Unit 6: Fasteners

Section 2: Safety, Tools and Equipment, and Shop Practices

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 6–1 (A) Common nails. (B) A finishing nailFigure 6–2 (A) A roofing nail. (B) A masonry 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– 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 6-21 (A) Front view of completed toggle bolt installation (B) Back view of completed toggle bolt installation Photos by Eugene Silberstein

Figure 6-20 Inserting the folded toggle into the hole in the gypsum board Photos by Eugene Silberstein

Figure 6-22 Plastic Toggle Photo by Eugene Silberstein

Figure 6-25 Securing object to the wall 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

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 6-35 A lag shield anchor

Figure 6-36 A powder-actuated fastener systemPhoto by Eugene Silberstein

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