fluid line and fittings Flashcards
of what material are most low pressure rigid fluid lines made
1100-1/2 hard or 3003-1/2 hard alloy tubing
is the size of a rigid fluid line determined by its inside or its outside diameter
by its outside diameter
what is the difference between the flare angle for aircraft and automotive fittings
aircraft fittings have a 37 degree flare able and automotive use 45 degrees
where are quick-disconnect fluid line coupling normally used in an aircraft hydraulic system
in the lines that connect the engine-driven pump into the hydraulic system
is the size of a flexible hose determined by its inside or its outside diameter
by its inside diameter
of what material should rigid fluid lines be made that carry high pressure (3,000 psi or greater) hydraulic fluid
annealed or 1/4 hard corrosion- resistant steel
what is the principal advantage of teflon hose for use in an aircraft hydraulic system
teflon hose retains its high strength under conditions of high temperature
how tight should an MS flareless fitting be tightened
Tighten the fitting by hand until it is snug, and then turn it with a wrench for 1/6 turn to 1.3 turn. never turn it more than 1/3 turn with a wrench
what damage can be caused by overtightening an MS flareless fitting
overnighting drives the cutting edge of the sleeve deep into the tube and weakens it
what kind of rigid tubing can be flared with a double flare
5052-O and 6061-T aluminum alloy tubing in sizes from 1/8inch to 3/8 inch OD
what should be done to the end of a tube that is to flared
the cut end should be polished to remove any sharp edges that could cause the tubing to crack
what is the minimum amount of slack that must be left when a flexible hose is installed in an aircraft hydraulic system
hose should be at least 5% longer than the distance between the fittings. This extra length provides the needed slack
how much pressure is used to proof test a flexible hose assembly
this varies with the hose, but is generally about 2 times the recommended operating pressure for the hose
why is it important to use a torque wrench when securing fluid hose and line fittings
if the connection is too loose, it may leak. if the connection is too tight, it can cause the fitting to become damaged and fail
what is the purpose of using torque seal on a critical fitting after installation
if a visual inspection reveals that the torque seal has broken, it is an indication that the fitting may has loosened
