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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Shielded Metal Arc WeldingShielded Metal Arc Welding
Part IIPart IIA.A. General Information General Information
B.B. PolarityPolarity
C.C. Set UpSet Up
D.D. Striking an ArcStriking an Arc
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Shielded Metal Arc WeldingShielded Metal Arc Welding
An arc welding process with an arc between a coveredAn arc welding process with an arc between a covered
electrode and the weld pool. The process is used withelectrode and the weld pool. The process is used with
shielding from the decomposition of the electrodeshielding from the decomposition of the electrode
covering, covering,
without the without the
application of application of
pressure pressure
and with filler and with filler
metal from metal from
the electrode. the electrode.
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Principles of the SMAW ProcessPrinciples of the SMAW Process
• Electric Arc Between Electrode & Work, Melts the Electric Arc Between Electrode & Work, Melts the Electrode & Fuses the JointElectrode & Fuses the Joint
• Weld Metal & Slag FormWeld Metal & Slag Form• Slag is Slag is
Lighter than the Lighter than the Molten Metal & Molten Metal & Rises to the Rises to the Top Top
• AC or DC AC or DC PolarityPolarity
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
DCEN (Striaght) PolarityDCEN (Striaght) Polarity
• DC -DC -
• Heat Concentrated at Heat Concentrated at ElectrodeElectrode
• Lower PenetrationLower Penetration
• Increased Deposition Increased Deposition Rates Rates
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
DCEN
Direct Current Electrode NegativeDirect Current Electrode Negative
Direct Current Electrode Negative (DCEN):Direct Current Electrode Negative (DCEN):TheThe
arrangement of direct current arc weldingarrangement of direct current arc welding
cables/leads in which the electrode is the cables/leads in which the electrode is the
negative pole and the workpiece is the positive polenegative pole and the workpiece is the positive pole
of the welding arc.of the welding arc.
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
DCEP (Reverse) PolarityDCEP (Reverse) Polarity
• DC +DC +
• Heat Concentrated at Heat Concentrated at WorkpieceWorkpiece
• Forceful, Digging ArcForceful, Digging Arc
• Medium to Deep Medium to Deep PenetrationPenetration
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
DCEP
Direct Current Electrode PositiveDirect Current Electrode Positive
Direct Current Electrode Positive (DCEP):Direct Current Electrode Positive (DCEP): TheThe
arrangement of direct current arc weldingarrangement of direct current arc welding
cables/leads in which the electrode is the cables/leads in which the electrode is the
positive pole and the workpiece is the negative polepositive pole and the workpiece is the negative pole
of the welding arc.of the welding arc.
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
AC PolarityAC Polarity
• Medium PenetrationMedium Penetration
• Medium Travel SpeedsMedium Travel Speeds
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Alternating CurrentAlternating Current
Alternating Current (AC):Alternating Current (AC): A current which reversesA current which reverses
at regularly recurring intervals of time (every 1/100 orat regularly recurring intervals of time (every 1/100 or
1/120 of a second) and which has alternately positive1/120 of a second) and which has alternately positive
and negative values. Modern power systems normallyand negative values. Modern power systems normally
generate a sinusoidal alternating current of either 50generate a sinusoidal alternating current of either 50
or 60 Hertz (Hz). or 60 Hertz (Hz).
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Electrode CableElectrode CableElectrode JawElectrode Jaw
Upper Jaw InsulationUpper Jaw Insulation
Lower JawLower Jaw
Arm InsulationArm Insulation
Cable CouplingCable CouplingGrip HandleGrip HandleConnector PinConnector Pin
Lower Jaw InsulationLower Jaw Insulation
Lincoln Equipment SetupLincoln Equipment Setup
Magnum 300 Amp Electrode HolderMagnum 300 Amp Electrode Holder
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
GC 300GC 300
Tighten Lug To Tighten Lug To Ground ClampGround Clamp
Secure Lug to CableSecure Lug to Cable
SMAW SMAW - Lincoln Equipment Setup- Lincoln Equipment Setup
Magnum 300 Amp Work ClampMagnum 300 Amp Work Clamp
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Lincoln Equipment SetupLincoln Equipment Setup
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Shielded Metal Arc WeldingShielded Metal Arc Welding
• Known as Stick or Manual WeldingKnown as Stick or Manual Welding• Uses CC Power SourceUses CC Power Source• Versatile ProcessVersatile Process• All PolaritiesAll Polarities• Match Electrode Match Electrode
with Power with Power Source, Source, Base Metal, Base Metal, and Joint Designand Joint Design
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
The SMAW Process BasicsThe SMAW Process Basics
Arc
Original Surface Of Base Metal
Reinforcement-Build-up of Weld Metal
Slag
Molten Weld Metal
Protective Gas from Electrode Coating
Electrode Wire(Filler Metal)
Electrode Coating (Flux)
Metal Droplets
Penetration
Arc
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Approximate Electrode Amperage Settings
Fast Freeze Fill Freeze Fast Fill Low HydrogenE6010 - E6011 E6013 - E7014 E7024 - E7028 E7018
Diameter of Current Setting Current Setting Current Setting Current SettingElectrode
Inches(Millimeters) Amperes Amperes Amperes Amperes
3/32 in (2.4 mm) 40 - 90 75 - 105 85 - 155 70 - 140 1/8 in (3.2 mm) 75 - 130 100 - 165 100 - 175 90 - 1855/32 in (4.0 mm) 80 - 160 135 - 225 160 - 270 140 - 2303/16 in (4.8 mm) 110 - 225 185 - 280 220 - 330 210 - 3007/32 in (5.6 mm) 200 - 260 235 - 340 270 - 410 230 - 380 1/4 in (6.4 mm) 220 - 325 260 - 425 315 - 520 290 - 440
Approximate Amperage SettingsApproximate Amperage Settings
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Starting The ArcStarting The Arc
Scratch Start Strike (Tap) Start
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
1. Strike Arc Here
2. Move Electrode to Crown of Crater
3. Resume Travel Forward
Restarting Interrupted BeadRestarting Interrupted Bead
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Bead InitiationBead Initiation
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Bead FormationBead Formation
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Electrode MovementElectrode Movement
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Electrode MovementsElectrode Movements
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Bead TerminationBead Termination
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Copyright Copyright 2004 Lincoln Global Inc. 2004 Lincoln Global Inc.
Sample Beads For Quality WeldingSample Beads For Quality Welding
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