Production

Q. A through hole is drilled in an aluminum alloy plate of 15 mm thickness with a drill bit of diameter 10 mm, at a feed of 0.25 mm/rev and spindle speed of 1200 rpm. If the specific energy required for cutting this material is 0.7 $N-m/m{m}^3$, the power required is_____(round off to two decimal places).

1. 274.89

Q. A metal cutting test was conducted on a lathe and the following were noted:
Vertical force on the tool = 2000 N
depth of cut = 2.00 mm
Feed = 5 cuts/mm
Pressure of the chip cross-sectional area on the tools is______ $kN/m{m}^2$

1. 5

Q. A through hole is drilled in an aluminum alloy plate of 15 mm thickness with a drill bit of diameter 10 mm, at a feed of 0.25 mm/rev and spindle speed of 1200 rpm. If the specific energy required for cutting this material is 0.7 $N-m/m{m}^3$, the power required is (round off to two decimal places).

Q. When the depth of cut is increased, the specific cutting energy

1. Increases
2. Decreases
3. Remains same
4. Reaches an optimum value

Q. In orthogonal turning of medium carbon steel, the specific machining energy is $2.J/m{m}^3$. The cutting velocity, feed and depth of cut are $120m/min,0.2mm/rev$ and $2mm$ respectively. The main cutting force in $N$ is

1. $40$
2. $80$
3. $400$
4. $800$

Q. The main cutting force acting on a tool during the turning (orthogonal cutting) operation of metal is $400N$. The turning was performed using $2mm$ depth of cut and $0.1mm/rev$ feed rate. The specific cutting pressure (in $N/m{m}^2$) is

1. $1000$
2. $2000$
3. $3000$
4. $4000$

Q. Machinability of steels is improved by the addition of

1. Sulphur
2. Silicon
3. Phosphorous
4. All of the above

Q. Pure metal poses a machinability problem in turning operations. The reason is the

1. Increased length of contact due to the production of continuous chip
2. Susceptibility to chemical reactions
3. Tendency to from intense adhesion joint with tool face
4. Absence of inclusions which aids chip formation

Q. $\text{The bending force required for a 1.5 mm thick steel (having ultimate tensile strength 800 MPa) sheet of 1 m length to be bent in a wiping die (K = 0.33) is kN. The die radius used is 3 mm. (By using the governing equation = bending force,}{F}_b=\frac{kL\sigma t^2}{W})\text{Every symbol has their using meaning.}$

1. 79.2

Q. A metal sheet is to be bent at an angle of ${57.3}^o$ with a bend radius of 120 mm and the bend allowance for stretch factor 0.6 is 12.3 cm. The thickness of metal is ________ cm. (correct upto one decimal place)

1. 0.05