1. What is the value of stand-off distance in Water jet machining?
a) 0.1 – 1 mm
b) 1 – 2 mm
c) 2 – 6 mm
d) 6 – 14 mm
Explanation: Stand-off distance value ranges between 2.5 – 6 mm in Water jet machining.
2. What are the values of jet velocities in Water jet machining?
a) 100 – 200 m/s
b) 200 – 500 m/s
c) 500 – 1500 m/s
d) 1500 – 3000 m/s
Explanation: Velocity of the water jet stream ranges between 540 – 1480 m/s in WJM
3. State whether the following statement is true or false.
“As the pump pressure increases, depth of cut decreases in Water jet machining.”
a) True
b) False
Explanation: As the pump pressure is increases, the depth of cut also increases in WJM.
4. What is the value of material thickness of work piece in WJM?
a) 0.001 – 0.25 mm
b) 0.8 – 25 mm
c) 50 – 100 mm
d) 100 – 500 mm
Explanation: The material thickness value of work piece range between 0.8 – 25 mm.
5. What is the value of feed rate in Water Jet Machining?
a) 0.0001 – 0.025 m/min
b) 0.05 – 0.25 m/min
c) 0.5 – 200 m/min
d) 200 – 500 m/min
Explanation: In Water jet machining, value of the feed rate ranges between 0.5 – 200 m/min.
6. In WJM, what are the properties of jet fluid that affect the MRR?
a) Velocity
b) Flow rate
c) Viscosity
d) All of the mentioned
Explanation: All the mentioned properties above, of jet fluid affect the MRR in Water jet machining.
7. Which of the following property/ies of nozzle does not affect the material removal rate in Water jet machining?
a) Material
b) Diameter
c) Outside temperature
d) Stand-off distance
Explanation: In the nozzle, outside temperature has no effect on the rate of material removal.
8. In how many directions, can the cutting takes place in Water jet machining?
a) Uni-directional
b) Bi-directional
c) Multi-directional
d) None of the mentioned
Explanation: Water jet machining has multi directional cutting capacity i.e.., in any direction in three dimensional space.
9. In Water jet machining, cuts can be started at which place of workpiece?
a) From left
b) From right
c) From middle
d) From any point
Explanation: In WJM, cuts can be started from any point on the workpiece
10. State whether the following statement is true or false.
“To start the cuts in Water jet machining, pre-drilled holes are not necessary.”
a) True
b) False
Explanation: In Water jet machining, we need not require any pre-drilled holes to start the cuts.