Analysis of Orthogonal Machining

Q. During orthogonal cutting of $MS$ with a $10deg$ rake angle tool, the chip thickness ratio was obtained as $0.4$. The shear angle (in degrees) evaluated from this data is

1. $6.53$
2. $20.22$
3. $22.94$
4. $50.00$

Q. For an orthogonal cutting operation, tool material is HSS, rake angle is 22°, chip thickness is 0.8 mm, speed is 48 m/min and red is 0.4 mm/rev. The shear plane angle (in degrees) is

1. 19.24
2. 29.70
3. 56.00
4. 68.75

Q. In orthogonal turning of a low carbon steel bar of diameter $150mm$ uncoated carbide tool the cutting velocity is $90m/min$. The feed is $0.24mm/rev$ and the depth of cut is $2mm$. The chip thickness obtained is $0.48mm$. If the orthogonal rake angle is zero and the principal cutting edge angle is ${90}^o$, the shear angle in degree is

1. $20.56$
2. $26.56$
3. $30.56$
4. $36.56$

Q. In an orthogonal machining operation,
if U = specific cutting energy, $\beta =$ friction angle, $\varphi =$ shear plane angle, $\alpha =$ Tool rake angle, then the shear stress $\left(\tau \right)$ will be expressed as:

1. $\frac{U\sin \varphi \cos (\beta -\alpha )}{\cos (\varphi +\beta -\alpha )}$
2. $\frac{U\cos \alpha \cos (\varphi +\beta -\alpha )}{\cos (\beta -\alpha )}$
3. $\frac{U\sin \varphi \cos (\varphi +\beta -\alpha )}{\cos (\beta -\alpha )}$
4. $\frac{U\sin \alpha \cos (\varphi -\alpha )}{\cos (\beta -\alpha )}$

Q. In turning trail using orthogonal cutting, a chip length of 84mm was obtained for uncut chip length of 200 mm. The cutting conditions were:
$V_c=30$ m/min, uncut chip thickness is 0.5 mm, rake angle is ${20}^{\circ }$, width of cut is 2 mm, cutting force is 900 N, and cutting tool is HSS.

The coefficient of friction, if the machining is taking place under Lee and Shaffer shear angle conditions, is

1. 0.42
2. 0.46
3. 0.847
4. 1.16

Q. In orthogonal machining operation, the chip thickness and the uncut chip thickness are equal to $0.45mm$. If the tool rake and is $0$ deg. The shear plane angle is

1. ${45}^o$
2. ${30}^o$
3. ${18}^o$
4. ${60}^o$

Q. Assertion (A): The ratio of uncut chip thickness to actual chip thickness is always less than one and is termed as cutting ratio in orthogonal cutting.
Reason (R): The frictional force is very high due to the occurrence of sticking friction rather than sliding friction.

1. Both $A$ and $R$ are true and $R$ is the correct explanation of $A$
2. Both $A$ and $R$ are true but $R$ is not a correct explanation of $A$
3. $A$ is true but $R$ is false
4. $A$ is false but $R$ is true

Q. During an orthogonal machining operating on mild steel, the following results are obtained:
Uncut chip thickness = 0.3 mm
Chip thickness = 0.9 mm
Rake angle = 0°
Cutting force = 900 N
Thrust force = 400 N
Ultimate shear stress of the work materials = 380 $N/m{m}^2$
The minimum shear plane area is

1. 1.914 $m{m}^2$
2. 2.628 $m{m}^2$
3. 3.828 $m{m}^2$
4. 4.029 $m{m}^2$

Q. A bar of 75 mm diameter is machined to reduce its diameter by orthogonal cutting. If the length of the cut chip is 73.5 mm and rake angle is ${15}^{\circ },$ the shear plane angle is

1. ${16}^{\circ }$
2. ${18}^{\circ }$
3. ${23}^{\circ }$
4. ${29}^{\circ }$

Q. In an orthogonal machining operation, the cutting and thrust forces are 600 N and 173 N respectively. If the value of shear angle is ${60}^{\circ }$, what is the approximate value of shear force?

1. 100 N
2. 150 N
3. 200 N
4. 300 N

Q. Turning is done using a tool of 5-5-8-8-8-25-0.1 mm, geometry, with a feed of 0.1 mm/stroke and depth of cut of 2 mm.

If shear angle is ${30}^{\circ }$, the plan area of cut in $m{m}^2$ is

1. 0.4
2. 0.3
3. 0.2
4. 0.1

Q. During orthogonal machining on a work piece of diameter 100 mm, the length of chip produced is 78.5 mm. The chip reduction coefficient is

1. 2.5
2. 4
3. 0.25
4. 0.4

Q.

Common Data:
In an orthogonal machining operation:
Uncut thickness $=0.5mm$
Cutting speed $=20m/min$
Rake angle $={15}^o$
Width of cut $=5mm$
Chip thickness $=07mm$
Thrust force $=200N$
Cutting force $=1200N$
Assume Merchant's theory.

The coefficient of friction at the tool-chip interface is

1. $0.23$
2. $0.46$
3. $0.85$
4. $0.95$

Q. A bar of 75 mm diameter is machined to reduce its diameter by orthogonal cutting. If the length of the cut chip is 73.5 mm and rake angle is ${15}^{\circ }$, the shear plane angle is

1. ${16}^{\circ }$
2. ${18}^{\circ }$
3. ${23}^{\circ }$
4. ${29}^{\circ }$

Q. During orthogonal machining on a work piece of diameter 100 mm, the length of the chip produced is 78.5 mm. The chip reduction coefficient is

1. 2.5
2. 4
3. 0.25
4. 0.4

Q. Turning is done using a tool of 5 - 5 - 8 - 8 - 8 - 25 - 0.1 mm, geometry, with a feed of 0.1 mm/stroke and depth of cut of 2 mm.

If shear angle is ${30}^{\circ }$, the plan area of cut in $m{m}^2$ is

1. 0.4
2. 0.3
3. 0.2
4. 0.1