the same direction rather that allowing it to change current in the same direction rather that allowing it to change direction. This is called direct current of DC. The direction of direction. This is called direct current of DC. The direction of current flow determines whether the polarity is DC+ or DC-.current flow determines whether the polarity is DC+ or DC-.

DUTY CYCLEDUTY CYCLEThe The duty cycleduty cycle of a power source is the of a power source is the percentage of a ten-minute period that it percentage of a ten-minute period that it operates at its rated output current setting.operates at its rated output current setting.

If a power source is rated at 300 amps at a 60% If a power source is rated at 300 amps at a 60% duty cycle, it means that the machine can be duty cycle, it means that the machine can be operated safely at 300 amps welding current for operated safely at 300 amps welding current for 6 out of every 10 minutes. 6 out of every 10 minutes.

If this duty cycle is reduced in actual operation, If this duty cycle is reduced in actual operation, the maximum permissible current is increased. the maximum permissible current is increased. Thus, at a 35% duty cycle, this same 300 amp Thus, at a 35% duty cycle, this same 300 amp power source could be operated at 375 amps power source could be operated at 375 amps

Direct Current Electrode NegativeDirect Current Electrode Negative (Straight)(Straight)

A rectifier allows current to flow in one direction only.A rectifier allows current to flow in one direction only.The direction of the current flow determines the DC The direction of the current flow determines the DC polarity.polarity.DC- or direct current electrode negative is the DC- or direct current electrode negative is the arrangement of direct current arc welding arrangement of direct current arc welding cables/leads in which the electrode is the negative cables/leads in which the electrode is the negative pole and the workpiece is the positive pole of the pole and the workpiece is the positive pole of the welding arc. welding arc. When using DC- polarity, the majority of the heat is When using DC- polarity, the majority of the heat is directed at the electrode. directed at the electrode. The electrodes designed for DC- polarity produce The electrodes designed for DC- polarity produce weld deposits with shallow penetration. Primary weld deposits with shallow penetration. Primary applications are fast travel speeds on sheet metal.applications are fast travel speeds on sheet metal.

Direct Current Electrode Direct Current Electrode PositivePositive (Reverse) (Reverse)

DC+ or direct current electrode positive is the DC+ or direct current electrode positive is the opposite of DC- or direct current electrode opposite of DC- or direct current electrode negative. negative. In this case, the electrode is the positive pole and In this case, the electrode is the positive pole and the workpiece is the negative pole.the workpiece is the negative pole.When using DC+ polarity, the majority of the heat When using DC+ polarity, the majority of the heat is directed at the work piece. is directed at the work piece. The electrodes designed for DC+ polarity produce The electrodes designed for DC+ polarity produce weld deposits with deep penetration. weld deposits with deep penetration. Primary applications are for pipe welding, general Primary applications are for pipe welding, general purpose and maintenance welding, deep purpose and maintenance welding, deep penetration applications, and on base material with penetration applications, and on base material with surface contaminants. surface contaminants.

STRAIGHT POLARITY DC-—ELECTRODE IS NEGATIVE; WORK IS POSITIVE

REVERSE POLARITY DC+ —ELECTRODE IS POSITIVE; WORK IS NEGATIVE

Effect of Polarity on WeldsEffect of Polarity on Welds

Alternating CurrentAlternating CurrentAlternating current is a current that reverses Alternating current is a current that reverses regularly in recurring intervals of time 1/120th regularly in recurring intervals of time 1/120th (60Hz) of a second..(60Hz) of a second..AC is the type of power used in the United States AC is the type of power used in the United States as the standard for input power to run any as the standard for input power to run any electrical equipment or apparatus. It has electrical equipment or apparatus. It has alternating positive and negative values. In other alternating positive and negative values. In other words, it switches from DC+ to DC-, and it words, it switches from DC+ to DC-, and it switches back and forth very rapidly.switches back and forth very rapidly.An AC sine wave and the frequency of current flow An AC sine wave and the frequency of current flow through one sine wave is 60 Hz or 60 times a through one sine wave is 60 Hz or 60 times a second in the U.S. second in the U.S.

Comparison of Penetration Comparison of Penetration ContoursContours

EquipmentEquipmentElectrode holder—holds the rodsElectrode holder—holds the rods

Ground clampGround clamp

Amp Adjustment--sets the heat to adjust the Amp Adjustment--sets the heat to adjust the penetration. penetration. – Greater the heat, the more penetrationGreater the heat, the more penetration– Usually 110-125 ampsUsually 110-125 amps

Helmet--Number 10 lens—Eye protectionHelmet--Number 10 lens—Eye protection– Flip down or automaticFlip down or automatic

Leather GlovesLeather Gloves

Chipping Hammer--remove the slagChipping Hammer--remove the slag

Wire Brush--Cleans the metalWire Brush--Cleans the metal

LENS NUMBERSLENS NUMBERS

Filter plates come in varying shades.Filter plates come in varying shades.

The shade required depends on the maximum The shade required depends on the maximum amount of amperage to be used.amount of amperage to be used.

The recommended shade number for SMAW is 10 The recommended shade number for SMAW is 10 or 11. The lowest shade number recommended is or 11. The lowest shade number recommended is a shade 7. a shade 7.

To determine the correct shade to use, start with To determine the correct shade to use, start with the darkest shade number. If it is difficult to see the darkest shade number. If it is difficult to see the arc, reduce the shade number by one and so the arc, reduce the shade number by one and so on until the appropriate shade is found to provide on until the appropriate shade is found to provide both shielding and visibility of the welding arc.both shielding and visibility of the welding arc.

Electrode Holders/ Chipping Electrode Holders/ Chipping HammerHammer

Welding PositionsWelding PositionsSit or Stand in a relax positionSit or Stand in a relax positionWeld with both handWeld with both handMove across your body.Move across your body.

Right handed person—Left to right.Right handed person—Left to right.

Lean electrode to the right a little bitLean electrode to the right a little bitStart Arc byStart Arc by

TappingTappingScratching.Scratching.

Move electrode either in circles or half moonMove electrode either in circles or half moon

Adjusting the CurrentAdjusting the Current

Heat is adjusted by:Heat is adjusted by:

Thickness of metalThickness of metal

Size of ElectrodeSize of Electrode

Speed of TravelSpeed of Travel

Position of weldPosition of weld

Bead should have deep and even Bead should have deep and even penetration.penetration.

Molten PuddleMolten Puddle

When welding—watch your bead, not ahead When welding—watch your bead, not ahead of the arc.of the arc.

Molten Puddle should tell you:Molten Puddle should tell you:1—Width of bead1—Width of bead

2—Depth of penetration2—Depth of penetration

3—Height of bead3—Height of bead

FluxFlux

Used Around the ElectrodeUsed Around the Electrode

Purposes:Purposes:Forms a gaseous shieldForms a gaseous shield

Gathers impuritiesGathers impurities

Keep weld from cooling to fastKeep weld from cooling to fast

Stabilizers and directs the arc. Stabilizers and directs the arc.

Wire Welding—this is the argon/carbon Wire Welding—this is the argon/carbon dioxide gasdioxide gas

ELECTRODE HOLDERELECTRODE HOLDERElectrode holdersElectrode holders are also rated at a given amperage and are also rated at a given amperage and duty cycle similar to power supplies. duty cycle similar to power supplies. The EH 200, EH 300, and EH 400. Each are rated at 200 The EH 200, EH 300, and EH 400. Each are rated at 200 amps, 300 amps, and 400 amps respectively.amps, 300 amps, and 400 amps respectively.The primary function of the electrode holder is to hold the The primary function of the electrode holder is to hold the electrode and to provide electrical contact of the electrode to electrode and to provide electrical contact of the electrode to the work piece while insulating the operator and the jaws the work piece while insulating the operator and the jaws from the power supply and from the work piece. from the power supply and from the work piece. Copper jaws provide the best electrical contact. Copper jaws provide the best electrical contact. The large insulated handle is designed for operator comfort.The large insulated handle is designed for operator comfort.Insulated jaws prevent accidental grounding. Jaws open Insulated jaws prevent accidental grounding. Jaws open wide for quick release of electrode stubs.wide for quick release of electrode stubs.The positive grip handle remains cool after steady welding at The positive grip handle remains cool after steady welding at rated current and is impact resistant for long life. rated current and is impact resistant for long life.

WORK CLAMPSWORK CLAMPSWork clampsWork clamps are also rated at a given amperage are also rated at a given amperage and duty cycle. The GC 300 and GC 500 are and duty cycle. The GC 300 and GC 500 are rated at 300 amps and 500 amps respectively.rated at 300 amps and 500 amps respectively.The work clamp completes the electrical circuit The work clamp completes the electrical circuit from the electrode as it strikes the arc either to or from the electrode as it strikes the arc either to or from the power supply. This depends upon from the power supply. This depends upon welding polarity.welding polarity.A heavy spring tightly clamps the jaws to promote A heavy spring tightly clamps the jaws to promote positive electrical contact with the work piece. positive electrical contact with the work piece. Work clamps provide for quick connection to the Work clamps provide for quick connection to the work piece. They have easy operation. Just work piece. They have easy operation. Just squeeze, slip the jaws over the work and let go. squeeze, slip the jaws over the work and let go. The jaws open to a full 2 ½” (63mm).The jaws open to a full 2 ½” (63mm).

CABLESCABLESThe ground cable from the power source to the The ground cable from the power source to the electrode carries current to the electrode and electrode carries current to the electrode and from the arc to the workpiece and back to the from the arc to the workpiece and back to the power source. These conductors are very power source. These conductors are very important to the efficiency of welding as well as important to the efficiency of welding as well as the arc characteristics or vice-versa depending the arc characteristics or vice-versa depending upon welding polarity. upon welding polarity. Cables must also be the proper size to deliver the Cables must also be the proper size to deliver the appropriate amount of current to the welding arc. appropriate amount of current to the welding arc. Sizing of the cable is also dependent upon the Sizing of the cable is also dependent upon the length of cable being used. length of cable being used. The conductors in the welding cable are made up The conductors in the welding cable are made up of strands of copper or aluminum. The cables are of strands of copper or aluminum. The cables are wrapped in a paper wrapping. Next, rubber wrapped in a paper wrapping. Next, rubber insulates and covers the jacket wrapping. The insulates and covers the jacket wrapping. The paper wrapping is for cable flexibility.paper wrapping is for cable flexibility.

ElectrodeElectrodeCarries Current to the MetalCarries Current to the MetalSmall end goes into electrode holder. Small end goes into electrode holder. Identification of Electrode, Example 6013Identification of Electrode, Example 6013

A.A. 11stst 2 numbers (60) strength in 10,000 psi---60,000 psi 2 numbers (60) strength in 10,000 psi---60,000 psiB.B. 33rdrd number (1) Welding Position number (1) Welding Position

1—All position-flat, horizontal, vertical, overhead.1—All position-flat, horizontal, vertical, overhead.2—Flat & horizontal2—Flat & horizontal3—Flat3—Flat

C.C. Last two number—chemical makeup of the flux, that Last two number—chemical makeup of the flux, that determines polarity, AC or DCdetermines polarity, AC or DC

10—DC Reverse10—DC Reverse 11—AC/DC 11—AC/DC ReverseReverse

12—DC Straight12—DC Straight 13—AC/DC Straight13—AC/DC Straight14—DC either polarity14—DC either polarity 15—Low Hydrogen15—Low Hydrogen16—AC/DC Reverse. 16—AC/DC Reverse.

SMAW - AWS ClassificationSMAW - AWS Classification The The American Welding SocietyAmerican Welding Society or or AWSAWS sets guidelines sets guidelines for SMAW electrodes with which manufacturers have to for SMAW electrodes with which manufacturers have to comply. comply. These guidelines include chemistry and mechanical These guidelines include chemistry and mechanical properties, and usability tests.properties, and usability tests.Each letter and digit stands for something very specific.Each letter and digit stands for something very specific.The E stands for electrode. AWS defines an electrode The E stands for electrode. AWS defines an electrode as the current carrying device, not necessarily the as the current carrying device, not necessarily the consumable that becomes the weldment. In the case of consumable that becomes the weldment. In the case of SMAW, the electrode core is consumed as well as any SMAW, the electrode core is consumed as well as any metallic elements in the coating to become the weld metallic elements in the coating to become the weld deposit. deposit. The 70 stands for minimum tensile strength in 10,000 The 70 stands for minimum tensile strength in 10,000 psi. The weld deposit made by this SMAW electrode psi. The weld deposit made by this SMAW electrode must consistently meet a minimum tensile strength must consistently meet a minimum tensile strength requirement of 70,000 pounds per square inch (psi).requirement of 70,000 pounds per square inch (psi).

SMAW - AWS ClassificationSMAW - AWS Classification

The next digit is either a 1 or a 2 and indicates The next digit is either a 1 or a 2 and indicates welding position. welding position. A “1” indicates that the electrode is an all A “1” indicates that the electrode is an all position electrode-- (flat, horizontal, vertical up, position electrode-- (flat, horizontal, vertical up, vertical down, and overhead). vertical down, and overhead). While the 2 stands for welds that can only be While the 2 stands for welds that can only be made in the flat/horizontal position.made in the flat/horizontal position.The 3rd and 4th digit combined indicates the The 3rd and 4th digit combined indicates the type of current the electrode operates on and type of current the electrode operates on and the type of coating. the type of coating.

ELECTRODE ANGLEELECTRODE ANGLEElectrode angle can also affect the weld bead profile. Electrode angle can also affect the weld bead profile. When welding a fillet weld, the electrode should be held in When welding a fillet weld, the electrode should be held in the weld joint at approximately a 45the weld joint at approximately a 45 angle from the angle from the horizontal base plate. horizontal base plate. The travel angle will be a drag angle of approximately 15The travel angle will be a drag angle of approximately 15--2020. The electrode is then dragged down the weld joint at . The electrode is then dragged down the weld joint at the appropriate travel speed. the appropriate travel speed. Travel speed is determined by the size of the electrode Travel speed is determined by the size of the electrode being used, the type of electrode, the welding amperage and being used, the type of electrode, the welding amperage and the desired weld bead size and shape. the desired weld bead size and shape. If the electrode angle is too severe and exceeds the If the electrode angle is too severe and exceeds the recommended 45recommended 45, the weld will favor the horizontal plate , the weld will favor the horizontal plate and inadequate fusion can take place, and perhaps burn and inadequate fusion can take place, and perhaps burn through on the bottom plate. The opposite effect can occur through on the bottom plate. The opposite effect can occur for too small of an electrode angle of the electrode in the for too small of an electrode angle of the electrode in the weld joint.weld joint.

STARTING THE ARCSTARTING THE ARC

When starting the arc, strike the electrode When starting the arc, strike the electrode like a match on the work surface by gently like a match on the work surface by gently and quickly moving it along the weld metal. and quickly moving it along the weld metal.

Next, withdraw the electrode to form an arc Next, withdraw the electrode to form an arc length from the work piece of approximately length from the work piece of approximately 1/8”.1/8”.

Reduce the arc length to the approximate Reduce the arc length to the approximate length required to produce the desired length required to produce the desired weld. weld.

ARC LENGTHARC LENGTHArc length is arc voltageArc length is arc voltage. . As the arc length is shortened, the arc voltage is As the arc length is shortened, the arc voltage is lowered. If the arc length is too close to the work lowered. If the arc length is too close to the work piece, the arc will go out or create a dead short. In piece, the arc will go out or create a dead short. In this situation, the voltage drops to 0 and the this situation, the voltage drops to 0 and the amperage rises significantly. This may cause the amperage rises significantly. This may cause the coating on the electrode to break down or even coating on the electrode to break down or even catch on fire if it has an organic coating.catch on fire if it has an organic coating.Arc length is dependent upon the type of electrode Arc length is dependent upon the type of electrode used. Arc length can vary in height from just a drag used. Arc length can vary in height from just a drag to 3/16” distance from the work piece. to 3/16” distance from the work piece. Too long of an arc length will cause the arc to go Too long of an arc length will cause the arc to go out. This situation is called a “pop out”. out. This situation is called a “pop out”.

DETERMING THE AMPERAGEDETERMING THE AMPERAGE

When determining electrode amperages, be sure When determining electrode amperages, be sure to consider:to consider:Position of the weld.Position of the weld.Thickness of the weld metal.Thickness of the weld metal.The type of joint being fabricated.The type of joint being fabricated.Diameter of core wire will be another variable to Diameter of core wire will be another variable to consider - when determining electrode consider - when determining electrode amperages.amperages.The polarity will determine the actual amperage The polarity will determine the actual amperage setting. setting.

Causes of DifficultiesCauses of Difficulties

Welder or metal is improper groundedWelder or metal is improper grounded

Improver electrode contactImprover electrode contactElectrode is placed to high in electrode holderElectrode is placed to high in electrode holder

Flux is Chipped on end.Flux is Chipped on end.Burn end offBurn end off

Wrong AmpsWrong AmpsHeat seating is too high or lowHeat seating is too high or low

Adjust.Adjust.