Industrial Processes II INDUSTRIAL PROCESSES II INDEN 3313 Lecture 6 – Case Study Fusion Welding -- Oxyfuel and Electric (Arc) Welding Processes

Industrial Processes II OVERVIEW Case StudyCase Study –Overview and Phases Fusion WeldingFusion Welding –Oxyfuel –Arc –Resistance

Industrial Processes II QUESTIONS TO START ??

Industrial Processes II CASE STUDY Goal to Study the Design and Manufacture of ToolingGoal 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 ( )

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 MeltFusion => Use of Heat to Melt Types (Source of Heat) Types (Source of Heat) –Chemical Reaction (Combustion) OxyFuel Thermit –Electric Arc Consumable Electrode Non-Consumable Electrode

Industrial Processes II FUSION WELDING METHODS Types(cont.) 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 DescriptionBasic Process Description –Use the Heat Produced by the Combustion of Acetylene and Oxygen to Cause Coalescence ParametersParameters –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 ReactionsReactions –1. C 2 H 2 + O 2 -> 2 CO + H 2 + Heat –2. 4 CO + 2 H +3 O 2 -> 4 CO 2 +2 H 2 O + Heat Discussion of FlameDiscussion of Flame –Reducing Neutral Oxidizing 5500 o F2300 o F C2H2C2H2 O2O2

Industrial Processes II OXYFUEL WELDING Common DefectsCommon Defects –Hydrogen Embrittlement –Corrosion (Neutral/Reducing Flame) –Spatter –Inadequate Penetration –Incomplete Fusion AdvantagesAdvantages –Low Cost, Skill Requirements –Portability

Industrial Processes II THERMIT WELDING Basic Process DescriptionBasic Process Description –Use of Heat Produced by Thermite Reaction to Superheat Fe and Use Superheated Fe to Effect Weld ReactionsReactions –1. 3 Fe 3 O Al -> 9 Fe + 4 Al Heat –2. 3 FeO + 2 Al -> 3 Fe + Al Heat –3. Fe Al -> 2 Fe + Al Heat Iron for Weld, Aluminum Oxide Slag (Protects Weld as It Cools)Iron for Weld, Aluminum Oxide Slag (Protects Weld as It Cools)

Industrial Processes II THERMIT WELDING Sources/Causes of DefectsSources/Causes of Defects –Inclusions –Large Grooves Required (Superheat of Base) AdvantagesAdvantages –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 DescriptionBasic Process Description –Creation of an Electrical Potential and Exceeding the Initiation Voltage to Produce an Electrical Arc, the Heat of Which (~55,000 o F) Effects the Weld; the Electrode is Melted by the Arc and Supplies Filler Metal to the Weld ParametersParameters –Distance from Electrode to Work Determines Initiation Voltage, Temperature, Current/Frequency Determines Heat Flux

Industrial Processes II CONSUMABLE ELECTRIC ARC WELDING Two TypesTwo Types –Consumable Electrode –Non-consumable Electrode AdvantagesAdvantages –Automated –High Temperature –High Heat Flux –Shielding from Corrosion

Industrial Processes II CONSUMABLE ELECTRIC ARC WELDING Provision of Non-Corrosive EnvironmentProvision 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 EnvironmentProvision 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 DescriptionBasic 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 ParametersParameters –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 WeldingGas Tungsten- Arc Welding –Gas Shielding Atomic Hydrogen WeldingAtomic Hydrogen Welding –Uses Hydrogen as Shielding Plasma Arc WeldingPlasma Arc Welding –Plasma (60,000 o 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 DescriptionBasic Process Description –Use of Heat Produced by High Velocity Stream of Electrons to Effect Deep Penetration Welds AdvantagesAdvantages –High Penetration ShieldingShielding –Performed in a Vacuum DisadvantagesDisadvantages –Cost, X-Rays Produced

Industrial Processes II LASER BEAM WELDING Basic Process DescriptionBasic Process Description –Use of Heat Produced by High Intensity Beam of Light to Effect Deep Penetration Welds AdvantagesAdvantages –High Penetration ShieldingShielding –Performed in a Vacuum

Industrial Processes II SOLID STATE METHODS Coalescence Through PressureCoalescence Through Pressure Types Types –Resistance Welding –Cold Welding –Ultrasonic Welding –Friction Welding –Explosion Welding –Diffusion Welding

Industrial Processes II RESISTANCE WELDING Basic Process DescriptionBasic Process Description –The Heating of the Base Materials Through Electrical Resistance at Material Interfaces/Discontinuities to Produce Coalescence. SequenceSequence –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 ParametersParameters –Voltage Usually Low Voltage –Current (Amperage) Controls Heat Flux Usually High Current –Time of Current Passage Heat = I 2 * Ω * t –Total Resistance Power = I 2 * Ω –Clamping Time/Pressure –Area of Electrode/Workpiece Contact

Industrial Processes II RESISTANCE WELDING TypesTypes –Spot –Projection –Seam Lap Mash Finish –Butt –Flash –Percussion –Induction

Industrial Processes II RESISTANCE WELDING Spot - Temperature DistributionSpot - Temperature Distribution Amstead, Figure 8.10, p. 168

Industrial Processes II RESISTANCE WELDING SpotSpot Kalpakjian, Figure 28.6b, p. 892

Industrial Processes II RESISTANCE WELDING ProjectionProjection Amstead, Figure 8.11, p. 169

Industrial Processes II RESISTANCE WELDING Seam -- Lap SeamSeam -- Lap Seam Amstead, Figure 8.12, p. 170

Industrial Processes II RESISTANCE WELDING Seam -- Mash SeamSeam -- Mash Seam Amstead, Figure 8.12, p. 170

Industrial Processes II RESISTANCE WELDING Seam -- Finish SeamSeam -- Finish Seam Amstead, Figure 8.12, p. 170

Industrial Processes II RESISTANCE WELDING Butt -- PipeButt -- Pipe Amstead, Figure 8.14a, p. 171

Industrial Processes II RESISTANCE WELDING Butt -- Bar StockButt -- Bar Stock Amstead, Figure 8.14b, p. 171

Industrial Processes II RESISTANCE WELDING Flash (Also Considered Arc Welding)Flash (Also Considered Arc Welding) Kalpakjian, Figure 28.15a, p. 892

Industrial Processes II RESISTANCE WELDING Stud --(Also Considered Arc Welding)Stud --(Also Considered Arc Welding) Kalpakjian, Figure 28.16, p. 898

Industrial Processes II RESISTANCE WELDING PercussionPercussion Modified from Kalpakjian, Figure 28.15, p. 897

Industrial Processes II RESISTANCE WELDING InductionInduction Modified from Kalpakjian, Figure 4.26a,b, p. 147 Part to be Welded

Industrial Processes II QUESTIONS OR CLARIFICATIONS ??? Reminder :