Welding Defect Analysis

2-Day Course

Learn how to evaluate parts for welding defects associated with resistance, MIG, and projection welding operations. Students will learn the troubleshooting skills necessary to address weld quality issues and suggest potential counter measures in the automotive manufacturing environment. 


WHO SHOULD ATTEND:

All types of Engineers, Product Designers, Tool and Die Makers, Welding Maintenance and Launch Personnel.


COURSE OUTLINE:

1.0 How a Weld is Made



1.1 Resistance Spot Welding

1.2 Characteristics of the Weld Nugget

1.2.1 Making a Spot Weld
· Single Spot
· Double Spot
· Projection Weld

1.3 Relationship of the Welding Variables

· Single Spot

· Double Spot

· Projection Weld

1.4 The Elementary Welding System


2.0 Weld Schedules, Metals and Other Variables



2.1 Resistance Spot Welding

2.2 Basic Welding Circuit

· Producing Weld Heat

· Spot and Projection Welding Components

· Electrodes and Other Current-Carrying Members

· Pressure System

2.3 Weld Sequence

· Squeeze

· Weld Time

· Hold

2.4 Welding Variables (Single, Double, Projection Welds)

· Weld Circuit Effects on Weld Heat

· Current and Voltage

· Electrode Face Area

· Time

· Weld Loop Impedance

· Electrode Force


3.0 Protective Coatings and Contaminants



3.1 Galvanized Steel

· Hot Dipped

· Electroplate

3.2 Contaminants on the Metal

· Drawing Compound

· Dirt and Scale

· Oils

· Rust

· Sealer

3.3 Composition of Metal (Metallurgy)

· Weld Heat Balance

· Equal Thickness

· Unequal Thickness


4.0 Weld Schedules



4.1 Weld Tables

· Three-ply Weld Schedule


5.0 Weld Quality Defects (Spot and Projection Welds)



5.1 Surface Defects

· Indentation

· Surface Deformation Surface Burning

· Surface Expulsion (Wiskers)

· Cracks

· Blow Holes

5.2 Weld Nugget Defects

· Undersize Nugget

· Low Penetration

· Porosity

· Expulsion

· Misshaped Weld Nugget

· Poor Part Fit-up

· Fixture Related Issues

· Poor Electrode Alignment

5.3 Corrective Action for Eliminating Spot Weld Defects

· Correction of Surface Defects

· Correction of Weld Nugget Defects


6.0 General Maintenance



6.1 Weld Schedules

6.2 Caps

6.3 Water Tubes

3.2 Contaminants on the Metal
6.4 Guns
6.5 Cables

6.6 Fixtures


7.0 Troubleshooting



7.1 Generic Weld Inspection Process

· Destructive Testing

· Non-Desctructive Testing (W & A)

7.2 Troubleshooting Flow Chart

7.3 Welding Sequence Consequences

· Spot and Projection Welding

· MIG Welding

· Laser Welding


8.0 Exercises


Interactive hands on exercises designed to introduce the students to the troubleshooting process:



Exercise 1: Identifying Common Spot Weld defects

Exercise 2: Evaluating Spot Weld Defects on Assemblies

Exercise 3: Identifying Common Projection Weld Defects

Exercise 4: Identfying Common MIG Weld Defects

Exercise 5: Evalauting MIG Weld Defects on Assemblies

Exercise 6: Evaluating Projection Weld Defects on Assemblies

Exercise 7: Rework Methods for Weld Defects