Q5-5.
What is the purpose of placing a washer
under the head of a bolt?
TURNLOCK FASTENERS
LEARNING OBJECTIVE:
Recognize the
three common types of turnlock fasteners
(quick-action panel fasteners) and how they
operate.
Turnlock fasteners are used to secure plates, doors,
and panels that require frequent removal for inspection
and servicing. Turnlock fasteners are also referred to as
quick-action panel fasteners. These fasteners are
available in several different styles and are usually
referred to by the manufacturer's trade name. Some of
the most common are the Camloc, Airloc, and Dzus.
CAMLOC FASTENERS
The Camloc 4002 series fastener consists of four
principal partsreceptacle, grommet, retaining ring,
and stud assembly. See figure 5-9. The receptacle
consists of an aluminum alloy forging mounted in a
stamped sheet metal base. The receptacle assembly is
riveted to the access door frame, which is attached to
the structure of the aircraft. The grommet is a sheet
metal ring held in the access panel by the retaining ring.
Grommets are available in two typesthe flush type
and the protruding type. In addition to serving as the
grommet for the hole in the access panel, it also holds
the stud assembly. The stud assembly consists of a stud,
cross pin, spring, and spring cup. The assembly is
designed so that it can be quickly inserted into the
grommet by compression of the spring. Once installed
in the grommet, the stud assembly cannot be removed
unless the spring is again compressed.
5-7
OUTER MEMBER
STUD ASSEMBLY
GROMMET
GROMMET
RETAINING
RING
RIVET
INNER
MEMBER
RECEPTACLE
STUD
RETAINING
RING
OUTER MEMBER
STUD ASSEMBLY
GROMMET
GROMMET
RETAINING
RING
INNER
MEMBER
RECTACLE
STUD ASSEMBLY
FLUSH OR
PROTRUDING
GROMMET
GROMMET
RETAINING
RING
STUD RETAINING
RING (USED ON
SOME FASTENERS)
RECEPTACLE
PROTRUDING TYPE INSTALLATION
FLUSH TYPE INSTALLATION
RIVET
ANF0509
Figure 5-9.Camloc 4002 series fastener.