Flashcards in Chapter 16 Deck (36):
What two factors decide characteristic part geometery
Relative motion b/w tool and workpart.
Shape of the cutting tool
What is generating
Generating - part geom determined by feed trajectory of cutting tool
What is forming (3)
Forming - shape of cutting tool determines the geometry of the part.
Form turning, drilling, and broaching
What is turning? Name some (9).
Single point cutting tool.
Rotate the workpiece.
Facing, taper turning, contour turning, form turning, chamfering, cutoff, threading, boring, drilling
What is a turret lathe
Six tools instead of the tailstock.
High production that requires sequence of cuts
What is chucking machine
Chuck hold workpart.
Operator only load/unloads parts.
Short, light weight parts
What is a bar machine
Collet hold workpart usually a bar.
Cutoff after operation.
Highly automated. CNC.
High prod of rotational parts
What is an automatic screw machine
Same as bar machine but smaller.
High prod of screws and similar hardware items
What are multiple spindle bar machines
Multiple parts machined then rotated.
What is the six spindle bar machine process
Turn main D
Form second D and spotface
State Chuck for lathe (2)
Easy to locate. Self centering. Only round part.
Long time to locate. Rect part. Eccentric turning.
State Lathe steadies or rests
Steady Rest and Follower rest
Support long jobs.
Support at tailstock.
Dead centre or revolving centre
Inside diameter of existing hole to make larger. Horizontal or vertical
Explain Drilling and simlilar (6)
Creates a round hole unlike boring.
Reaming, tapping, counterboring, countersinking, center drilling, and spot facing.
How to hold workpart for drill presses? (3)
Vise - two jaws
Fixture - Custom-designed for part
Drill jig - custom-designed and guides the tool during drilling
What is milling? Explain difference b/w peripheral and face
Workpart moves; multiple cutting edges tool fixed.
Peripheral - Cutter axis parallel to surface
Face - Cutter axis perpendicular to surface.
Name peripheral mills (5)
Name face mills (6)
Profile w/ end mill
Name the two mills
Horizontal - peripheral
What is a machining center?
3, 4, 5 axes. CNC control. Automated.
Mill-turn center vs conventional turning center (2)
Position cylindrical part at an angle. Includes rotating tool spindles.
Process of Mill-turn center (4)
Turn second D
Diff b/w down and up milling
Down: Same direction as workpart. Good surface finish.
Up: Opposite direction of workpart. More safe since amount of material taken off smaller so less chance of breaking tool.
Diff b/w shaping and planing (3)
Shaping: Workpart moves feed. Smaller pieces 1 to 2m.
Planing: Tool moves feed. Large pieces 10m. Only stroke cuts so not efficient
Explain broaching process and characteristics (6)
Seq. - Roughing, semi-finishing, and finishing teeth.
Internal or external
Good finish, accurate dim, expensive but one pass. Made from steel since mainly tension, starter hole and through features only
Explain sawing. Name saws (3)
Cuts narrow slit in work.
Power hacksaw - linear reciprocated/one direction. Short, rigid
Band Saw - Linear continuous motion. Flexible, irregular shape, aluminum
Circular Saw - Rotating saw. Continuous. Ceramic.
Describe teeth type
Straight - Copper or brass
Raker - Steel and iron
Wave - Thin sheet
Describe Filing. Name four.
Fine wide teeth. Small chips. Finishing/deburring
Single, Double, Rasp, Vixen
Name three burs
High speed steel
What is HSM: DN ratio
Bearing bore diameter mult by max spindle speed
1 mil to half a mil
What is HSM: HP/RPM
Ratio of hp to max spindle speed.
Req. for high speed machining (6)
High feed rate
Coolant delivery that give higher pressure
What determines surface roughness? (3)
Geometric factors - Type of machining operation. Tool geom and feed.
Work material factors - Built-up edge effects. Crack in surf or friction b/w flank and surface.
Vibration and machine tool factors - Tool chatter. Backlash in feed mechanism.
How to avoid tool chatter (5)
Dampen or stiffen
Speeds not within natural frequence.
Reduce feeds and depths
Change cutter design