FUEL SYSTEM
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INTERCHANGEABILITY:
Intermixing and interchanging tube fitting
components of different manufacturers can be
dangerous.
Leak-tight seals that will withstand high pressure,
vibration, vacuum, and temperature changes depend
on close tolerances and consistent, exacting quality
control in conjunction with good design principles.
The critical interaction of precision parts is essential
for reliability and safety
B
.
PROCEDURE FOR NPT THREAD ASSEMBLY
NPT threads assembly should be completed in a
clean environment to prevent any dirt or foreign
material from entering the end-connection.
STEP 1
1 Remove the thread protector from the male
threads.
2 As the thread protector is removed from the male
threads, bits of plastic from thread protector may
remain in the mail threads.
3 Remove this material from the threads using a
clean, dry, soft-bristled brush
STEP 2
Check components to ensure minimum thread
engagement.
1 Tighten the male end-connection into the female
end-connection until finger tight.
2 Mark the wrench flat on the male component.
3 While holding the female component stationary,
loosen the male component while counting the
number of turns until the two components
separate.
4 The minimum allowable thread engagement is 2
turns. Therefore, if you can not engage at least
2 turns, do not use this combination of male and
female components. Select a different
combination of components and repeat this step
until the
MINIMUM 2
thread engagement is
achieved.
WARNING:
Do Not Assemble Components With Less Than 2
Turns Of Thread Engagement.
STEP 3
Where possible; place the component containing the
female threads into a vise (preferably one with
smooth jaws).
NOTE:
Tighten the jaws only on the
flats.
Tighten just enough to securely hold the
component as over tightening could result in
damage to the component.
Use an additional wrench in applications where a
vise cannot be used.
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