Figure 4-10.--Rivet gun internal airflow.
See figure 4-10. Regulated air entering the gun passes
through the handle and throttle valve, which is
controlled by the trigger, and into the cylinder in which
the piston moves. Air pressure forces the piston down
against the rivet set and exhausts itself through side
ports.
The rivet set recoils, forcing the piston back. Then
the cycle is repeated. Each time the piston strikes the
rivet set, the force is transmitted to the rivet. Rivet sets
come in various sizes to fit the various shaped rivet
heads. Rivet set retainer springs must be used on all
pneumatic rivet sets to prevent the set from being
discharged from the gun when the trigger is pulled.
Several types of pneumatic riveters are in general
use. They are the one-shot gun, slow-hitting gun,
fast-hitting gun, corner riveter, and the squeeze riveter.
See figure 4-11. The type of gun used depends on the
particular job at hand, with each type having its
advantages for certain types of work. One person can
rivet small parts if the part is accessible for both
bucking and driving. The greater part of riveted work,
however, requires two people.
Rivet Guns
The size and the type of gun used for a particular
job depend upon the size and alloy rivets being driven
and the accessibility of the rivet. For driving
medium-sized, heat-treated rivets that are in accessible
places, the slow-hitting gun is preferred. For small, soft
alloy rivets, the fast-hitting gun is preferable. There will
be places where a conventional gun cannot be used. For
this type of work, a corner gun is employed.
Figure 4-11.--Various types of rivet guns.
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