Page 137 - Fundamental of Engineering Design

Drive rivet A drive rivet is a form of blind rivet that has a short mandrel protruding from the head that is
driven in with a hammer to flare out the end inserted in the hole. This is commonly used to
rivet wood panels into place since the hole does not need to be drilled all the way through
the panel, producing an aesthetically pleasing appearance. They can also be used with
plastic, metal, and other materials and require no special setting tool other than a hammer
and possibly a backing block (steel or some other dense material) placed behind the
location of the rivet while hammering it into place. Drive rivets have less clamping force than
most other rivets.
Flush rivet A flush rivet is used primarily on external metal surfaces where good appearance and the
elimination of unnecessary aerodynamic drag are important. A flush rivet takes advantage of
a countersink hole; they are also commonly referred to as countersunk rivets. Countersunk or
flush rivets are used extensively on the exterior of aircraft for aerodynamic reasons. Additional
post-installation machining may be performed to perfect the airflow.

Friction-lock rivet These resemble an expanding bolt except the shaft snaps below the surface when the
tension is sufficient. The blind end may be either countersunk ('flush') or dome shaped.
One early form of blind rivet that was the first to be widely used for aircraft construction and
repair was the Cherry friction-lock rivet. Originally, Cherry friction-locks were available in two
styles, hollow shank pull-through and self-plugging types. The pull-through type is no longer
common, however, the self -plugging Cherry friction-lock rivet is still used for repairing light
aircraft.
Cherry friction-lock rivets are available in two head styles, universal and 100 degree
countersunk.

Self-pierce rivets Self-pierce riveting (SPR) is a process of joining two or more materials using an engineered
rivet. Unlike solid, blind and semi-tubular rivets, self-pierce rivets do not require a drilled or
punched hole.
SPRs are cold forged to a semi-tubular shape and contain a partial hole to the opposite end
of the head. The end geometry of the rivet has a chamfered poke that helps the rivet pierce
the materials being joined, a hydraulic or electric servo rivet setter drives the rivet into the
material, and an upsetting die provides a cavity for the displaced bottom sheet material to
flow.

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