Stainless Steel GTAW/TIG Welding

Course Number: MFG 285
Transcript Title: Stainless Steel GTAW/TIG Weldg
Created: March 25, 2021
Updated: March 25, 2021
Total Credits: 3
Lecture Hours: 0
Lecture / Lab Hours: 60
Lab Hours: 0
Satisfies Cultural Literacy requirement: No
Satisfies General Education requirement: No
Grading options: A-F (default), P-NP, audit
Repeats available for credit: 0

Prerequisites

Corequisites

Course Description

Introduces the use of GTAW/TIG equipment on stainless steel alloys, and the methods and techniques for welding on them. Explores different techniques and special shielding gas requirements for pipe, fillet and butt weldment as well as covering prep of materials, consumables and tungsten. Prerequisites: WLD 195, Co-Requisite: MFG 150. Audit available.

Intended Outcomes

Upon successful completion of this course, students will be able to:

  1. Demonstrate understanding of the unique shielding gas and back purging procedures necessary when welding and manufacturing products from stainless steel.
  2. Identify stainless steel alloy properties and common use as they pertain to manufacturing.
  3. Manufacture DC GTAW stainless steel pipe, fillet and groove weldments.
  4. Correctly clean and prep weldments and tungsten for DC GTAW on stainless steel.
  5. Demonstrate understanding of DC GTAW machine operation, setup and assembly of torch parts.
  6. Manufacture a basic stainless steel pressure vessel.

Outcome Assessment Strategies

Outcomes are assessed through a mixture of hands on and written assessments.  Priority is given to hands-on proficiency based assessment in an environment that rewards demonstration of skill needed for success in industry.

  • Lecture and in booth coaching and direct instruction.
  • Direct instruction in full class demonstration of skills.
  • Written exams.
  • Student proficiency through demonstration of learned strategies and skills in industry standard environment.
  • Mock AWS Testing procedure (destructive testing) or mock local industry supported on-site testing procedures.
  • Job readiness based on performance. 

Texts and Materials

Resources are available openly on the web, but largely the curriculum adaptation needs to be done based on the instructors existing skill set.  Since there are many ways to teach the content, the “teach what you know, and teach well what you do” is very appropriate for courses like this.

The following books are recommended:
  • Welding Skills, 5th Edition, B.J. Moniz
  • Welding Skills Workbook, 5th Edition, Jonathan F. Gosse
Some Suggested resources:
  • AWS Structural Code Book 2020
  • Aeorspacewelding.com
  • Thefabricator.com
  • Aws.org
  • Millerwelds.com
  • Lincolnelectric.com

Course Activities and Design

The determination of teaching strategies used in the delivery of outcomes is generally left to the discretion of the instructor. Here are some strategies that you might consider when designing your course: lecture, small group/forum discussion, flipped classroom, dyads, oral presentation, role play, simulation scenarios, group projects, service learning projects, hands-on lab, peer review/workshops, cooperative learning (jigsaw, fishbowl), inquiry based instruction, differentiated instruction (learning centers), graphic organizers, etc.

Course Content (Themes, Concepts, Issues and Skills)

Outcome #1: Demonstrate understanding of the unique shielding gas and back purging procedures necessary when welding and manufacturing products from stainless steel.
  • Identify different types of shielding gas and their application in welding processes and what gasses are used in GTAW welding of stainless steel alloys.
  • Understand the use and necessity of back purging equipment in GTAW welding of stainless steel alloys.
  • Demonstrate GTAW shielding gas techniques to minimize carbon contamination / corrosion / loss of austenitic properties in stainless steel.
  • Demonstrate GTAW back purging to prevent “sugaring” oxidation on the back of stainless steel joints and pipe.
Outcome #2: Identify stainless steel alloy properties and common use as they pertain to manufacturing.
  • Identify properties of 304 Stainless steel alloy, and it's uses in the manufacturing industry. Know the differences between 304SS from 308 and 316.
  • Identify properties of 308 stainless steel alloy, and it's uses in the manufacturing industry. Know the differences between 308SS from 304 and 316.
  • Identify properties of 316 stainless steel alloy and it's uses in the manufacturing industry. Know the difference between 316SS from 304 and 316.
Outcome #3: Manufacture DC GTAW stainless steel pipe, fillet and groove weldments.
  • Perform pipe, butt, and fillet welds on aluminum of varying thicknesses using GTAW welder in lab.
  • Perform 1G and 2G welds including correct prep of materials.
  • Knowledge of necessary amperage adjustments to ensure full penetration of welds with a blind back side.
Outcome #4: Correctly clean and prep weldments and tungsten for DC GTAW on stainless steel.
  • Clean and prepare materials for welding using chemical cleaning agents appropriate for stainless steel.
  • Clean and prepare materials for welding using machine cleaning processes and procedures appropriate for stainless steel.
  • Post clean materials using chemical agents or electrochemical process as done in industry applications.
  • Know appropriate chemical MSDS and first aid.
Outcome #5: Demonstrate understanding of DC GTAW machine operation, setup and assembly of torch parts.
  • Identify the correct tungsten types for use in DC GTAW and Stainless Steel welding.
  • Identify the correct gas lens size and flow specific to DC GTAW welding on stainless steel.
  • Prepare and assemble torch for DC GTAW welding.
  • Identify parts used specifically for DC GTAW Welding.
  • Identify correct amperage for different thicknesses and alloys of material.
  • Setup DC GTAW equipment for welding stainless steel, including correct pulse settings.
Outcome #6: Manufacture a basic stainless steel pressure vessel.
  • Manufacture a basic stainless steel pressure vessel from two different schedules of pipe and test to specification.
  • Manufacture a basic stainless steel pressure vessel from plate and test to specification.

Department Notes

Safety glasses are required at all times in the welding lab and are provided for students. Students may also purchase their own safety glasses from a local supplier. Long pants and closed toed shoes are required in the welding lab at all times. Appropriate clothing must be worn to work in the lab (no synthetic materials, ect.). Safety requirements are covered prior to work in the lab.