Module Five (29105-15) Base Metal Preparation
Introduces the trainees to the methods and procedures related to preparing base metal for welding. Trainees will learn safety procedures, welding joint preparation, specifications, identification of physical characteristics, mechanical properties, and cleaning techniques related to common base metals.
Objectives
Learning Objective 1
• Identify safety practices related to preparing base metals and describe basic cleaning procedures.
a. Identify safety practices related to preparing base metals.
b. Describe the basic properties and types of carbon and stainless steel.
c. Describe basic metal cleaning procedures and concerns.
Learning Objective 2
• Identify and describe basic weld joint design and types of welds.
a. Identify and describe the loads that are routinely placed on weld joints.
b. Identify and describe the various types of weld joints.
c. Describe a welding procedure specification (WPS) and the information it provides.
Learning Objective 3
• Describe how to prepare joints for welding.
a. Describe how to mechanically prepare joints for welding.
b. Describe how to thermally prepare joints for welding.
Performance Tasks
Performance Task 1 (Learning Objectives 1 and 3)
• Mechanically or hand grind a bevel on the edge of a 1 ⁄4"- to 3 ⁄4"-thick mild steel plate (6 to 20 mm metric plate) at 22 1 ⁄2 degrees.
Performance Task 2 (Learning Objectives 1 and 3)
• Thermally bevel the edge of a 1 ⁄4"- to 3 ⁄4"-thick mild steel plate (6 to 20 mm metric plate) at 22 1 ⁄2 degrees.
Safety Considerations
This module requires that trainees work with power tools, flammable gases, and an open flame. Safety must be emphasized at all times. Trainees should be carefully observed to ensure that they wear the proper PPE, follow safe practices, and give due respect to unseen hazards related to base metal preparation. Any deficiencies must be corrected to ensure future trainee safety. All practice sessions and performance tasks must be completed under your direct supervision.
Additional Resources
This module presents thorough resources for task training. The following resource material is suggested for further study. 2014 Technical Training Guide. Current Edition. The Lincoln Electric Company, Cleveland, OH 44117-1199 USA. www.lincolnelectric.com
Welding Handbook. Current Edition. Miami, FL: The American Welding Society.
Steel Metallurgy for the Non-Metallurgist. John D. Verhoeven; Prepared under the direction of the ASM International Technical Book Committee. ASM International® Materials Park, OH 44073-0002. www.asminternational.org
American Iron and Steel Institute, 25 Massachusetts Avenue, NW, Suite 800, Washington, DC 20001, USA. www.steel.org.
Association for Iron & Steel Technology, 186 Thorn Hill Road, Warrendale, PA, USA. www.aist.org
“How to Weld: Joint Prep and Beveling” Independent Video, last accessed November 26, 2014. www.youtube.com
There are a number of online resources available for trainees who would like more information on base metal preparation. A search for additional information may be assigned as homework to interested trainees.