Machining Operations Flashcards
What are some classifications of machined parts?
Rotational or nonrotational
How are rotational figures shaped?
Cylindrical or disk-like (piece is rotated to form circular shape)
What form do nonrotational pieces take?
Block or plate like structures
What is generating?
When the feed trajectory of the tool is what determines the geometry of the part
What is forming?
The shape of the tool part is what determines the geometry of the part
What is turning?
Cutting tool touches workpiece at single point, where the piece is then rotated and the tool is fed towards the uncut material
What machine performs turning?
Lathes
What axes of motion do lathes have?
Across the workpiece, and into the workpiece
Why are the cutting tools in lathes considered stationary?
The tool itself is placed at a point on the workpiece, and is moved across via the bed
What types of turnings are generating?
Straight, taper, profile, grooving, facing, and face grooving
What types of turnings are forming?
Form cutting, boring, drilling, removing, threading, and knurling
What is facing?
Turning process that dulls the edges of a shaft; cutting tool is fed radially inward
What is contouring?
Turning process where the feed is not linear, and instead follows a curved path
What is chamfering?
Cutting tool angles the corner of a piece, dulling edges
What is parting/cut-off?
Tool is radially inserted into work piece to cut off end of part
What is threading?
Specially shaped cut tool is fed across workpiece at high feed rates, creating threads
How can drilling be done through turning?
The drill bit is setup in the tailstock and pushed towards the workpiece
What is the tailstock?
A part of the lathe the supports the free end of the workpiece
Why might drilling through a lathe be more desired than regular drilling?
Since the drill bit is held by the tailstock, it is guaranteed to be on center relative to the stock material
What is boring?
The turning process of enlarging holes made by drilling by feeding a boring bar through
What is the feed rate?
the speed a tool is fed across the work piece; feed rate is given in terms of length/min, while feed is given in terms of length/revolution
What is the ideal turning process in terms of number of procedures
One roughing cut, one finishing cut
What is the chip’s cross-sectional area based on (turning)?
Feed and cut depth
What is the cutting time based off of (turning)?
Length of piece and feed rate
What are some specifications of the lathe?
Sizing, RPM, horsepower
What is the lathe’s bed?
Where headstock, tailstock, and carriage are held
What is the headstock?
Lathe part that contains the spindle
What is the spindle?
Lathe part that holds and rotates the workpiece
What is the carriage?
Part that holds the cross slide, which houses the tool, also what feeds the tool into the workpiece
What is the feed rod?
Allows the carriage to move
What are some ways the piece is held in the lathe?
Between centers, chuck, collet, face plate
How does holding the work between two centers work?
One center is held in head stock by dog (part that stabilizes and holds piece while it rotates), and the other end is held by a cone shaped point at tailstock
How does holding the work with a chuck work?
Located at the headstock, chuck clamps down on workpiece, and chuck itself rotates
How does holding the work with a collet work?
Cylindrical piece that squeezes down on work piece
What is the difference between an engine and toolroom lathe?
Engine lathes are the general type found in shops, toolroom lathes are smaller but more accurate
What is a turret lathe?
Swiss army lathe (“turret” holds various tools)
What is the difference between drilling and turning?
Work piece is stationary, and does not rotate
