6.6 Flashcards
What does the wall thickness of a rigid tube go up in increments ?
1/8 inch
What fluid line would hold over 1500psi ?
High pressure
( aluminium alloy )
What fluid line would hole under 1500psi ?
Medium pressure lines
( aluminium alloy )
What material for fluid lines is used in engines ?
Steel due to heat and possible fod damage
What increments is used for the part number of a rigid tube ?
1/16
Where is the wall thickness printed on a tube ?
Outside in thousandths of an inch
What’s written on outside of pipe ?
Date of manufacture, inspection stamp, system identification.
Whats 2 ways of identifying a tubes alloy designation ?
- Colour code on surface
- Stamped on surface
What colour of band is 2024 alloy ?
Red
How are fluid lines identified ?
By tape or decal made jump of colour codes.
- this also shows each lines function, fluid content, and hazards.
What can be used to mark fluid lines in oily hot or cold environment ?
Steel tags
Whats used to mark fluid lines in engine ?
Paint due to any tags etc being sucked into the engine.
Fluid lines marked PHDAN means what ?
It carry’s dangerous materials - oxygen, nitrogen, freon
What’s the two common pipe fittings
- Standalone fitting
- Ball valves
What does a flared tube consist of ?
- Sleeve
- Flare nut
What’s the use of a flare nut and sleeve ?
Flare nut attaches tube to other tube or components whilst the sleeve protects nut from damage. Sleeve also adds strength against vibration.
What’s the flare angle of aircraft fittings ?
37 degrees
What’s the two types of flares used in aircraft piping systems ?
- Single flare
- Double flare
How is a single flare formed ?
- Impact type flaring tool
Or rolling action
What flare does anything with a outside diameter under 3/8 inch have ?
Double flare
What advantage does a double flare have over a single flare ?
- Provides better seal
- More durable and resistant to shearing
What should you not do to a leaking fitting on tube ?
Over tighten it
What’s the 2 flared fittings identifications
AN - Army,navy
AC - Air corps
What’s the difference of a AN (army navy) fitting to a AC (air corps) fitting ?
AN - has a shoulder between end of thread and flare cone, and is longer.
AC - doesn’t have shoulder, and is shorter.
What colour are AN steel and AN aluminium fittings ?
AN steel - Black
AN aluminium - blue
What are flareless tube fittings used for ?
To attach two sections of pipe together and commonly have a sleeve in them.
How do you create a strong leak free joint in assembly of a flareless tube fitting ?
Tighten nut compressing sleeve between receiving fitting.
What’s the two types of flared fitting ?
MS Fitting
Harrison fitting
What three parts does a Harrison fitting consist of ?
- Tube
- Sleeve
- Nut
What colour is aluminium alloy flareless fittings
Green ( caused from anodizing treatment.
How is the material which the fittings is made from indicated on MS number ?
There is an absence of a letter or addition of a letter at end of number.
What’s the common repair system used for repairing hydraulic systems ?
Permaswage fittings
What do swaged fittings create ?
Permanent connection which is virtually maintenance free.
What are swaged fittings used to connect ?
Hydraulic lines in areas where routine disconnections are not required.
( used with titanium and CRES tubing )
How is swaged fitting installed ?
Portable hydraulic powered tool
( small enough to use in confined spaces )
How do you disconnect fittings on tube ?
Cut tube with tube cutter
How is permalite fittings attached ?
Mechanically attached by axial swaging
What’s a common component of a permalite fitting ?
Moving ring
What are flexible fluid lines constructed from ?
Synthetic compounds
( provides flexibility )
Where are flexible fluid lines used ?
- Connecting moving parts to stationary parts
- Locations subject to vibration
- Where great amount of flexibility is needed
( sometimes use as a connector for metal tubing )
What components does a flexible fluid line consist of ?
- Inner liner - carrying fluid
- Reinforcement layer
- Protective outer cover - protect from physical damage
( material used and manufacturing process for hose determines on application hose is used for. )
What’s 3 materials a inner line on flexible hose is made from ?
- Neoprene
- Buna-N
- Butyl
- Teflon - Broad operating temp of -240 degrees to 204 degrees
What common 3 materials can a reinforcing layer in a flexible hose be made from ?
- Cotton
- Steel braid
- Carbon steel wire
What 2 materials can a outer cover Of a flexible hose made from ?
- Rubber
- Steel braid
What information is found on lay lines on flexible hoses ?
- Manufacture information
- Mil-Spec numbers
- Indicates weather assembly is twisted when installed
What’s a flexible hoses inside diameter measured in ?
1/16 inch increments
( dash number indicates tube diameter )
E.G. ( a-10 )-> 10/16 of inch
What’s maximum operating pressure of low pressure hose ?
Up to 600psi
What’s maximum operating pressure of medium pressure hose ?
Up to 3000psi
( Maximum pressure depends on their diameter )
What is used as outer cover for medium pressure hose?
Cotton
What’s the maximum pressure of a high pressure flexible hose ?
Over 3000psi
Can swaged end fittings be removed and reused ?
No. Reusing fitting causes leakage.
What does a re-usable fitting consist of ?
- Socket
- Nipple
- Nut
What has to happen prior to re-using any fittings ?
Must be removed from damaged hos and carefully inspected.
Should you mix components manufactured by different companies ?
No
What should be placed on open ends of a fluid line when removed / disconnected ?
Blanking caps, tightened with wrench to prevent leakage.
( made from plastic, wood, metal )
What’s the purpose of a swivel fitting ?
Allows the coupling and hose connection to rotate.
What’s 7 advantages of a swivel fitting ?
- Extends hoss life
- Reduces maintenance needed
- Reduces length of hose needed between connections.
- Eliminate use for bent tubing
- Connected to hose line without adapters
- Compensates for hose length changes.
- Simplify hose installation
What 2 components does a swivel fitting consist of ?
- Stem
- Housing
( rotate relative to one another )
( rotate 360 degrees )
What does couplings provide ?
Quick connection / disconnection capabilities with self - sealing action
( used on ground support equipment )
What’s 3 advantages of couplings ?
- Offer one-hand operation
- Self-sealing
- Eliminate vapour loss
What are gamah couplings used for ?
Fuel,water,waste and oxygen systems
What’s the components of a gamah coupling ?
- Aluminium sleeves
- Clamps
- O-rings
- Swaged flanges
How can the flange swage process be carried out ?
- Manually
- By machine
What does the flange On a gamah coupling provide ?
Maximum angular movement without transferring load to clamp.
What does the double hinged design of clamp on gamah coupling allow ?
Eases fittings in tight spaces
What has to happen for gamah coupling In order to open it ?
All three paw latch locks have to be lifted
Where do you use v- retainer couplings ?
- Connecting in high temp, pressure and mechanical applications.
- Connect Bleed air ducts
- Exhaust systems
- Connections which are frequently put together and taken apart.
Fb
Whats the two v-couplings types ?
- V - retainers
- V - bands
What Can a t-bolt be tightened with ?
Hex-nut ( to create seal )
When is a t-bolt used ?
When access is limited.
Difference between V-retainers and V-bands ?
V-retainers have single retainer segment and v-bands have multiple.
Whats worm gear hose clamps ( jubilee clips ) used for ?
- Secure hose
( made from zinc-plated steel )
What components make up a worm drive clamp ?
- Slotted band
- Screw housing
- Worm gear
- Screw
