B.Tech
(SEM.6th )Examination ,2008-09
ADVANCE WELDING TECHNOLOGY
NOTE:- 1.Attempt all five questions.
2.all questions carry equal marks\
3.be precise in your answer
Question no.-1 write short note on any four of the following:
(a)explosive welding
(b)modes of metal transfer
(c)hardfacing
(d)ultrasonic welding
(e)TIG vs MIG
(f)soldering and brazing
Question no.-2-write any two of the following:
(a)what is the schaeffler diagram? how it can be used for the selection of electrodes?
(b)explain the principle of electron beam welding with a neat sketch.what is the mechanism of high carbon peetration ?what do you understand by work accelerated and self accelerated electron gun?
(c)explain the laser beam welding with the help of diagram.what is the principle of laser generation ?
Question no.-3-answer any two of the following:
(a)what do you mean by underwater welding ?describe in brief.how may arc stability could be improved in it? what are the advantages and limitations of wet under water welding ?
(b)what is the principle behind ultrasonic welding ?describe ultrasonic welding with a neat sketch.
(c)what is metallising process ?how the surface of work must be prepared for this process also describe the nature of bond between sprayed metal and work.
Question no.-4- -answer any two of the following:
(a)briefly describe the neat sketches the procedure commenly followed for the welding of pipelines on site .what is stove pipe technique or welding pipelines ?
(b)what are the similarities and differences between casting of metals and fusion welds?
(c)explain in brief the various defects and distortions in welding.
Question no.5-answer any two of the following:
(a)define weldability of materials and mention the factors on which weldability depends.
(b)what is weld decay ?how can weld decay be avoided?
(c)what are the characterstics of HAZ ? also explain the factors affecting HAZ.
B.Tech
(SEM.6th )Examination ,2007-08
ADVANCE WELDING TECHNOLOGY
NOTE:- 1.Attempt all five questions.
2.all questions carry equal marks\
3.be precise in your answer
Question no.-1 write short note on any four of the following:
(a)electron beam welding
(b)arc blow in welding
(c)spray welding
(d)importance of schaeffler diagram
(e) electroslag welding
(f)under water welding
(g)life prediction of welded structures
Question no.2.answer any two of the following:
(a)what do you understand by polarity in welding .compare DC welding with AC welding .which polarity will you select while welding (1)aluminium (2)copper?what are the forces acting which transfer the metal from the metal electrode to the work piece in course of welding ?
(b)what do you understand by friction welding ?where is it suitable?discuss its principle .what are the diffrences amongst the homogeneous ,autogeneous and heterogeneous process?give example of each process.
(c)what do you understand by resistance welding ?what s the spot welding and how it defers from the projection welding ?what is to be done to join different thickness of same metals by spot welding?what must be done to joint same thickness of different metals?
Question no.3-answer any two of the following:
(a)describe with the sketches ,the mechanism of explosive welding.also briefly write about weld interface and welding parameters .what are the applications of the explosive welding ?
(b)what is meant by hard facing ?how hard facing with electrical arc is theoretically considered as simultaneous alloy steel making in electrical arc furnace and heat treatment ?what welding process may be used for hard facing ?enumerate the advantages and applications of the hardfacing.
(c)explain the terms transferred mode and non transferred modes used in plasma arc welding .what is plasma?describe plasma acr weldimg and mention its advantages .
Question no.4-answer any two of the following:
(a)whats is meant by weld quality ?discuss the factors that influence it.
(b)explain why some joints may have to be preheated prior to welding?
(c)list the rules that must be followed to avoid cracking in welded joints.
Question no.5-answer any two of the following:
(a)define weldability .discuss the weldability if carbon metals and explain why some metals are easier to weld than others .cast iron is generally difficult to weld .why?how does the weldability of steel changes as its carbon content increases ?
(b)describe the reasons that fatigue failures heat generally occurs in HAZ of welds instead of through the weld bead itself.
(c)define theoretical/empirical/semi-empirical approach for temperature distribution in welding.also ,draw temperature contours around the weld of arc during arc welding.
NOTE:- these questions are important for sessional tests as well as university point of view .the questions written in red colour are most important for the 1st sessional test
(SEM.6th )Examination ,2008-09
ADVANCE WELDING TECHNOLOGY
NOTE:- 1.Attempt all five questions.
2.all questions carry equal marks\
3.be precise in your answer
Question no.-1 write short note on any four of the following:
(a)explosive welding
(b)modes of metal transfer
(c)hardfacing
(d)ultrasonic welding
(e)TIG vs MIG
(f)soldering and brazing
Question no.-2-write any two of the following:
(a)what is the schaeffler diagram? how it can be used for the selection of electrodes?
(b)explain the principle of electron beam welding with a neat sketch.what is the mechanism of high carbon peetration ?what do you understand by work accelerated and self accelerated electron gun?
(c)explain the laser beam welding with the help of diagram.what is the principle of laser generation ?
Question no.-3-answer any two of the following:
(a)what do you mean by underwater welding ?describe in brief.how may arc stability could be improved in it? what are the advantages and limitations of wet under water welding ?
(b)what is the principle behind ultrasonic welding ?describe ultrasonic welding with a neat sketch.
(c)what is metallising process ?how the surface of work must be prepared for this process also describe the nature of bond between sprayed metal and work.
Question no.-4- -answer any two of the following:
(a)briefly describe the neat sketches the procedure commenly followed for the welding of pipelines on site .what is stove pipe technique or welding pipelines ?
(b)what are the similarities and differences between casting of metals and fusion welds?
(c)explain in brief the various defects and distortions in welding.
Question no.5-answer any two of the following:
(a)define weldability of materials and mention the factors on which weldability depends.
(b)what is weld decay ?how can weld decay be avoided?
(c)what are the characterstics of HAZ ? also explain the factors affecting HAZ.
B.Tech
(SEM.6th )Examination ,2007-08
ADVANCE WELDING TECHNOLOGY
NOTE:- 1.Attempt all five questions.
2.all questions carry equal marks\
3.be precise in your answer
Question no.-1 write short note on any four of the following:
(a)electron beam welding
(b)arc blow in welding
(c)spray welding
(d)importance of schaeffler diagram
(e) electroslag welding
(f)under water welding
(g)life prediction of welded structures
Question no.2.answer any two of the following:
(a)what do you understand by polarity in welding .compare DC welding with AC welding .which polarity will you select while welding (1)aluminium (2)copper?what are the forces acting which transfer the metal from the metal electrode to the work piece in course of welding ?
(b)what do you understand by friction welding ?where is it suitable?discuss its principle .what are the diffrences amongst the homogeneous ,autogeneous and heterogeneous process?give example of each process.
(c)what do you understand by resistance welding ?what s the spot welding and how it defers from the projection welding ?what is to be done to join different thickness of same metals by spot welding?what must be done to joint same thickness of different metals?
Question no.3-answer any two of the following:
(a)describe with the sketches ,the mechanism of explosive welding.also briefly write about weld interface and welding parameters .what are the applications of the explosive welding ?
(b)what is meant by hard facing ?how hard facing with electrical arc is theoretically considered as simultaneous alloy steel making in electrical arc furnace and heat treatment ?what welding process may be used for hard facing ?enumerate the advantages and applications of the hardfacing.
(c)explain the terms transferred mode and non transferred modes used in plasma arc welding .what is plasma?describe plasma acr weldimg and mention its advantages .
Question no.4-answer any two of the following:
(a)whats is meant by weld quality ?discuss the factors that influence it.
(b)explain why some joints may have to be preheated prior to welding?
(c)list the rules that must be followed to avoid cracking in welded joints.
Question no.5-answer any two of the following:
(a)define weldability .discuss the weldability if carbon metals and explain why some metals are easier to weld than others .cast iron is generally difficult to weld .why?how does the weldability of steel changes as its carbon content increases ?
(b)describe the reasons that fatigue failures heat generally occurs in HAZ of welds instead of through the weld bead itself.
(c)define theoretical/empirical/semi-empirical approach for temperature distribution in welding.also ,draw temperature contours around the weld of arc during arc welding.
NOTE:- these questions are important for sessional tests as well as university point of view .the questions written in red colour are most important for the 1st sessional test
