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INDUSTRIAL PROCESSES II INDEN 3313 Lecture 6 – Case Study Fusion Welding -- Oxyfuel and Electric (Arc) Welding Processes Industrial Processes II OVERVIEW • Case Study – Overview and Phases • Fusion Welding – Oxyfuel – Arc – Resistance Industrial Processes II QUESTIONS TO START ?? Industrial Processes II CASE STUDY • Goal to Study the Design and Manufacture of Tooling – Phase I (15%) • Identify Possible Parts for Case Study • Each Student to Identify Three (3) Parts for Case Study – One part => Cast – One Part => Machined – One Part => Other Than Cast/Machined that will require tooling for its Production (Forging Dies, Stamping/Bending Dies, …) • Form/Format on Web – Part (Name, Function, Sketch) • Due Next Thursday – Hard Copy and Electronic Submission (e-mail) Industrial Processes II CASE STUDY – Phase II (15%) – Part Processing Concepts • Following Part Submission (Phase I) Instructor • • • • will select/modify Parts and Assign A processing sequence will be designed for the part and the tooling requirement(s) for its production via this sequence will be determined. Each student will execute this phase for one part concept. Due 2/22/00 Format on Web Industrial Processes II CASE STUDY – Phase III (70%) • Each Student will detail the design and manufacture (parameters, costs, …) of an assigned piece of tooling. For part concepts requiring more than one piece of tooling, one student will be assigned each piece and one report will be developed for each part. – 10% -- Schedule for Project (Due 3/8/00) and Progress/Adherence to Schedule (Due 3/29/00) – 20% -- Completed Draft (Due 4/12) Evaluation of Technical Data and Report Format/Content Completeness (Format on Web IEM Tech. Writing) – 40% -- Final Draft with all Technical Corrections and Presentation of Results to Class. (Slides Due 4/26, Final Report Due 4/28) • Schedule may be modified to accommodate ENGL 3323 Industrial Processes II FUSION WELDING METHODS • Fusion => Use of Heat to Melt • Types (Source of Heat) – Chemical Reaction (Combustion) • OxyFuel • Thermit – Electric Arc • Consumable Electrode • Non-Consumable Electrode Industrial Processes II FUSION WELDING METHODS • Types(cont.) – Beam • Electron Beam • Laser – Electrical Resistance • Note: Text Classifies as Solid State Process -- Nugget is Molten, But Contained Industrial Processes II OXYFUEL WELDING • Basic Process Description – Use the Heat Produced by the Combustion of Acetylene and Oxygen to Cause Coalescence • Parameters – Rate of Combustion • Affects Heat, Not Temperature • Size of (Nozzle) Tip – Maintenance of Non-Corrosive Shield – Operator Skill, Preparation of Parts Industrial Processes II OXYFUEL WELDING • Reactions – 1. – 2. C2H2 + O2 -> 2 CO + H2 + Heat 4 CO + 2 H +3 O2 -> 4 CO2 +2 H2O + Heat • Discussion of Flame O2 5500o F 2300o F C2H2 – Reducing Neutral Industrial Processes II Oxidizing OXYFUEL WELDING • Common Defects – – – – – Hydrogen Embrittlement Corrosion (Neutral/Reducing Flame) Spatter Inadequate Penetration Incomplete Fusion • Advantages – Low Cost, Skill Requirements – Portability Industrial Processes II THERMIT WELDING • Basic Process Description – Use of Heat Produced by Thermite Reaction to Superheat Fe and Use Superheated Fe to Effect Weld • Reactions – 1. 3 Fe3O4 + 8 Al -> 9 Fe + 4 Al203 + Heat – 2. 3 FeO + 2 Al -> 3 Fe + Al203 + Heat – 3. Fe203 + 2 Al -> 2 Fe + Al203 + Heat • Iron for Weld, Aluminum Oxide Slag (Protects Weld as It Cools) Industrial Processes II THERMIT WELDING • Sources/Causes of Defects – Inclusions – Large Grooves Required (Superheat of Base) • Advantages – Large Amounts of Filler Metal Available Quickly Industrial Processes II THERMIT WELDING [Amstead et al, Figure 8.26, p. 186] Industrial Processes II CONSUMABLE ELECTRIC ARC WELDING • Basic Process Description – Creation of an Electrical Potential and Exceeding the Initiation Voltage to Produce an Electrical Arc, the Heat of Which (~55,000o F) Effects the Weld; the Electrode is Melted by the Arc and Supplies Filler Metal to the Weld • Parameters – Distance from Electrode to Work Determines Initiation Voltage, Temperature, Current/Frequency Determines Heat Flux Industrial Processes II CONSUMABLE ELECTRIC ARC WELDING • Two Types – Consumable Electrode – Non-consumable Electrode • Advantages – Automated – High Temperature – High Heat Flux – Shielding from Corrosion Industrial Processes II CONSUMABLE ELECTRIC ARC WELDING • Provision of Non-Corrosive Environment – Shielded Metal Arc Welding (SMAW) • Flux Coated Stick Electrode – Submerged Arc Welding (SAW) • Flux Supplied by Separate Delivery System – Gas Metal Arc Welding (GMAW) • Inert Gas Supplied - Local Inert Atmosphere Around Weld – Flux Cored Arc Welding (FCAW) • Flux Embedded in ‘Hollow’ Electrode (Wire) Industrial Processes II CONSUMABLE ELECTRIC ARC WELDING • Provision of Non-Corrosive Environment – Electro-Gas Welding (EGW) • Inert Gas Supplied – Electroslag Welding (ESW) • Slag Used to Shield • Technically, Arc is Extinguished - Resistance Used To Heat Industrial Processes II SHIELDED METAL ARC WELDING [Kalpakjian, Figure 27.4, p. 862] Industrial Processes II SUBMERGED METAL ARC WELDING [Kalpakjian, Figure 27.7, p. 864] Industrial Processes II GAS METAL ARC WELDING [Kalpakjian, Figure 27.8, p. 865] Industrial Processes II FLUX CORED ARC WELDING [Kalpakjian, Figure 27.10, p. 867] Industrial Processes II ELECTRO-GAS WELDING [Kalpakjian, Figure 27.11, p. 868] Industrial Processes II ELECTROSLAG WELDING [Kalpakjian, Figure 27.12, p. 869] Industrial Processes II NON-CONSUMABLE ELECTRIC ARC WELDING • Basic Process Description – Creation of an Electrical Potential and Exceeding the Initiation Voltage to Produce an Electrical Arc, the Heat of Which (~55,000o F) Effects the Weld; the Electrode is Not Melted by the Arc and a Separate Rod (Optional) Supplies Filler Metal to the Weld • Parameters – Distance from Electrode to Work Determines Initiation Voltage, Temperature, Current/Frequency Determines Heat Flux Industrial Processes II NON-CONSUMABLE ELECTRIC ARC WELDING • Gas Tungsten- Arc Welding – Gas Shielding • Atomic Hydrogen Welding – Uses Hydrogen as Shielding • Plasma Arc Welding – Plasma (60,000o F) – Shielding Gas Used Industrial Processes II Gas Tungsten- Arc Welding • [Kalpakjian, Figure 27.13, p. 872] Industrial Processes II Plasma Arc Welding [Kalpakjian, Figure 27.15, p. 874] Industrial Processes II ELECTRON BEAM WELDING • Basic Process Description – Use of Heat Produced by High Velocity Stream of Electrons to Effect Deep Penetration Welds • Advantages – High Penetration • Shielding – Performed in a Vacuum • Disadvantages – Cost, X-Rays Produced Industrial Processes II LASER BEAM WELDING • Basic Process Description – Use of Heat Produced by High Intensity Beam of Light to Effect Deep Penetration Welds • Advantages – High Penetration • Shielding – Performed in a Vacuum Industrial Processes II SOLID STATE METHODS • Coalescence Through Pressure • Types – – – – – – Resistance Welding Cold Welding Ultrasonic Welding Friction Welding Explosion Welding Diffusion Welding Industrial Processes II RESISTANCE WELDING • Basic Process Description – The Heating of the Base Materials Through Electrical Resistance at Material Interfaces/Discontinuities to Produce Coalescence. • Sequence – Material Surfaces Cleaned and Aligned – Electrodes Used to Clamp Components in Place – Current Passed Through Components (Electrodes Water Cooled), Nugget Melted – Current Turned Off, Coalescence, Unclamped Industrial Processes II RESISTANCE WELDING • Parameters – Voltage • Usually Low Voltage – Current (Amperage) • Controls Heat Flux • Usually High Current – Time of Current Passage • Heat = I2 * Ω * t – Total Resistance • Power = I2 * Ω – Clamping Time/Pressure – Area of Electrode/Workpiece Contact Industrial Processes II RESISTANCE WELDING • Types – Spot – Projection – Seam • Lap • Mash • Finish – – – – Butt Flash Percussion Induction Industrial Processes II RESISTANCE WELDING • Spot - Temperature Distribution Amstead, Figure 8.10, p. 168 Industrial Processes II RESISTANCE WELDING • Spot Kalpakjian, Figure 28.6b, p. 892 Industrial Processes II RESISTANCE WELDING • Projection Amstead, Figure 8.11, p. 169 Industrial Processes II RESISTANCE WELDING • Seam -- Lap Seam Amstead, Figure 8.12, p. 170 Industrial Processes II RESISTANCE WELDING • Seam -- Mash Seam Amstead, Figure 8.12, p. 170 Industrial Processes II RESISTANCE WELDING • Seam -- Finish Seam Amstead, Figure 8.12, p. 170 Industrial Processes II RESISTANCE WELDING • Butt -- Pipe Amstead, Figure 8.14a, p. 171 Industrial Processes II RESISTANCE WELDING • Butt -- Bar Stock Amstead, Figure 8.14b, p. 171 Industrial Processes II RESISTANCE WELDING • Flash (Also Considered Arc Welding) Kalpakjian, Figure 28.15a, p. 892 Industrial Processes II RESISTANCE WELDING • Stud --(Also Considered Arc Welding) Kalpakjian, Figure 28.16, p. 898 Industrial Processes II RESISTANCE WELDING • Percussion Modified from Kalpakjian, Figure 28.15, p. 897 Industrial Processes II RESISTANCE WELDING • Induction Part to be Welded Modified from Kalpakjian, Figure 4.26a,b, p. 147 Industrial Processes II QUESTIONS OR CLARIFICATIONS ??? Reminder : Industrial Processes II