Marks 1
In gas tungsten arc welding process, the material coated on pure tungsten electrode to enhance its current carrying capacity is
Brazing and soldering are
Which of the following welding process results in the smallest heat affected zone
In resistance seam welding, the electrode is in the form of a
The current in Amperes used in resistance spot welding of plain carbon steel sheets ($$1$$ to $$3$$ $$mm$$ thick) lies within the range:
The metal powder used in Thermit welding of steel is:
High speed electron beam welding is focused on the weld spot using
In resistance welding, heat is generated due to the resistance between
Which of the following powders should be fed for effective oxy-fuel cutting of stainless steel
The consumption of an oxy-acetylene flame for cutting of steel contains more oxygen
The composition of an oxy-acetylene flame for cutting of steel contain more oxygen.
The joint configuration best suited for adhesive bonding is
The type of coated electrode most widely used for welding low carbon steel is
Filler material is ......... A...... in resistance welding and the heat generated in the process is directly proportional to ........ B.........
(A)....
Continuous rails for Indian railways are welded by ........ Welding process.
High alloy steel components are preheated before welding for reducing
In spot welding of aluminium sheets, the welding current should be .........A........ and weld time should be kept ............B......... than for $$M...
....................... is the non-fusion method of joining dissimilar metals with metals whose melting temp is greater than $${400^ \circ }C$$.
With increasing joint thickness, the tensile strength of a brazed joint
...
The mode of metal transfer in $$C{O_2}$$-$$MIG$$ welding at low temperature is
In $$TIG$$ welding a ...........A. .......... and ..........B.......... electrode is used.
A. non-consumable / consumable
B. coated / bare ...
In welding brass with oxy-acetylene flame, the type of flame used is
Marks 2
In linear gas tungsten arc welding of two plates of the same material, the peak temperature $$T$$ (in $$K$$) is given as ܶ$$T = {{{c_1}q} \over \alpha...
Two flat steel sheets, each of $$2.5$$ $$mm$$ thickness, are being resistance spot welded using a current of $$6000$$ $$A$$ and weld time of $$0.2$$ $...
Two aluminium alloy plates each $$10$$ $$mm$$ thick and $$1$$ $$m$$ long are welded without crowning by multipass tungsten inert gas butt welding. The...
In an arc welding operation carried out with a power source maintained at $$40$$ volts and $$400$$ amperes, the consumable electrode melts and just fi...
In a $$DC$$ $$arc$$ welding operating, the length characteristic was obtained as $${V_{arc}} = 20 + 5l$$ where the $$arc$$ length $$l$$ was varied bet...
During a steady gas metal arc welding with direct current electrode positive polarity, the welding current, voltage and weld speed are $$150A,$$ $$30V...
Autogeneous gas tungsten arc welding of a steel plate is carried out with welding current of $$500A,$$ voltage of $$20V,$$ and weld speed of $$20mm/mi...
Two pipes of inner diameter $$100mm$$ and outer diameter $$110mm$$ each are joined by flash butt welding using $$30V$$ power supply. At the interface,...
Aluminium strips of $$2mm$$ thickness are joined together by resistance spot welding process by applying an electric current $$6000$$$$A$$ for $$0.15s...
Which of the following powders should be fed for effective oxy-fuel cutting of stainless steel
Which pair among the following solid state welding processes uses heat from an external source
$$P$$- Diffusion welding
$$Q$$- Friction welding
$$R$$-...
The $$DC$$ power source for arc welding has the characteristic $$3V + 1 = 240,$$ where $$V=$$ Voltage and $${\rm I}\,\, = $$ current in amp. For maxim...
Two $$8$$ $$mm$$ thick steel plates are placed $$5$$ $$mm$$ apart and welded by a butt joint. Welding is carried out at $$20$$ $$V$$ and speed of $$5$...
Match List - I (welding problems) with List - II (Causes) and select the correct answer using the codes given below the lists:
...
Consider the following statements:
The size of the heat affected zone (HAZ) will increase with
$$1.$$ increased starting temperature
$$2.$$ increase...
Consider the following statements :
The magnitude of residual stresses in welding depends upon
$$1.$$ Metal melted / deposited
$$2.$$ Design of weld...
In a fabrication shop, a $$T$$-joint is to be made between two plates using a chain intermittent, double fillet weld of $$6$$ $$mm$$ leg length. The i...
A $$900$$ $$mm$$ long steel plate is welded by manual metal arc welding process using welding current of $$150$$ $$A,$$ arc voltage of $$20$$ $$V$$ an...
The cold cracking susceptibility of the heat affected zone in an arc weld is influenced by
$$P.$$ Entraped hydrogen,
$$Q.$$ Residual stresses
$$R.$$ ...
Which of the following process can be used for welding of Aluminium alloys
$$P.$$ Submerged arc welding
$$Q.$$ Gas metal arc welding
$$R.$$ Electrosl...
Match List - I (welding defects) with List - II (causes) and select the correct answer using the codes given below the lists
...
...
In spot pulsed laser welding of aluminium plates (density $$ = 2700kg/{m^3},$$ specific heat $$=896J/kg,$$ melting temp $$=933K,$$ latent heat of melt...
During gas welding of copper sheets a neutral flame was used consuming $$8$$ liters of acetylene. But the weld was found to be defective. So it was re...
...
In welding process, penetration is increased by
In welding a mild steel sheet using an oxy-acetylene flame, the total amount of acetylene consumed was $$8.0$$ liters the oxygen consumption from the ...
Match the following
...
Marks 5
Resistance spot welding of two steel sheets is carried out in lap joint configuration by using a welding current of $$3$$ $$KA$$ and a weld time of $$...
Resistance spot welding of two steel sheets is carried out in lap joint configuration by using a welding current of $$3$$ $$KA$$ and a weld time of $$...
A weld is made using $$MIG$$ welding process with the following welding parameters: Current: $$200A;$$ Voltage: $$25V;$$ Welding speed: $$18$$ $$cm/mi...
A weld is made using $$MIG$$ welding process with the following welding parameters: Current: $$200A;$$ Voltage: $$25V;$$ Welding speed: $$18$$ $$cm/mi...
A weld is made using $$MIG$$ welding process with the following welding parameters: Current: $$200A;$$ Voltage: $$25V;$$ Welding speed: $$18$$ $$cm/mi...
A weld is made using $$MIG$$ welding process with the following welding parameters: Current: $$200A;$$ Voltage: $$25V;$$ Welding speed: $$18$$ $$cm/mi...
Two plates with symmetrical $$V$$ joint penetration of $$V$$ angle $$60deg$$ are to be arc welded in a single pass. The power $$P(kW)$$-arc length $$L...
The voltage-arc length characteristics of a power source is $$V=20+40L,$$ where $$V=$$ operating voltage in volts and $$L=$$ arc length in $$cm.$$ The...
Two sheets of low carbon steel $$1.5mm$$ thick each are spot welded by passing a current $$10000$$ amps for $$5$$ cycles in $$50$$ $$Hz$$ main supply....
In $$MIG$$ welding the power source characteristics is $${V_p} = 36 - {\rm I}/60$$ and the arc characteristics is $${V_a} = 2{L_a}\,\,\,\, + 27.$$ Fin...
A resistance welder is rated at $$50$$ $$kVA,$$ at $$50\% $$ duty cycle. Secondary voltage is always constant at $$25$$ volts. If a job requires $$150...
The voltage-arc length characteristic of a $$DC$$ arc is given by $$V=20+40L.$$ where $$L=$$ arc length in $$cm.$$ The power source characteristics ca...