Forming Test Review Flashcards
Why is there a minimum bend radius established when forming metals?
To prevent critically weakening the metal at the bend
What is Springback related to sheet metal forming?
The natural tendency for a piece of metal being cold formed to slightly return back to the original form when force is removed
What is the minimum size drill bit used on Relief holes
1/8 or #30
Figure
(SB)
(BA)
(TL)
(SB) .0525322
(BA) .089799
(TL) 6.984746
Aluminum should be bent ________ the grain
Against
What is the purpose of a Relief Hole?
It prevents cracking or tearing at the intersection of two bends
What is closed angle?
Acute or less than 90 degrees when measured
What type of brake is used to bend flat sheet metal into boxes?
Box and Pan Brake
What tool is used to make folds along only the edge of the metal?
Bar Folder
A bend tangent line is?
The line where the metal starts to bend and where it stops bending
What tool is used to make cylinders?
Slip Form Roller
What is the short part of a formed angle called?
Flange
An open angle is?
Obtuse or more than 90 degrees
What is the purpose of a Joggle?
To prove clearance for a sheet or extrusion
Where is the radius of a bend measured?
Inside the bend or curve
Where is the sight line placed if we bend metal 90 degrees from flat
Within the bend allowance area one bend radius from the bend tangent line
What is the function of a lightning hole?
To reduce the overall weight of the part
What is the Cornice brake designed for use in?
Making folds in metal
Holes are drilled at their intersection of two bends to prevent cracking, what are these holes called?
Relief Holes
Would you use conventional hand shears on Magnesium
Never
The distance from one bend tangent line to the other bend tangent line is called?
Bend Allowance
When bending metal the area not affected by either compression or stretching is called?
Neutral Line
What does crimping do to a piece of metal being worked?
It shortens the piece of metal by creating a series of folds, pleating or corrugating the metal.
What is the long part of a formed angle called?
Leg
Lightning holes should never be cut into structure unless authorized?
True
A piece of flat stock that is bent to 37 degrees what type of angle is this?
Closed or Acute
What would be the bend allowance for a piece of stock to be bent at 90 degrees, 1/4 Radius, .040 thickness
.421
What is the maximum working pressure for Acetylene gas?
15 PSI
What is Backfire?
Momentary backward flow of the gasses at the tip
What is the purpose of the inert gas that is used to TIG weld?
It creates a shield to keep oxygen away from the weld puddle so oxides cannot form
What determines the amount of heat that is applied to the metal?
Size of torch tip opening
An oxidizing flame consist of too much what?
Oxygen
What determines the size of the torch tip?
Thickness of the mental being welded
What is flashback?
Overheating of the torch
What voltage and amperage setting is used in electrical resistance welding?
Low voltage, High Amperage
What are the characteristics of a good weld?
It should taper off smoothly into the base metal
