Lesson 1Welding processes for ship repairs: SMAW, GMAW/MIG, FCAW, and submerged arc—process selectionLooks over main joining ways in ship fixes, comparing SMAW, GMAW, FCAW, and SAW for speed, reach, place skill, and quality, guiding pick for usual structure fixes.
SMAW setup and shipyard applicationsGMAW and MIG variants in repairsFCAW self-shielded and gas-shieldedSubmerged arc for panel renewalsProcess selection decision factorsDistortion and heat input controlLesson 2Corrosion repair for bottom shell plating: local renewals, patch plating, and double-skin/trim patch solutionsExplains rust damage in bottom shell plates and guides picking local new parts, patches, and double-skin ways, stressing rules, load ways, water flow, and long rust guard.
Corrosion types in bottom shell regionsCriteria for local plate renewalsDesign of insert and patch platesDouble-skin and trim patch conceptsScantling checks and class approvalCoating, anodes, and sealing detailsLesson 3Use of advanced materials and consumables: higher-strength steels, corrosion-resistant alloys, and consumable selectionLooks at picking and using stronger steels, rust-proof mixes, and joining fillers, focusing on matching power, toughness, rust act, and join ease in usual ship fix cases.
Grades of higher-strength ship steelsCorrosion-resistant alloys in repairsMatching and overmatching consumablesHydrogen-controlled consumable typesStorage and handling of electrodesDissimilar metal joint strategiesLesson 4Cutting and removal: oxy-fuel, plasma, and CNC/high-precision thermal cuttingExplains safe and true taking out of damaged parts using gas-fire, plasma, and CNC heat cut, handling tool set, cut good, heat zones, and cutting bend and re-do.
Selection of cutting process by taskOxy-fuel cutting setup and safetyManual and mechanized plasma cuttingCNC and template-guided cuttingControl of HAZ and edge qualityDistortion control during removalLesson 5Prefabrication and modular panel replacement: templates, edge preparation and tolerancesCovers planning and making ready-made panels, with measure ways, pattern making, edge ready, allowed gaps, and lining to cut ship time and join bend.
Damage survey and panel mappingTemplate methods and digital scanningShop fabrication and fit-up checksEdge preparation and root gapsDimensional tolerances and fairnessLifting, handling, and positioningLesson 6Weld quality control: welders qualification, NDT acceptance criteria, and repair limitsCovers join quality check in ship fix, with joiner skill, plan follow, no-dig tests, okay rules, and fix limits, making sure structure strong and rules met.
Welder qualification and continuityVisual inspection and weld gaugesUltrasonic and radiographic testingMagnetic particle and dye penetrantAcceptance criteria and defect limitsRepair welding and reinspection stepsLesson 7Damage assessment to repair decision framework and scope definitionGives a set way from first damage check to fix choice and range set, mixing rules need, risk, cost, stop time, and long structure work.
Initial inspection and data collectionUse of NDT and thickness measurementsResidual strength and buckling checksTemporary versus permanent repairsRepair scope and work package definitionCoordination with class and ownerLesson 8Welding procedure specifications (WPS), preheat/postheat, PWHT considerations for common ship steelsDescribes making and skill of join plans for ship steels, with warm before and between, after warm, and heat treat choices, minding gas crack, hard limits, and rule papers.
Essential WPS variables and rangesPreheat and interpass temperature controlPostheat for hydrogen diffusionPWHT need, methods, and limitsHardness and microstructure controlWPS qualification and recordsLesson 9Joint design improvements to reduce stress concentrations and extend fatigue lifeFocuses on join shape better to cut stress spots and make tiredness last, covering shape changes, soft joins, back parts, join shapes, and line to best load pass.
Assessment of existing joint detailsNotch effects and stress raisersSmooth transitions and tapersBacking bars and run-on tabsOptimized weld profiles and toesAlignment and fit-up tolerancesLesson 10Fatigue crack repair strategies: stop-holes, full-penetration welds, splice plates, doublers and redesign of detailsDetails tiredness crack ways and fix picks, like stop holes, join take out, full join, splice plates, extra layers, and shape change to better tiredness life and rule follow.
Identification of fatigue-prone detailsCrack sizing and monitoring methodsStop-holes and crack arrest drillingFull-penetration weld repair stepsUse of splice plates and doublersDetail redesign to reduce hotspots
