Maintenance Practices M7.9 Flashcards
How are tube sizes dertermined
External diameter and wall thickness
When is aluminium used for solid tubes
Low pressure lines or 1500psi or lower
When manufacturing pipes how would they be tested
To 1.5 times system pressure
When installing bonded clamps what must be remembered
All surface protection and paint must be removed to ensure good bonding
Aircraft pipe flares are what angle
37°
What must you do if there is a slight leak in a joint
Do not over tighten. Back off, clean and retorque to ensure nothing is damaged
What tool is preferred to flare pipes
Roll type tool 37°
What pipes would you find a double flair
Soft aluminium tubing 3/8 diameter or smaller
What is Harrison type suage fitting
Well suited for thin walled tubes and vibration resistant
What is a permasuage fitting
Permanent and not separable.
Big disadvantage you can’t disassemble
What is done to help reduce stress when bending pipes
Lubricate the bending portion
What is used to calculate bends other than simple 90°
Offset bend calculator
What must be mindful when replacing aluminium pipes for CRES or titanium if allowed
There will be a weight penalty
What is permissible damage in sharp bottom defects in solid pipes
5% wall thickness or scrap
What is permissible in round bottom defects
10% wall thickness or scrap
