The commonly used gases in tungsten arc welding are Helium and argon
Description : For arc welding current range is usually (1) 10 to 15 A (2) 30 to 40 A (3) 50 to 100 A (4) 100 to 350 A
Last Answer : For arc welding current range is usually 100 to 350 A
Description : Identify the correct combination of respective Electric arc welding and Electric resistance welding methods : (A) Butt welding and Seam welding (B) Hydrogen shielding and Projection welding (C) Seam welding and Coated electrode welding (D) Coated electrode welding and Hydrogen shielding
Last Answer : Identify the correct combination of respective Electric arc welding and Electric resistance welding methods : (A) Butt welding and Seam welding (B) Hydrogen shielding and Projection welding ... Seam welding and Coated electrode welding (D) Coated electrode welding and Hydrogen shielding
Description : The supply for arc welding is :
Last Answer : The supply for arc welding is : Low voltage, high current ac or dc voltage
Description : Power-factor of industrial arc and induction furnace is:
Last Answer : Power-factor of industrial arc and induction furnace is: very low lagging
Description : Arc resistance (1) increases with increase in arc current (2) decrease with increase in arc current (3) is independent of arc current (4) is independent of arc length
Last Answer : Arc resistance decrease with increase in arc current
Description : The arc voltage in a circuit breaker is :
Last Answer : The arc voltage in a circuit breaker is : in phase with the arc current
Description : Electric welding equipment works best at A) Low voltage and low current B) Low Voltage and high current C) High voltage and low current D) High voltage and high current
Last Answer : Electric welding equipment works best at Low Voltage and high current
Description : In which of the following welding methods, the molten metal is poured for joining the metals ? (a) Gas welding (b) Thermit welding (c) TIG welding (d) Arc welding
Last Answer : In which of the following welding methods, the molten metal is poured for joining the metals ? (a) Gas welding (b) Thermit welding (c) TIG welding (d) Arc welding
Description : Spot welding is used for (1) Thin metal (3) Castings only (2) Rough and irregular surface (4) Thick sections
Last Answer : Spot welding is used for Thin metal
Description : The electrode rod used for welding uses a coating on it
Last Answer : The electrode rod used for welding uses a coating on it to give a vapour to serve as a shielding gas to protect the weld area from atmospheric contamination and to provide slag to protect the welded area
Description : TIG welding, thoriated tungsten electrodes are used, because it (A) Has higher current carrying capacity (B) Has better electron emissivity (C) Is stronger than ordinary tungsten (D) Is easy to prepare
Last Answer : Option B
Description : Which of the following defects is usually associated with the MAG GMAW) welding process when using Dip Transfer? a) Centerline cracking b) Lack of side wall Fusion c) Undercut d) Tungsten inclusions
Last Answer : b) Lack of side wall Fusion
Description : Argon is used in arc welding because
Last Answer : Argon is used in arc welding because A. low reactivity with metal B. ability to lower the ... of metal C. flammability D. high calorific value
Description : What type of arc welding equipment is necessary when participating in arc welding?
Last Answer : The most important equipment you can have is your safety equipment, your gloves, visor and heavy-duty clothing. You have to have some sort of a power source to generate the electricity necessary for arc welding, so I'd say a power source is your most important arc welding equipment.
Description : In arc welding, Argon is used because of its - (1) Low reactivity with metal (2) Ability to lower the melting point of the metal (3) High flammability (4) High calorific value
Last Answer : (1) Low reactivity with metal Explanation: In arc welding, Argon is used as a shielding gas because it is chemically inert and forms no compounds. At the high temperatures that welding requires, the ... to brittle welds and instability in the welding arc. So,argon and other inert gases are sprayed.
Description : The required DC voltage for arc welding is- (1) 6 to 9 V (2) 50 to 60 V (3) 200 to 250 V (4) 90 to 100 V
Last Answer : (3) 200 to 250 V
Description : Projection welding is (i) Electric arc welding (ii) Gas welding (iii)Spot welding (iv) None
Last Answer : (iv) None
Description : Which type of welding is generally used in automobile sector? a) Electric arc welding b) Electric resistance welding c) Gas welding d) Forge welding
Last Answer : b) Electric resistance welding
Description : Among gas and electric arc welding, which has the higher rate of heating? a) Gas welding b) Electric arc welding c) Gas welding and electric arc welding have equal rate of heating d) Cannot be determined
Last Answer : b) Electric arc welding
Description : Rails in the field are generally welded by using a) Thermit welding b) Gas welding c) Electric arc welding d) Forge welding
Last Answer : a) Thermit welding
Description : The electric arc welding is a type of ............. welding. (a) forge (b) fusion
Last Answer : b) fusion
Description : Thermit welding is categorised as the __________ welding. (A) Forge (B) Fusion (C) Resistance (D) Arc
Last Answer : (B) Fusion
Description : Consumable electrodes are used in the __________ welding. (A) Gas (B) Arc (C) Thermit (D) Resistance
Last Answer : (B) Arc
Description : Projection welding & stud welding is categorised as the __________ welding. (A) Pressure (B) Thermit (C) Resistance (D) Arc
Last Answer : C) Resistance
Description : Which of the following mainly decides the current to be employed is arc welding? (A) Electrode size (B) Plate thickness (C) Voltage across the arc (D) Welded portion length
Last Answer : (A) Electrode size
Description : Coating provided on the electrodes used in the arc welding is not expected to (A) Add alloying elements (B) Prevent electrode from contamination (C) Stabilise the arc (D) Provide protective atmosphere to weld
Last Answer : (B) Prevent electrode from contamination
Description : Cold cracking in the heat affected zone of a high strength steel weld can take place because of the (A) Retained austenite (B) Martensite formation (C) Relatively high sulphur content in the base metal (D) Sufficient hydrogen present in the welding arc
Last Answer : (B) Martensite formation
Description : Stainless steel is welded using (A) Oxy-acetylene flame (B) Oxy-hydrogen flame (C) Arc welding (D) Inert gas arc welding
Last Answer : (D) Inert gas arc welding
Description : When MMA welding what will be the effect on the weld f the power source was changed from AC to DC-ve? a) None b) Higher deposition rate c) It would slightly increase the depth of penetration d) The arc would become unstable
Last Answer : b) Higher deposition rate
Description : What is a typical ARC voltage setting when welding with the TIG (GTAW) process? a) 18-20V b) 24-26V c) 10-12V d) 70-90V
Last Answer : c) 10-12V
Description : A butt weld has been made by MMA in a 50mm thick impact tested steel plate. The welding electrode used was a basic type, 5mm diameter. The measured welding parameters for one of the runs was 250 amps, 24 volts, using DC ... given to calculate the arc energy b) 1.9 kJ/mm c) 1.87 kJ/mm d) 2.0 kJ/mm
Last Answer : d) 2.0 kJ/mm
Description : Explain the shielded metal arc welding (SMAW) processes with neat sketch. State its two advantages and disadvantages.
Last Answer : Working : Shielded metal arc welding uses a metallic consumable electrode of a proper composition for generating arc between itself and the parent work piece. The molten electrode metal fills the weld ... . 2. Weld may contain slag inclusions 3. Fumes make difficult the process control.
Description : List common equipments used for arc welding process.
Last Answer : 1. A.C. or D.C. machine 2. Electrode (bare or coated) 3. Electrode Holder 4. Cables and its connectors 5. Chipping Hammer 6. Earthing Clamps 7. Wire-brush 8. Helmet 9. Safety Goggles 10. Hand Gloves 11. Apron Sleeves etc.
Description : Describe the working principle of Arc Welding.
Last Answer : Arc welding is the most extensively employed method of joining metal parts. Here the source of heat is an electric arc. The arc column is generated between an anode which is the positive pole of D.C. ... also melted and is transferred in to the metal in the form of globules of molten metal.
Description : Compare resistance welding and arc welding.
Last Answer : Sr. No Resistance Welding Arc Welding 1 It is plastic welding It is fusion welding. 2 Arc is produced by heat due to resistance of flow of current by work and by application ... 8 Less skilled operator can do the job. More skilled operator is required to the job
Description : Draw a schematic of a set up of shielded metal arc welding.
Last Answer : Fig. Shielded metal arc welding set-up
Description : In arc welding, Argon is used because of its (1) Low reactivity with metal (2) Ability to lower the melting point of the metal (3) High flammability (4) High calorific value
Last Answer : Low reactivity with metal
Description : Compare between Resistance welding and Arc welding on any six points.
Last Answer : Sr.No Parameters Resistance Welding Arc Welding 1 Type of welding Plastic/Pressure/Non-fusion welding Fusion/Non pressure welding 2 Principle of heat developed Heat ... It is suitable for mass production It is suitable for heavy job, maintenance and repair work
Description : Arc welding uses following electric supply (A) ac (B) dc (C) both ac and dc (D) spiral waveform
Last Answer : both ac and dc
Description : Which of the following generators is used for DC arc welding application ? (A) Series generator (B) Shunt generator (C) Differential compound generator (D) Over -compound generator
Last Answer : A
Last Answer : The type of dc generator used for arc welding purposes is a Differentially compound generator.
Last Answer : Arc blow is a welding defect which is encountered in arc welding using a.c. current.
Description : Acetylene is commonly used in a gas welding torch. Give the molecular formula for acetylene.
Last Answer : ANSWER: C2H2 or HC2H or H2C2
Description : What are the gases used for welding?
Last Answer : The type of gaseous requirement for welding depends on the nature of welding. For example oxy-acetylene uses oxygen and acetylene, while argon is used for TIG wielding.
Description : Which gases are used for gas welding?
Last Answer : Oxygen and acetylene
Description : Gases that are commonly known as green house gases:-
Last Answer : Gases that are commonly known as green house gases:- A. `CO_(2)` and `CH_(4)` B. `NO_(2)` and CFCs C. ozone D. All the above
Description : lumen / watt is the unit of: A) light flux B) luminous intensity C) brightness D) luminous efficiency
Last Answer : luminous efficiency
Description : Which braking system on the locomotives is the costliest among the following? A) Vacuum braking on diesel locomotives B) Vacuum braking on steam locomotives C) Regenerative braking on electric locomotives D) All braking systems are equally costly
Last Answer : Which braking system on the locomotives is the costliest among the following? A) Vacuum braking on diesel locomotives B) Vacuum braking on steam locomotives C) Regenerative braking on electric locomotives D) All braking systems are equally costly
Description : In practice generative breaking is used when (a) quick motor reversal is desired. (b) load has overhauling characteristic (c) controlling elevators, rolling mills etc. (d) none of these
Last Answer : Controlling elevator , rolling mill because to stop motor some backward force required
Description : For induction heating, which of the following is abnormally high? A)Voltage B) Current C) Frequency D) Phase angle
Last Answer : For induction heating, which of the following is abnormally high? A)Voltage B) Current C) Frequency D) Phase angle