Lesson 1Process selection rationale for root, hot, and fill passes on 6 mm 304L butt joint (e.g., GTAW root + pulsed GMAW fill)Gives a clear way to pick methods for root, hot, and fill passes on 6 mm 304L butt joints, weighing GTAW, regular GMAW, and pulsed GMAW for reach, speed, warping, and code or client needs.
Evaluating joint access and position limitsGTAW roots for control and low defect ratesPulsed GMAW for fill and cap productivityBalancing heat input and distortion controlExample procedures for 6 mm butt jointsLesson 2Shielding gas selection and flow rates: pure argon, argon-helium blends, and backing gas needsCovers shield and back gas picks for GTAW and GMAW on 304L, like pure argon, argon-helium mixes, and no-nitrogen back gases, with suggested flows, nozzle sizes, and tricks to stop holes and scaling.
Pure argon for GTAW and GMAW on 304LArgon–helium blends for higher heat inputBacking gas types and oxygen limitsTypical flow rates and nozzle selectionPreventing porosity and sugaring issuesLesson 3Wire and electrode diameters and feed settings for root and fill passes (typical sizes for 6 mm thickness)Spells out usual wire and electrode sizes for 6 mm 304L roots and fills, tying them to feed speed, amps, and build-up rate, and how to tweak for deep reach, bead look, and position work.
Typical GTAW tungsten diameters for 6 mmSolid wire diameters for GMAW on 304LSMAW electrode sizes for plate and pipeWire feed speed versus amperage relationAdjusting size and feed for position weldingLesson 4Recommended parameter ranges: current type, amperage ranges for 6 mm, voltage, travel speed approximationsSets out real-world current, voltage, and travel speed ranges for GTAW, GMAW, SMAW on 6 mm 304L plate, balancing deep reach, bead shape, warp control without missing fusion or burning through.
Current type and polarity choice by processTypical amperage ranges for 6 mm plateVoltage windows for short, spray, and pulseTravel speed targets for root and fill passesAdjusting parameters for position and fit-upLesson 5SMAW (stick) and pulsed TIG/GMAW when applicable: electrode choices and use-casesTells when SMAW, pulsed GTAW, pulsed GMAW work best on 304L, like site jobs, awkward positions, thin-to-thick shifts, with tips on electrode types, sizes, and running ranges.
SMAW electrodes for 304L stainless jointsPulsed GTAW for thin or heat‑sensitive areasPulsed GMAW for out‑of‑position weldsElectrode and wire diameter selectionTypical parameter windows for each optionLesson 6GTAW (TIG) fundamentals: AC vs DC, electrode types (thoriated/lanthanated), electrode preparation and sharpeningGoes over GTAW basics for stainless, pitting AC against DC, tungsten types, tip prep ways, and how electrode shape, current type, shield gas team up for sharp arc, deep reach, smooth bead.
When to use DCEN versus AC on stainlessThoriated versus lanthanated tungsten typesGrinding and tapering tungsten electrodesAvoiding contamination and arc wanderCurrent limits by tungsten size and tip formLesson 7Joint position and rotator use for circumferential welds on ~1 m diameter shellsHandles joint placing and rotators for round welds on about 1 m wide shells, covering setup, lining up, speed control, safety, for steady heat and even bead all round.
Setting up shells on rollers or rotatorsAligning joint gaps and high‑low mismatchSynchronizing rotation and travel speedCable management and operator safetyMaintaining consistent bead profileLesson 8GMAW (MIG/MAG) fundamentals: transfer modes (short-circuit, globular, spray, pulsed), equipment setupIntroduces GMAW basics for stainless, explaining short-circuit, globular, spray, pulsed metal moves, and setting power source, feeder, gun, inductance for steady arcs and low splatter on 304L joins.
Short‑circuit transfer on thin or root passesGlobular transfer limits and drawbacksSpray transfer for flat and horizontal weldsPulsed spray for positional stainless workKey GMAW equipment setup parametersLesson 9Filler metal classifications for 304L stainless: ER308L/ER309L/ER316L selection rules and wire/electrode diametersExplains AWS filler types for 304L stainless, comparing ER308L, ER309L, ER316L, and picking wire/electrode sizes to fit joint plan, position, strength, and rust needs.
Overview of AWS stainless filler designationsWhen to select ER308L for 304L base metalUsing ER309L for dissimilar or butteringUsing ER316L for enhanced corrosion serviceDiameter selection for root and fill passesLesson 10Polarity and power source considerations for GTAW and GMAW with stainlessDetails how power type and polarity hit arc steadiness, reach, bead shape in GTAW and GMAW on stainless, constant current vs voltage acts, and right connections per method.
CC versus CV power source characteristicsGTAW polarity and terminal connectionsGMAW polarity for solid and metal‑cored wireEffects of polarity on penetration patternTroubleshooting arc instability issuesLesson 11Equipment accessories: gas lenses, purging systems, trailing shields, backing strips, and heat sinksShows how extras like gas lenses, purge setups, trailing shields, back strips, heat sinks boost shielding, cut warp, guard root quality on 6 mm 304L plate and round shell joins.
Gas lenses for laminar shielding coverageInternal purging dams and purge monitorsTrailing shields for long stainless beadsBacking bars, strips, and ceramic tilesHeat sinks for distortion and burn‑through
