Weld Joints Butt Joint Corner Joint Inside Outside

Weld Joints

Butt Joint

Corner Joint Inside Outside

Edge Joint

T Joint

Lap Joint

Electrode Classification

Electrode #’s Tensile Strength Welding Position Special Characteristics 60 = 60, 000 psi 1 = All Positions 0 = Deep/DC + / Fast Freeze 70 = 70, 000 psi 2 = Flat/Horizontal 1 = Deep/AC/DC + / Fast Freeze 80 = 80, 000 psi 3 = Flat Only 3 = Shallow /AC/DC+/DC- 90 = 90, 000 psi 8 = Medium / AC/DC+/Low Hydro

X 1000 lbs sq inch Tensile Strength Special Characteristics • Current Type • Flux Characteristics • Metal Type Electrode • Penetration E 60 1 1 Position

E 60 11 60, 000 psi Special Characteristics • Deep Penetration • Cellulose Potassium flux • Fast Freeze Electrode • AC/DC+ (current) E 60 1 1 All Position

E 60 1 0 60, 000 psi Special Characteristics • Deep Penetration • Cellulose sodium flux • Fast Freeze Electrode • DC+ (current) E 60 1 0 All Position

E 70 1 8 70, 000 psi Special Characteristics • Medium Penetration • Iron Powder Low Hydrogen flux • AC/ DC+ (current) Electrode E 70 1 8 All Position

E 60 1 3 60, 000 psi Special Characteristics • Shallow Penetration • Titania Potassium flux • AC / DC+ / DC - (current) Electrode E 60 1 3 All Position

Electrode #’s Quiz Slide E Electrode 80 80, 000 psi tensile strength 2 Flat/Horizontal Position 1 Deep Penetration Fast Freeze AC/DC + Tensile Strength Welding Position Special Characteristics 60 = 60, 000 psi 1 = All Positions 0 = Deep/DC + / Fast Freeze 70 = 70, 000 psi Electrode 80 = 80, 000 psi E 90 = 90, 000 psi 60 Low + Hydrogen Flux 2 = Flat/Horizontal 1 = Deep/AC/DC / Fast Freeze 60, 000 psi tensile Flat Position strength Medium Penetration 3 = Flat Only 3 = Shallow /AC/DC+ 8 = Medium AC/DC / AC/DC+/Low Hydro 3 8

Welding Terminology

Arc Length n n n Distance between the tip of the electrode and the base metal. Also known as Arc Gap. Long Arc = large Gap Short Arc = Small Gap Shorter the Gap = Cooler the Arc Longer the Gap = Hotter the Arc

Shielding Gases n Carbon Dioxide (C 02) n Co 2/Argon Mix (Mixed Gas) 75%/25% n 85%/15% n 90%/10% n

Wire Speed n n Speed in Inches Per Minute (IPM) that the wire spools through lead cable out the nozzle. Changes the Amp in the Circuit (Current)

Wire Stick-out n n Distance the wire protrudes past electrode tip/nozzle Can: Increase spatter (Too long or short) n Burn tip/wire together (create too much resistance) n Be adjusted to get smooth current (Volts/Amps) n

Gun Angle the Gun/Tip is held from the base metal n 1)Base Angle (BA) n 2)Direction of Travel Angle (DOTA)

Forehand/backhand n Forehand: Pushing the puddle n n 80 Degree Push Backhand: Dragging puddle n 80 Degrees DOT.

Porosity Gas Pocket in/on the weld that is a defect in the weld. Causes: n Long arc n Dirty base metal n Shielding Gas Off (needs to be 20 CF) n n n Gas Off To Low of Pressure To High of Pressure (causes Turbulence) Wind/Weather

Fusion n Combining or joining of two materials

Non Ferrous= n Metal that does not contain Iron n Example: Aluminum/Copper, brass, lead, nickel, tin, titanium

Ferrous Metal n Metal containing Iron n Example: mild steel Metal/Stainless, carbon steel/AR plate

Welding Electrical Terms

Electrical Terms n 12. The arc is extinguished every halfcycle as the current passes through zero, usually at the rate of 120 times per second.

Alternating Current n Current (electrons) is traveling in both directions back and forth. Current is changing from positive-Negative n Hertz: sign wave electrical current n

DC Current n DC: Direct Current n Current is traveling in one direction n Polarity: Changing direction current flows n Ground to Electrode or Electrode to ground

DC Polarity n n DC + electrode is Positive and electrons will flow from neg to pos therefore will go from neg Ground to positive electrode. Reverse polarity/DCEP/DC+ DC - Electrode is negative and electrons will flow from Neg to positive therefore go to the positive ground clamp. Straight polarity/DCEN/DC-

Amps n n The measure of Electrical Flow 1) electrons traveling 2) Water running out of a garden hose would be compared to Amps 3) Water Flow/Electrical Flow

Volts n n Measure of Electrical Pressure 1) Force of electrons 2) Compared to your finger over a running garden hose to generate more pressure. 3) water pressure/Electrical pressure

CC n Constant Current n Amps (Current) stays constant (Vary Slightly) and there are change in voltage during welding process. n ? ? What changes Voltage? n Typical processes: SMAW/GTAW

CV Constant Voltage stays constant (Varies slightly) and there are changes in Current (Amps) during welding process. n ? ? What changes Amperage? n Typical processes: GMAW

Weld Pattern/Movement

Out of position Welding

D. There are four positions used when welding: n Overhead

D. There are four positions used when welding: n Horizontal

D. There are four positions used when welding: n Vertical

D. There are four positions used when welding: n n Flat The flat position produces welds that are stronger than in any other position.

Base metal Prep

9. The double V butt joint is excellent for all load conditions and is often used on metal sections over ¾ inch in thickness.

7. The single V butt joint is often used on plate steel 3 /8 inch to ¾ inch in thickness. This joint is strong in loads with tension forces but weak in loads that bend at the weld root. The weld root is the bottom of the weld groove opposite the weld face.

8. The single-bevel butt joint is used on metals from 1/8 inch to ½ inch in thickness and the bevel is 45 degrees.

4. The plug and slot welds are used to join pieces that overlap. The welds are placed in plug or slot holes. These types of welds commonly take the place of rivets in welded structures.