Section 2: Safety, Tools and Equipment, and Shop Practices Unit 6: Fasteners

Objectives After studying this chapter, you should be able to: Identify common fasteners used with wood Identify common fasteners used on hollow walls Identify common fasteners used with sheet metal Write and explain a typical tapping screw dimension

Objectives (cont’d.) Identify typical machine screw heads Write and explain each part of a machine screw thread dimension Identify and describe fasteners used in masonry applications Describe hanging devices for piping, tubing, and ductwork Describe solderless terminals and screw-on wire connectors

Nails The most popular fastener for securing wood Different styles and types for different uses Common nails Masonry nails Finishing nails Roofing nails Nails are sized by the term “penny”

Nails (cont’d.) Figure 6–2 (A) A roofing nail. (B) A masonry nail Figure 6–1 (A) Common nails. (B) A finishing nail

Staples and Rivets Staples are available in a number of sizes for different applications, such as fastening wire in place Rivets (pin or blind) are used to join two pieces of sheet metal

Staples and Rivets (cont’d.) Figure 6.3 Staples used to fasten wire to wood Figure 6.5 A staple that is clinched outward (used to fasten soft materials together)

Threaded Fasteners Wood screws Tapping screws Fasten many types of materials to wood Generally have a flat, round, or oval head Tapping screws Also known as sheet metal screws Some are self-drilling

Threaded Fasteners (cont’d.) Machine screws or bolts Used in conjunction with nuts, which thread onto the screw Manufactured with different head shapes including round and hex Set screws Can have different heads Typically used to secure pulleys to motor or blower shafts

Threaded Fasteners (cont’d.) Anchors Shield with a screw Hollow wall Toggle bolts Provide a secure anchoring in hollow tiles, building block, plaster over lath, and gypsum board

Figure 6-20 Inserting the folded toggle into the hole in the gypsum board Photos by Eugene Silberstein Figure 6-21 (A) Front view of completed toggle bolt installation (B) Back view of completed toggle bolt installation Photos by Eugene Silberstein

Figure 6-22 Plastic Toggle Photo by Eugene Silberstein Figure 6-26 Self-drilling drywall anchors Photo by Eugene Silberstein Figure 6-27 Installing the self-drilling drywall anchor. Photo by Eugene Silberstein Figure 6-25 Securing object to the wall Photo by Eugene Silberstein

Threaded Fasteners (cont’d.) Threaded rod and steel channel or steel channel and pipe clamps can also be used Figure 6-28 Using threaded rod and angle steel to fabricate a hanger

Concrete Fasteners Figure 6-34 A concrete screw fastener Figure 6-36 A powder-actuated fastener system Photo by Eugene Silberstein Figure 6-35 A lag shield anchor

Other Fasteners Include Cotter pins – Secure pins Pipe hooks – Wire bent to form a “U” to support pipes Pipe straps – Mount pipes to a surface Perforated strap – Strapping material with spaced holes Nylon straps – Secure flexible duct to sheet metal collars

Other Fasteners (cont’d.) Grille clips – Mount supply registers and grilles Solderless terminals – Fasten stranded wire to various terminals or to connect two lengths of stranded wire together Screw-on wire connectors – Connect two or more wires together

Summary Many fasteners are used in the HVAC industry, including nails, screws, staples, anchors, and shields Wire hooks, pipe straps, perforated straps, and threaded rod can be used to mount piping materials, duct sections, and pieces of air conditioning equipment

Summary (cont’d.) Nylon straps can be used to secure flexible duct to sheet metal collars