Chapter 13 Layout and Fabrication of Sheet Metal …

1 Chapter 13. Layout and Fabrication of Sheet Metal and Fiberglass duct Topics Tools and Equipment Sheet Metal Development Joining and Installing Sheet Metal duct Sheet Metal duct Systems Fiberglass duct Systems Safety To hear audio, click on the box. Overview As a Seabee, you will use many pre-fabricated ducts and fittings. However, not all situations call for the use off the shelf parts; therefore, you will be called upon to assess the needs of the job and fabricate the appropriate parts to complete the job.

2 This Chapter introduces you to basic Sheet Metal and fiberglass ductwork Fabrication . You will be introduced to the tools needed to work the Sheet Metal ; some of the methods of measuring, marking, cutting; and the correct methods to form parallel, radial, and triangular Sheet Metal shapes. These techniques are not limited to ductwork, so the processes you learn here can be applied to roofing, flashing, and exterior building siding, to name a few. Remember to keep safety as the main focal point on any jobsite.

3 Objectives When you have completed this Chapter , you will be able to do the following: 1. Describe the tools and equipment associated with Fabrication . 2. Describe procedures utilized in Sheet Metal development. 3. Identify the procedures associated with joining and installing Sheet Metal duct . 4. Identify the different types of Sheet Metal duct systems. 5. Identify the different types of fiberglass duct systems. 6. State the safety regulations associated with Sheet Metal and fiberglass duct systems.

4 Prerequisites None NAVEDTRA 14250A 13-1. This course map shows all of the chapters in Steelworker Basic. The suggested training order begins at the bottom and proceeds up. Skill levels increase as you advance on the course map. Introduction to Reinforcing Steel Introduction to Structural Steel S. Pre-Engineered Structures: T. Buildings, K-Spans, Towers and Antennas E. E. Rigging L. Wire rope W. O. Fiber Line R. Layout and Fabrication of Sheet Metal and Fiberglass duct K. E. Welding Quality Control R.

5 Flux Cored Arc Welding-FCAW. B. Gas- Metal Arc Welding-GMAW A. S. Gas-Tungsten Arc Welding-GTAW. I. Shielded Metal Arc Welding-SMAW C. Plasma Arc Cutting Operations Soldering, Brazing, Braze Welding, Wearfacing Gas Welding Gas Cutting Introduction to Welding Basic Heat Treatment Introduction to Types and Identification of Metal NAVEDTRA 14250A 13-2. Features of this Manual This manual has several features which make it easy to use online. Figure and table numbers in the text are italicized. The figure or table is either next to or below the text that refers to it.

6 The first time a glossary term appears in the text, it is bold and italicized. When your cursor crosses over that word or phrase, a popup box displays with the appropriate definition. Audio and video clips are included in the text, with an italicized instruction telling you where to click to activate it. Review questions that apply to a section are listed under the Test Your Knowledge banner at the end of the section. Select the answer you choose. If the answer is correct, you will be taken to the next section heading.

7 If the answer is incorrect, you will be taken to the area in the Chapter where the information is for review. When you have completed your review, select anywhere in that area to return to the review question. Try to answer the question again. Review questions are included at the end of this Chapter . Select the answer you choose. If the answer is correct, you will be taken to the next question. If the answer is incorrect, you will be taken to the area in the Chapter where the information is for review.

8 When you have completed your review, select anywhere in that area to return to the review question. Try to answer the question again. NAVEDTRA 14250A 13-3. TOOLS and EQUIPMENT. Numerous types of Layout tools, cutting tools, and forming equipment are used when working with Sheet Metal . This section will describe the uses of the Layout and cutting tools and the operation of the forming equipment. Layout Tools The Layout of Metal is the procedure of measuring and marking material for cutting, drilling, or welding.

9 Accuracy is essential in Layout work. Using incorrect measurements results in a part being fabricated that does not fit the overall job. This is a waste of time and material. In most cases, you should use shop drawings, sketches, and blueprints to obtain the measurements required to fabricate the job being laid out. Your ability to read and work from blueprints and sketches is vital in Layout work. For more information on blueprints, go to Blueprint Reading and Sketching, NAVEDTRA 14040. Layout tools are used for drawing Fabrication jobs on Metal .

10 Some of the more common Layout tools are scriber, flat steel square, combination square, protractor, prick punch, dividers, trammel points, and circumference ruler. Scriber Lines are drawn on Sheet Metal with a scribe or scratch awl, coupled with a steel scale or a straightedge. To obtain the best results in scribing, first cover the area to be scribed in a very thin layer of Layout dye, then hold the scale or straightedge firmly in place and set the point of the scriber as close to the edge of the scale as possible by angling the top of the scriber outward.