1
GATE ME 2012
MCQ (Single Correct Answer)
+2
-0.6
In a $$DC$$ $$arc$$ welding operating, the length characteristic was obtained as $${V_{arc}} = 20 + 5l$$ where the $$arc$$ length $$l$$ was varied between $$5mm$$ and $$7mm.$$ Here $${V_{arc}}$$ denotes the arc voltage in volts. The $$arc$$ current was varied from $$400A$$ to $$500A.$$ Assuming linear power source characteristic, the open circuit voltage and the short circuit current for the welding operation are
2
GATE ME 2010
MCQ (Single Correct Answer)
+2
-0.6
Two steel bars each of diameter $$10mm$$ are coaxially friction welded end to end at an axial pressure of $$200MPa$$ and rotational speed of $$400rpm$$. The coefficient of friction between the mating faces of the rotating bars is $$0.50.$$ The torque is assumed to act at the $$3/{4^{th}}$$ radius of the rotating bar. The power (in $$kW$$) consumed at the interface of the welding is
3
GATE ME 2008
MCQ (Single Correct Answer)
+2
-0.6
In arc welding of a butt joint, the welding speed is to be selected such that highest cooling rate is achieved. Melting efficiency and heat transfer efficiency are $$0.5$$ and $$0.7$$, respectively. The area of the weld cross section is $$5$$ $$m{m^2}$$ and the unit energy required to melt the metal is $$10\,\,J/m{m^3},$$ if the welding power is $$2$$ $$kW,$$ the welding speed in $$mm/s$$ is closet to
4
GATE ME 2007
MCQ (Single Correct Answer)
+2
-0.6
Two metallic sheets, each of $$2.0$$ $$mm$$ thickness are welded in lap joint configuration by resistance spot welding at a welding current of $$10$$ $$KA$$ and welding time of $$10$$ milliseconds. A spherical fusion zone extending up to the full thickness of each sheet is formed. The properties of the metallic sheets are given below:
Ambient temp $$=293$$ $$K$$
Melting point temp $$=1793$$ $$K$$
Density $$ = 7000kg/{m^3}$$
Latent heat of fusion $$=300$$ $$kJ/kg$$
Specific heat $$=800$$ $$J/kgK$$
Ambient temp $$=293$$ $$K$$
Melting point temp $$=1793$$ $$K$$
Density $$ = 7000kg/{m^3}$$
Latent heat of fusion $$=300$$ $$kJ/kg$$
Specific heat $$=800$$ $$J/kgK$$
Assume:
(i) Contact resistance along sheet - sheet interface is $$500$$ micro-ohm and along
$$\,\,\,\,\,\,$$electrode-sheet interface is zero.:
(ii) No conductive heat loss through the bulk sheet material; and
(iii) The complete weld fusion zone is at the melting temperature, the melting
$$\,\,\,\,\,\,\,\,\,$$efficiency (in %) of the process is .........
Questions Asked from Welding Process (Marks 2)
Number in Brackets after Paper Indicates No. of Questions
GATE ME 2024 (1)
GATE ME 2022 Set 2 (1)
GATE ME 2022 Set 1 (1)
GATE ME 2016 Set 2 (1)
GATE ME 2016 Set 3 (1)
GATE ME 2015 Set 2 (1)
GATE ME 2015 Set 1 (1)
GATE ME 2014 Set 4 (1)
GATE ME 2014 Set 3 (1)
GATE ME 2012 (1)
GATE ME 2010 (1)
GATE ME 2008 (1)
GATE ME 2007 (2)
GATE ME 2006 (1)
GATE ME 2005 (1)
GATE ME 2004 (1)
GATE ME 2003 (1)
GATE ME 2001 (1)
GATE ME 1996 (1)
GATE ME 1991 (1)
GATE ME Subjects
Engineering Mechanics
Machine Design
Strength of Materials
Heat Transfer
Production Engineering
Industrial Engineering
Turbo Machinery
Theory of Machines
Engineering Mathematics
Fluid Mechanics
Thermodynamics
General Aptitude