Ch 18 Machining operations and Machine Tools
What are the different types of Face milling?
1. Conventional face milling 2. Partial face milling 3. End milling 4. Profile milling 5. Pocket milling 6. Surface contouring
Give two examples of machining operations in which generating and forming are combined to create work part geometry.
1. Thread cutting on a lathe 2. Slot milling
What are the two forms of peripheral milling?
1. Up milling 2. Down milling
A lathe can be used to perform which of the following machining operations (three correct answers): 1.boring, 2.broaching, 3.drilling, 4.milling, 5.planing, 6.turning
1. boring 3. drilling 6. turning
Describe knurling
A metal forming operation used to produce a regular crosshatched pattern in the work surface
Describe chamfering
Cutting edge cuts an angle on the corner of the cylinder, forming a "chamfer".
Distinguish between generating and forming when machining work part geometries.
Each machining operation produces a characteristic part geometry due to two factors: 1. Relative motions between the tool and the work part. GENERATING: part geometry is determined by the feed trajectory of the cutting tool. 2. Shape of the cutting tool. FORMING: part geometry is created by the shape of the cutting tool.
Describe milling
Is a process of producing flat and complex shapes. Milling is one of the most versatile, efficient process for metal removal and widely used machining operations. Well suited for mass production applications. Milling operations are classified into two major categories: 1. Peripheral milling 2. Face-/end milling
Describe form turning
The tool has a shape that is imparted to the work by plunging the tool radially into the work.
Describe facing
The tool is fed radially inwards
What is the difference between threading and tapping?
Threading is performed on a turning machine and produces an external thread. Tapping is performed on a drilling machine and produces an internal thread.
Describe cutoff
Tool is fed radially into the rotating work at some location to cut off end of part
Describe the turning process.
Turning is a machining process in which a single-point tool removes material from the surface of a rotating workpiece to generate a cylindrical shape. Performed on a lathe.
What are the variations of turning that are performed on a lathe?
1. Facing 2. Contour turning 3. Chamfering 4. Cutoff 5. Threading
What are the different types of Peripheral milling?
1. Slab milling 2. Slotting 3. Side milling 4. Straddle milling 5. Form milling
In a turning operation, the change in diameter of the workpart is equal to which one of the following: 1. 1 x depth of cut 2. 2 x depth of cut 3. 1 x feed 4. 2 x feed 1.boring, 2.broaching, 3.drilling, 4.milling, 5.planing, 6.turning
2. 2 x depth of cut
Reaming is used for which of the following functions (three correct answers): 1. accurately locate a hole position, 2. enlarge a drilled hole, 3. improve surface finish on a hole, 4. improve tolerance on hole diameter, 5. provide an internal thread
2. enlarge a drilled hole 3. improve surface finish on a hole 4. improve tolerance on hole diameter
The basic milling machine is which one of the following: 1.bed type, 2.knee-and-column, 3.profiling mill, 4.ram mill, 5.universal milling machine
2.knee-and-column
A tap is a cutting tool used to create which one of the following geometries: 1.external threads, 2.flat planar surfaces, 3.holes used in beer kegs, 4.internal threads, 5.square holes?
4. internal threads
Describe contour turning
Instead of feeding the tool parallel to the axis of rotation, tool follows a contour that is other than straight, thus creating a contoured form.
How does a boring operation differ from a turning operation?
Boring produces an internal cylindrical shape from an existing hole mad by drilling or another process, while turning produces an external cylindrical shape. In effect, boring is an internal turning operation.
Describe taper turning
Instead of feeding the tool parallel to the axis of rotation of the work, the tool is fed at an angle thus creating a tapered cylinder of conical shape.
Describe threading
Pointed form tool is fed linearly across surface of rotating work part parallel to axis of rotation at a large feed rate, thus creating threads.
What are the differences between rotational parts and prismatic parts in machining?
Rotational: Work part rotate and have a cylindrical/disk - like shape. Turning and Boring. Prismatic/Nonrotational: The tool has a rotating or linear motion. Work part is block- or plate-like and have a linear motion. Milling, Shaping, Planing and Sawing.
Describe the difference between up milling and down milling.
Up milling: the direction of motion of the cutter teeth is opposite the feed direction when the teeth cut into the work. Down milling: the direction of cutter motion is the same as the feed direction when the teeth cut into the work.
