1. 1 Copyright  2004 Lincoln Global Inc. Shielded Metal Arc Welding Part II A.General Information B.Polarity C.Set Up D.Striking an Arc

2. 2 Copyright  2004 Lincoln Global Inc. Shielded Metal Arc Welding An arc welding process with an arc between a covered electrode and the weld pool. The process is used with shielding from the decomposition of the electrode covering, without the application of pressure and with filler metal from the electrode.

3. 3 Copyright  2004 Lincoln Global Inc. Principles of the SMAW Process Electric Arc Between Electrode & Work, Melts the Electrode & Fuses the JointElectric Arc Between Electrode & Work, Melts the Electrode & Fuses the Joint Weld Metal & Slag FormWeld Metal & Slag Form Slag is Lighter than the Molten Metal & Rises to the TopSlag is Lighter than the Molten Metal & Rises to the Top AC or DC PolarityAC or DC Polarity

4. 4 Copyright  2004 Lincoln Global Inc. DCEN (Striaght) Polarity DC -DC - Heat Concentrated at ElectrodeHeat Concentrated at Electrode Lower PenetrationLower Penetration Increased Deposition RatesIncreased Deposition Rates

5. 5 Copyright  2004 Lincoln Global Inc. DCEN Direct Current Electrode Negative Direct Current Electrode Negative (DCEN):The arrangement of direct current arc welding cables/leads in which the electrode is the negative pole and the workpiece is the positive pole of the welding arc.

6. 6 Copyright  2004 Lincoln Global Inc. DCEP (Reverse) Polarity DC +DC + Heat Concentrated at WorkpieceHeat Concentrated at Workpiece Forceful, Digging ArcForceful, Digging Arc Medium to Deep PenetrationMedium to Deep Penetration

7. 7 Copyright  2004 Lincoln Global Inc. DCEP Direct Current Electrode Positive Direct Current Electrode Positive (DCEP): The arrangement of direct current arc welding cables/leads in which the electrode is the positive pole and the workpiece is the negative pole of the welding arc.

8. 8 Copyright  2004 Lincoln Global Inc. AC Polarity Medium PenetrationMedium Penetration Medium Travel SpeedsMedium Travel Speeds

9. 9 Copyright  2004 Lincoln Global Inc. Alternating Current Alternating Current (AC): A current which reverses at regularly recurring intervals of time (every 1/100 or 1/120 of a second) and which has alternately positive and negative values. Modern power systems normally generate a sinusoidal alternating current of either 50 or 60 Hertz (Hz).

10. 10 Copyright  2004 Lincoln Global Inc. On/Off Switch Electrode Lead Work Clamp Work Lead Amperage Dial Electrode Holder Amperage Indicator Polarity Switch Lincoln Equipment Setup Idealarc 250

11. 11 Copyright  2004 Lincoln Global Inc. Electrode Cable Electrode Jaw Upper Jaw Insulation Lower Jaw Arm Insulation Cable Coupling Grip Handle Connector Pin Lower Jaw Insulation Lincoln Equipment Setup Magnum 300 Amp Electrode Holder

12. 12 Copyright  2004 Lincoln Global Inc. GC 300 Tighten Lug To Ground Clamp Secure Lug to Cable SMAW - Lincoln Equipment Setup Magnum 300 Amp Work Clamp

13. 13 Copyright  2004 Lincoln Global Inc. Lincoln Equipment Setup

14. 14 Copyright  2004 Lincoln Global Inc. Shielded 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 with Power Source, Base Metal, and Joint DesignMatch Electrode with Power Source, Base Metal, and Joint Design

15. 15 Copyright  2004 Lincoln Global Inc. The 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

16. 16 Copyright  2004 Lincoln Global Inc. Approximate Amperage Settings

17. 17 Copyright  2004 Lincoln Global Inc. Starting The Arc Scratch StartStrike (Tap) Start

18. 18 Copyright  2004 Lincoln Global Inc. 1. Strike Arc Here 2. Move Electrode to Crown of Crater 3. Resume Travel Forward Restarting Interrupted Bead

19. 19 Copyright  2004 Lincoln Global Inc. Bead Initiation

20. 20 Copyright  2004 Lincoln Global Inc. Bead Formation

21. 21 Copyright  2004 Lincoln Global Inc. Electrode Movement

22. 22 Copyright  2004 Lincoln Global Inc. Electrode Movements

23. 23 Copyright  2004 Lincoln Global Inc. Bead Termination

24. 24 Copyright  2004 Lincoln Global Inc. Sample Beads For Quality Welding