1
GATE PI 1990
+5
-1.5
A parting tool has a ground front clearance angle of $${6^0}$$ and the back rake angle of $${10^0}$$. The tool, by mistake, was set $$1.5$$ $$mm$$ above the line of centers while machining a job of $$50$$ $$mm$$ out-side diameter.

The diameter of the job at which, while parting, the tool will start rubbing

A
$$35mm$$
B
$$28.7mm$$
C
$$57.4mm$$
D
none
2
GATE PI 1990
Subjective
+5
-0
The following data apply to machining a part on turret lathe and a general purpose lathe The setup cost and the cost for special tooling on the turret lathe would be $$Rs.3000/-.$$ These costs are negligible on the general purpose lathe. Calculate the batch seize which justifies the use of turret lathe.

3
GATE PI 1989
Subjective
+5
-0
Calculate the tonnage capacity of the broaching machine required to broach on the hole under the following conditions.
Diameter of the finished hole $$=75mm,$$
rise per tooth $$=0.03mm$$
Tooth pitch $$=10mm,$$
Length of the broach $$=750mm$$
Cutting speed $$=6m/min,$$
specific cutting pressure $$= 1300 \times {t^{0.4}}\,\,N/m{m^2},$$ (Where $$t$$ is the uncut chip thickness)
If the tool and work handling time is $$0.5min,$$ estimate the production rate per hour
4
GATE PI 1989
Subjective
+5
-0
The results of machining steel with $$2$$ grades of tool material are given below. For a $$180$$ $$min.$$ Tool life which tool is recommended and why? If the tool regrinding and changing time is $$15min,$$ the cutting speed for tool $$A$$ $$ahs$$ to be chosen ($$40m/min$$ or $$50m/min$$)

GATE PI Subjects
Fluid Mechanics
Metrology
Theory of Machines
Engineering Mathematics
Heat Transfer
Machine Tools and Machining
Industrial Engineering
Engineering Mechanics
Strength of Materials
Thermodynamics
Machine Design
Casting
Joining of Materials
Metal Forming
EXAM MAP
Joint Entrance Examination