Post on 31-Oct-2020
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MANUFACTURING TECHNOLOGY
October 2019
PART – A
1. Write lathe specification
(Diagram = 1 mark
Explanation = 1 mark)
2. What are the uses of quick return mechanism
Generally the cutting operation only in the forward stroke, and backward stroke is
ideal and therefore wastage. In order to minimize this wastage the return stroke should be
completed as quickly as possible.
3. What is countersinking operation?
To extend a holes face area in a tapered profile is called counter sinking. This
Operation is aimed to seating a screw with tapered head.
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(Diagram = 1 mark
Explanation = 1 mark)
4. What is up – milling and down milling?
Up milling – it is the process of removing metal by a cutter rotated against the direction
of travel of the work piece. Here the cutting takes place when the cutter moves upward. this
method is also called “Conventional Milling”.
Down milling – it is the process of removing metal by a cutter rotated in the same
direction of travel of the work piece. Here the cutting takes place when the cutter moves
downward. this method is also called “Climb Milling”.
(Diagram = 1 mark
Explanation = 1 mark)
5. How broaches are classified?
1. According to the method of operation
(a) Push broach (b) Pull broach
2. According to the kind of operation
(a) Internal broach (b) External broach
3. According to their construction
(a) Solid broach (b) Over lapping teeth broach (c) Built up of replaceable section
(d) Inserted tooth broach (e) progressive cut broach
4. According to the function,
Key way, surface, round hole, spline, spiral, burnishing broach etc.
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6. Differentiate ECM and EDM
Sl.no ECM EDM
1. Electro chemical machining Electrical discharge machining
2. Machining done by chemical attach Machining done by high voltage spark and
arc
3. Chemical etchant used to chemical metal
removal
Tool cathode, work piece anode. Dielectric
fluid used.
7. Define accuracy.
Accuracy is degree of alignment of true value and measured value.
8. Write the purpose of dressing of grinding wheel
Removal glazing and loading from a grinding wheel is the purpose of dressing.
(Diagram = 1 mark
Explanation = 1 mark)
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PART – B
9. Describe any four types of shaping tools
1. Round nose tool
This type of tool is used for roughing operations. It may have side rake angle
between 100 to 20
0 and a side clearance angle between 2
0 to 4
0. This tool is of two types
namely, plain tool and bent tool. The plain tool is used for machining vertical surfaces.
Both the left hand and right hand types are available for this tool.
2. Square nose tool
This type of tool is used for finishing operations. The cutting edge of the tool may
have different widths. This tool can also used for machining the bottom surfaces of
grooves and key ways.
3. Side tool
Side tool is used for machining t-slots and narrow vertical surfaces. Both the left
hand and right hand types are available for this tool.
4. Parting off tool
This tool is used for cutting narrow slots and parting off the work piece. It has a
back rake angle of 30 and a side clearance angle 3
0
(Diagram = 1 mark
Explanation = 2 mark)
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10. Sketch planer work holding devices
(any three)
11. Write short notes on indexing of milling.
Indexing is equally dividing the periphery of circular workpiece for cutting gear
teeth for indexing dividing heads are used.
Methods of indexing:-
1. Direct indexing
2. Plain indexing
3. Compound indexing
4. Differential indexing.
1. Direct indexing
This method of indexing is used for small number of divisions in many identical
work pieces. This indexing can be done in both plain & universal dividing head spindle.
It has 24 equally spaced slots. A spring loaded pin is pushed into any one of the
holes to lock the spindles with the body while indexing.
2. Plain indexing
This indexing method is used for divisions that could not be indexed by direct or rapid
indexing. The universal dividing head is used for indexing. The dividing head spindle is
rotated by turning the index crank.
One complete turn of the index crank will make the spindle to turn 1/40th
of a
revolution.
For indexing a fraction of turn, an index plate having the suitable whole circle can
be used.
3. Compound indexing
This method is not used in practice. However this for academic interest, When it
Is not possible to divide the work piece by simple indexing, compound indexing method
is used
4. Differential indexing.
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This method of indexing is used for divisions that could not be indexed by simple
indexing by simple indexing. In differential indexing the required divisions on the work
piece is obtained by a combination of two movements
1. The index crank movement as in simple indexing.
2. The simultaneous movement of the index plate when the crank is turned.
12. What is truing of grinding wheels?
Truing is the process of changing the shape of the grinding wheel as it becomes
worn from an original shape, owing to the breaking away of the abrasive and bond. This
is done to make the wheel true and cancentric with bore or to change the face contour for
form grinding.
(Diagram = 1 mark
Explanation = 2 mark)
13. Describe the principle of broaching machine.
The work piece is set on the table by means of fixture. The broach is moved over
the surface in a fixed path. The broach has multiple cutting teeth along its length. The height of
tooth is gradually increasing. Each tooth removes a very small amount of metal.
The total metal removing is done progressively by each teeth. The machining is
done in one stroke of broach. The broach may be pulled or pushed over the surface of work
piece.
14. Write short notes on tolerance and surface finish
1. Surface finish – we cannot prodce any parts perfect smooth. There may be some
irregularities (hills and valleys) this is called surface texture or surface finish.
Surface finish is depend on following
1. Material
2. Machine tool
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3. Manufacturing processes
4. Cutting tool
5. Feed, speed & depth ct
6. Vibrations etc.
2. Tolerance –1. the permissible variation in size.
2. The difference between maximum limit and minimum limit
15. Write a note on plasma arc machining.
A gas has been heated to a high temperature (28000o C) to become partially
ionized and therefore electrically conductive. Plasma are maching is a thermal energy process. It
is done with a high speed jet of high temperature plasma.
16. Describe the nomenclature of drill.
1. Body
It is the main part of the drill. It has spiral flutes cut on it.
2. Shank
It is the part that fits into the machine spindle or any other holding device. The
shank may be tapered or straight. Morse taper is used for taper shank.
3. Tang
it is the flattened end of taper shank. It fits into the drift slot in the machine
spindle. The drill bit gets the drive from the spindle through the tang
4. Lip or cutting edge
It is the edge which actually cuts the material . There are two cutting edges. They
are equally inclined at 590 with the drill axis for general work.
5. Flutes
These are the helical grooves cut on the body of the drill. The function of flutes
are
1. To form the cutting edges on the point.
2. To make the chips to curl
3. To allow chips to escape
4. To allow cutting fluid to reach the cutting edge.
6. chisel edge or dead centre
This act as a flat drill. It cuts a small hole in the workpiece. Then the cutting
edges remove further material to complete the hole.
7.land
It is the narrow surface ground on the edge of the flutes. It is also called as
margin. Drill is full size only across the lands at the point end. The drill is aligned with the help
of land.
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8.Neck
It is the undercut portion between the body and the shank. Generally the size and
othe details of the drill are marked at the neck.
9. Point angle
It is the angle between the cutting edges. It is generally 1180. To cut harder
material layer angle are used
(any three)
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PART – C
17.(a) Explain the construction of double housing planner
(Diagram = 5 mark
Explanation = 5 mark)
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17.(b) Explain about the construction of shaper with neat sketch
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(Diagram = 5 mark
Explanation = 5 mark)
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18.(a) describe the various types of drilling operation
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(Diagram = 5 mark
Explanation = 5 mark)
18.(b) Briefly explain the various types of milling operation
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(Diagram = 5 mark
Explanation = 5 mark)
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19.(a) Explain surface grinding machine with neat sketch
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(Diagram = 5 mark
Explanation = 5 mark)
19.(b) Briefly explain vertical broaching operation
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(Diagram = 5 mark
Explanation = 5 mark)
20.(a) Explain the working of abrasive water jet machining
High pressurized water with abrasive particle is focused by nozzle an job and metal removal has
done. This type of process is called abrasive water jet matching.
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Main parts
1. Intersifier pump
2. Nozzle with work table movement
3. Regulating of mixing chaatimber
4. Filteration unit
Working method
The intensifier increases the water pressure and taken to the mixing chamber and mixed with
abrasive particles and also regulated and taken to nozzle to derive level of pressure as per job’s material
of derived speed of metal removal.
The very high pressurized water with abrasive particles kinetic energy is converted to pressure
energy and become stress and also metal removal takes place on work piece.
Process details
1. Work done is an the process erosion.
2. Pressure of water may be 1500 to 4000 N/m2
3. Nozzle is made by sintered diamond or tangton carbide.
4. Very hard materials also easilymachinable by this process.
(Diagram = 5 mark
Explanation = 5 mark)
20.(b) Describe working of electron beam machining
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Principle
The ions are bombard an slots surface. The bombard ion are insist atom of job to
moving.
Construction of working principle IBM
This equipment having a electron gun which is filled by argon gas. The gas molecules as
ionized by electrons. The electron gun is placed on a vaccum chamber which has argon gas.
The other names of this IBM is ion etching and ion polishing.
Advantages of EBM
1. Easy to control of metal removal rate.
2. No chemical etchant
3. No under cut
4. No need of etchant.
Advantages of EBM
1. To produce computer memories
2. To make wire dies.
3. Advantages of EBM
(Diagram = 5 mark
Explanation = 5 mark)
21.(a) Briefly explain optical measurement.
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(Diagram = 5 mark
Explanation = 5 mark)
21.(b) Explain uses of sine bar and slip gauges in angle measurement.
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(Diagram = 5 mark
Explanation = 5 mark)
PREPARED BY
K.SARAVANAPERUMAL,
LECTURER / ROBOTICS
222, APPC, PALANI