Fundamental Tricks to Solve Numericals

Q. Orthogonal turning of a mild steel tube with a tool of rake angle ${10}^{\circ }$ carried out at a feed of 0.
14 mm/rev. If the thickness of the chip produced is 0.28 mm, the values of shear angle and shear strain will be respectively

1. ${28}^{\circ }{20}^{{}^{\prime }}\text{and}2.19$
2. ${22}^{\circ }{20}^{{}^{\prime }}\text{and}3.53$
   
3. ${24}^{\circ }{30}^{{}^{\prime }}\text{and}3.53$
   
4. ${37}^{\circ }{20}^{{}^{\prime }}\text{and}5.19$

Q. The following data relate to an orthogonal turning process: back rake angle $=15deg.$ width of cut $=2mm$ chip thickness $=0.4mm$ feed rate $=0.2mm/rev$

If the cutting force and the thrust force are $900N$ and $810N$ the shear strength in $MPa$

1. $137.94$
2. $477.91$
3. $500.58$
4. $635.84$

Q. A single-point cutting tool with ${12}^o$ rake angle is used to machine a steel work-piece. The depth of cut, i.e., uncut thickness is $0.81mm$. The chip thickness under orthogonal machining condition is $1.8mm$. The shear angle is approximately.

1. ${22}^o$
2. ${26}^o$
3. ${56}^o$
4. ${76}^o$

Q. In a single point turning tool, the side rake angle and orthogonal rake angle are equal. $\varphi$ is the principal cutting edge angle and its range is $0^o\le \varphi \le {90}^o$. The chip flows in the orthogonal plane. The value of $\varphi$ is closest to

1. $0^o$
2. ${45}^o$
3. ${60}^o$
4. ${90}^o$

Q. The following data relate to an orthogonal turning process: back rake angle $=15deg.$ width of cut $=2mm$ chip thickness $=0.4mm$ feed rate $=0.2mm/rev$

The shear angle is

1. ${14}^0$
2. ${25}^0$
3. ${29}^0$
4. ${75}^0$

Q.

What does orthogonal projection means?

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.

The uncut chip thickness is

1. 0.0906
2. 0.042
3. 0.214
4. 0.1

Q. Following data correspond to an orthogonal Turning of a 100 mm diameter rod on a lathe. Rake angle: +15°; Uncut chip thickness 0.5 mm, nominal chip thickness after the cut 1.25 mm. The shear angle (in degrees) for this process is_____ (correct to two decimal places).

1. 23.32