Metallic Structures Flashcards
What is another name for GTA welding?
TIG welding.
What is used as the electrode in GTA welding?
A small-diameter tungsten wire.
What are three types of power that can be used for GTA welding?
DC-straight polarity, DC-reverse polarity, and AC.
Which type of power is used for GTA welding aluminum and magnesium?
DC-reverse polarity.
Which type of power provides the greatest heat and deepest penetration in GTA welding?
DC-straight polarity.
What must be done to an aircraft fuel tank before it can be repaired by welding?
The gasoline fumes must all be purged from the tank by running live steam through it for at least 30 minutes, by soaking it in hot water, or by filling it with nitrogen or carbon dioxide.
When drilling out rivets on an airplane or drilling holes for repair, what precaution should be taken?
Do not allow the drill to enter into the space behind the structure, as the drill may cause damage to other structures or systems.
How do you determine the length of a solid rivet for installation?
Grip length + one and a half times the shank diameter.
What is a bonded honeycomb construction?
Two relatively thin, parallel face sheets bonded to and separate by a relatively thick, lightweight core.
Name two core materials used special applications of bonded honeycomb construction?
Kraft paper, thermoplastics, aluminum, steel, titanium, aramid paper, fiberglass, carbon, or ceramics.
Name two causes of delimitation or debond of a honeycomb construction?
Matrix cracks, High or low-energy impacts, Subject to repeated loading, liquid ingression, Manufacturing/production flaws, Non-adhesion, poor fastener installation, improper hole drilling.
What should be done to twist drills that are to be used for drilling completely through plexiglas?
Drill must be free from nicks and burrs that would affect the surface finish. Grind the drill with an included angle of 150 degrees. That rake angle should be 0 degrees in order to scrape and not cut.
