Screw Threads Flashcards
What do letters A and B mean on screw threads?
A - male external
B - female internal
What thread class are aircraft bolts manufactured to?
Class 3, medium fit
What are the 5 classes of thread fit in order?
Class 1 - loose
Class 2 - free
Class 3 - medium
Class 4 - close
Class 5 - tight
What are the 3 types of power transmission thread?
Square thread - aircraft lifting jacks
ACME thread - a modified square thread with sloping sides
Buttress thread - triangular, one side 90 degrees, axial loads in one direction only
What unified threads are used in the aerospace industry?
UNC, UNF, UNJF, MJ (metric screw thread)
What standards are thread fasteners and rivets identified by?
Air Force Navy
National Aircraft Standards
Military standards
What are the 7 types of fastener?
Bolts
Screws
Nuts
Wing nuts
Studs
Dowel pins
Clamps
9 types of fastener head?
REVISE WHAT THEY LOOK LIKE
Straight
Hi torque
Philips
Posidrive
Reed and prince
Torque set
Tri-wing
Torx
Allen
What are the 6 types of machine screw heads?
Round
Fillister
Cheese
Pan
Mushroom
Socket
Name 3 types of quick release fastener
Duz fastener
Oddie fastener
Camloc fastener
What fit is a general purpose thread?
Class 2
What thread has a face at 45 degrees?
Buttress
What does J mean on a unified thread?
Made in both external and internal forms
Where can you find the hole sizes to drill prior to tapping?
ZEUS book
Whats the thread angle of a metric thread?
60 degrees
