DCC 1023 Rivet Joint
Rivets
Rivets are a permanent mechanical fastener. Before
being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite the head is
called the buck-tail. On installation the rivet is placed in a punched
or drilled hole, and the tail is upset, or bucked (i.e.,
deformed), so that it expands to about 1.5 times the original shaft diameter,
holding the rivet in place. To distinguish between the two ends of the rivet,
the original head is called the factory head and the deformed end is
called the shop head or buck-tail.
Because there is effectively a head
on each end of an installed rivet, it can support tension loads (loads parallel
to the axis of the shaft); however, it is much more capable of supporting shear
loads (loads perpendicular to the axis of the shaft). Bolts and screws are
better suited for tension applications.
Fastenings used in traditional
wooden boat building, such as copper nails and clinch bolts, work on the same principle as the rivet but were in use
long before the term rivet was introduced and, where they are
remembered, are usually classified among nails and bolts respectively.
Types
There are a number of types of rivets, designed to meet different cost, accessibility, and strength requirements:Solid/round head rivets
A typical technical drawing of a universal head solid rivet
Solid rivets are one of the oldest and most reliable types of fasteners,
having been found in archaeological findings dating
back to the Bronze
Age. Solid rivets consist simply of a shaft and head that are
deformed with a hammer or rivet gun. A rivet compression
or crimping tool can also deform this type of rivet. This tool is mainly used
on rivets close to the edge of the fastened material, since the tool is limited
by the depth of its frame. A rivet compression tool does not require two
people, and is generally the most foolproof way to install solid rivets.
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