FLUX CORED ARC WELDING FCAW - SS Innershield® Hobart Fabshield FCAW - GS Outershield® Hobart FabCo 1
Principles of the FCAW-SS Process Electric Arc Between Electrode & Work, Melts the Electrode & Fuses the Joint Weld Metal & Slag Form The Slag is Lighter than the Molten Metal & Rises to the Top DC Polarity
Principles of the FCAW-GS Process Electric Arc Between Electrode & Work, Melts the Electrode & Fuses the Joint Weld Metal & Slag Form The Slag is Lighter than the Molten Metal & Rises to the Top DC Polarity
Minor Maintenance & Repair Handle FCAW-SS Gun Assembly Conductor Tube Thread Protector Contact Tip Trigger
FCAW-SS Electrodes
Electrodes Characterized by Long Electrical StickOut (E.S.O.) Typically 3/4” - 3 3/4” with + 1/8” Tolerance Too Long E.S.O. Causes an Unstable Arc, Increased Spatter, and Decreased Penetration Too Short E.S.O. Causes Excessive Arc Length and Premature Melting & Activation of the Core Materials causing Porosity 6
Core Elements Common Core Elements & Their Function Aluminum Deoxidize & Denitrify Calcium Provide Shielding & Form Slag Carbon Increase Hardness & Strength Manganese Deoxidize & Increase Strength Molybdenum Increase Hardness & Strength
Core Elements continued Common Core Elements & Their Function Nickel Improve Hardness, Strength, Toughness, & Corrosion Resistance Potassium Stabilize the Arc & Form Slag Silicon Deoxidize & Form Slag Sodium Stabilize Arc & Form Slag Titanium Deoxidize, Denitrify & Form Slag
Core Element Functions Deep Penetration and High Deposition Rates Even Out of Position Mechanical & Metallurgical Properties Refines the Metal in the Molten Pool with Deoxidizers and Denitrifiers Provides a Slag Coverage to: Protect the Weld Shape the Weld Bead Hold the Weld in Place for Out of Position Welding
FCAW-GS Electrodes
FCAW-GS - Shielding Gases Carbon Dioxide Argon/Carbon Dioxide Mix
CO2 Deeper Penetration Lower Cost Lower Strength Weld Metal Less Susceptible to Gas Marks Lower Cost Less Spray Transfer Less Radiated Heat
AR / CO2 Balances 75/80/85/90 Ar/CO2 Balance Better Mechanical Properties (Charpy, Tensile, Yield) Lower Spatter Better Arc Transfer Lower Smoke Levels Higher Deposition Rates Especially Out of Position Less Penetration
E7 X T- Y AWS Classification Electrode 70,000 psi Min. Tensile Strength Welding Position (0=Flat & Horizontal, 1= All Position) Tubular (Flux Cored Electrode) Usability & Performance Capabilities
E 7X T- Y AWS Classification Electrode 70,000 psi Min. Tensile Strength Welding Position (0=Flat & Horizontal, 1= All Position) Tubular (Flux Cored Electrode) Usability & Performance Capabilities
Metal Core - AWS Classification E 70 C- Y Electrode 70,000 psi Min. Tensile Strength Metal Core Electrode Usability & Performance Capabilities
Flux Cored Arc Welding Summary
Flux Cored Arc Welding-SS A Popular Welding Process in North America Replacement for SMAW for Higher Productive Efficiency Great for Outdoor Welding Covers a Wide Variety of Material Types Good on Dirty Steels and Off Analysis Steels High Deposition Rates 37
The FCAW Process-SS
Flux Cored Arc Welding-GS A Popular Welding Process in North America High Efficiency and Deposition Rates Covers a Wide Variety of Material Types Provides Deep Penetration Requires a Shielding Gas or a Gas Mixture Deposits Low Hydrogen Welds 37
The FCAW Process-GS
Electrode Stickout
Contact Tip Position
Electrical Stick-Out vs Visible Stick-Out
Cross Section of a Fillet Weld
Cross Section of a Groove Weld
Flux Cored Arc Welding Definitions
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).
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. DCEN
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. DCEP
Constant Voltage Power Source Constant Voltage (CV) Power Source: An arc welding power source with a volt-ampere relationship yielding a large welding current change from a small arc voltage change. 4
Constant Current Power Source Constant Current (CC) Power Source: An arc welding power source with a volt-ampere relationship yielding a small welding current change from a large arc voltage change. Not Recommended for FCAW-SS / FCAW-GS 4