Simrad ES38-12 - REV C, Руководство по установке, Страница: 31 / 46

Transducer handling and maintenance
Introduction to Emuge self-locking threads
Emuge self-lock
is a tap design with an integrated locking feature. Standard metric bolts
are used. The internal thread provides a self-locking connection, which can be used
repeatedly. It is not necessary to involve a secondary locking device (e.g. chemical,
nylon or mechanical). The
Emuge self-lock
bolts withstand vibrations better than standard
(metric) threads, because the thread contact stops the sideways movement. The special
design of the internal thread profile also provides a more even distribution of the
tightening stress over the whole thread length. The assembly is just as easy as with a
normal (metric) thread. There is no general applicable standard (e.g. DIN standard)
for the
Emuge self-lock
thread.
Figure 18 Example, internal and external threads
A Emuge’s saw-tooth profile up to pitch P ≤ 0.7 mm
B
Emuge’s saw-tooth profile up to pitch P ≥ 0.7 mm
C Standard thread
1
External thread
2 Internal thread
Advantages
• The thread locking feature is integrated in the internal thread
• Modified profile with ramp surface in the direction of stress
• 30 degree ramp surface provides self-locking effect
• Easy assembly
• No assembly errors (forgetting the locking device) possible
• Use of standard external threads (screws) with tolerance class “medium”
• Even distribution of stress over the whole thread length
• No stripping of threads
• Economically efficient locking system, no additional components are necessary
• Undiminished holding power even under dynamic stress
• Repeated loosening and re-tightening without loss of function
344276/A
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