Introduction to Welding & Non-Destructive Testing

What are the Goals?

At the end of this training course, you will learn to:

• Types of welding process, including oxyacetylene, SMAW, TIG, MIG, and others
• Types of joints and joint design will be introduced, e.g. but, square, grooved, bevel, butt, U, J and T, flush
• Various weld defects and imperfections will be presented including, porosity, solidification cracking, hydrogen cracking, incomplete root fusion or penetration, residual stresses, reheat cracking, lamellar tearing, liquation cracking, slag inclusion and trouble shooting
• Basic metallurgy will be presented and related to welding technology, including the weldabillity of ferrous and nonferrous metals, heat treatment and the significance of the heat affected zone, HAZ
• Welding parameters, including standards, metal transfer, welding currents, shielding gas and electrode selection will be included in the courseWelding engineering drawing including standard welding symbols will be presented
• Mechanical testing and failure of welds will be presented in addition to nondestructive techniques, NDT

Daily Agenda

Day One: Introduction and Weld Joint Design 

• Introduction, welding terminology, codes and standards, welding failure and case studies
• Introduction to quality, meeting requirements, customer satisfaction, quality control, how can quality be achieved?
• Weld joint design, load performance, types of joints, butt joint, square, grooved butt joint, single V, Double V butt Joint, bevel and double bevel butt, U, J and T, flush
• Welding techniques, positional welding, backing, examples, butt welds without backing

Day Two: Welding Processes 

• Welding processes, process options, benefits, problems and applications, oxyacetylene process, fusion welding processes, shielded metal arc welding (SMAW), submerged arc welding, TIG welding, solid wire MIG welding, types of flux/electrodes, metal transfer mode, power source and welding current, arc starting, shielding gas, operating characteristics, applications
• Arc welding electrodes, US standard electrodes, electrode identification, electrode size and currents, common electrode types, extended electrode classification examples, BS classification of electrodes

Day Three: Welding Defects and Imperfections 

• Welding defects, introduction, heat affected zone, HAZ, weld defects and imperfections, porosity, solidification cracking, hydrogen cracking, incomplete root fusion or penetration, residual stresses and cracking, reheat cracking, lamellar tearing, liquation cracking, slag inclusion
• Geometric shape imperfections - types and causes, excess weld metal, undercut, overlap (cold lapping), linear misalignment, incomplete filled groove, trouble shooting

 Day Four: Welding Technical Prints, Symbols and Basic Metallurgy 

• Welding drawings (symbols), introduction, types of projection, welding joints, symbols for welds, parts of the welding symbols, placement of welding symbols, special welds, weld all around, field weld symbols and multiple reference lines
• Basic metallurgy crystalline structure of metals, crystal growth an overall bulk solidification of metals, solid solution, inter-metallic compounds, diffusion, micro-structure of carbon steel, heat treatment of steel, critical cooling rate and mass effect, heat affected zone (HAZ) in Welding, HAZ of carbon and alloy steels, HAZ of stainless steel
• Welding drawings (symbols), introduction, types of projection, welding joints, symbols for welds, parts of the welding symbols, placement of welding symbols, special welds, weld all around, field weld symbols and multiple reference lines
• Basic metallurgy crystalline structure of metals, crystal growth an overall bulk solidification of metals, solid solution, inter-metallic compounds, diffusion, micro-structure of carbon steel, heat treatment of steel, critical cooling rate and mass effect, heat affected zone (HAZ) in Welding, HAZ of carbon and alloy steels, HAZ of stainless steel
• Materials for welded sections, weldability of steel groups, stainless steels, cast irons, aluminium alloys, filler alloys, avoiding weld imperfections

 Day Five: Materials Testing and Non-Destructive Testing (NDT) 

• Materials testing and failure, tensile testing, properties obtained from the tensile test, ductility and fracture in metals, impact testing (Izod and Charpy), transition temperature, hardness tests (Vickers and Rockwell), failure due to fracture, stress concentration, fracture toughness, fatigue failure, destructive testing of welds, bend tests, bead-on plate test, controlled thermal severity (C.T.S.) test, the test and assessment hierarch
• Nondestructive testing (NDT), definition and purpose of non-destructive testing, engineering demands for sounder materials, ensuring the integrity and reliability, maintaining uniform quality level of a product, dye penetrant, magnetic methods, X-ray methods, γ - ray methods, ultrasonic methods eddy current testing, selection of N. D. T. methods, ISO standards for NDT Inspection