Pick out the wrong statement. (A) Seam welding, projection welding & spot welding are the classification of electrical resistance welding (B) Electrode tip in spot welding is of copper and the tip diameter should be equal to t (where, t = plate thickness to be welded) (C) In spot welding, two pieces to be joined are overlapped and placed between two electrodes (D) Mild steel sheet cannot be spot welded

Pick out the wrong statement.
(A) Seam welding, projection welding & spot welding are the classification of electrical resistance welding
(B) Electrode tip in spot welding is of copper and the tip diameter should be
equal to t (where, t = plate thickness to be welded)
(C) In spot welding, two pieces to be joined are overlapped and placed between two electrodes
(D) Mild steel sheet cannot be spot welded
by

1 Answer

Answer :

(D) Mild steel sheet cannot be spot welded
by

Related questions

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

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

Electric resistance seam welding uses __________ electrodes. (A) Pointed (B) Disc. (C) Flat (D) Domed

Description : Electric resistance seam welding uses __________ electrodes. (A) Pointed (B) Disc. (C) Flat (D) Domed

Last Answer : Ans: B Disc type electrodes are used for electric resistance seam welding.

Electric resistance seam welding uses_______ electrodes.

Description : Electric resistance seam welding uses_______ electrodes.(A) pointed (B) disc (C) flat (D) domed

Last Answer : Electric resistance seam welding uses disc electrodes.

Chromium molybdenum steel cannot be welded using __________ welding. (A) Thermit (B) Electrical resistance (C) Oxy-acetylene (D) Any of these

Description : Chromium molybdenum steel cannot be welded using __________ welding. (A) Thermit (B) Electrical resistance (C) Oxy-acetylene (D) Any of these

Last Answer : Option B

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+ve polarity, and a ROL:of 180mm per min. What would be the arc energy? a) Insufficient information given to calculate the arc energy b) 1.9 kJ/mm c) 1.87 kJ/mm d) 2.0 kJ/mm

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

A squid axon is placed on stimulating electrodes, and an intracellular electrode is inserted and connected through a cathode-ray oscilloscope (CRO) to an indifferent electrode. When the axon is stimulated, the latent period is 1.5 ms. The intracellular electrode is 6 cm form the anode of the simulator and 4.5 cm from the cathode of the simulator. What is the conduction velocity of the axon. a. 15 m/s b. 30 m/s c. 40 m/s d. 67.5 m/s e. This cannot be determined from the information given

Description : A squid axon is placed on stimulating electrodes, and an intracellular electrode is inserted and connected through a cathode-ray oscilloscope (CRO) to an indifferent electrode. When the axon is stimulated, the latent ... . 40 m/s d. 67.5 m/s e. This cannot be determined from the information given

Last Answer : 30 m/s

Material of construction of the electrode used in the electric resistance welding is (A) Stainless steel (B) Graphite (C) Copper (D) Steel

Description : Material of construction of the electrode used in the electric resistance welding is (A) Stainless steel (B) Graphite (C) Copper (D) Steel

Last Answer : Option C

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

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

When welding medium carbon steel plates over 100mm in thickness would the basic electrodes require any pre treatment before use? a) None if they were in a vacuum pack opened 8 hours prior to use b) None if they were in a sealed vacuum pack prior to use c) Heat to 500 °C for 2 hours if used outside d) Baked at 150°C for 4hours prior to use

Description : When welding medium carbon steel plates over 100mm in thickness would the basic electrodes require any pre treatment before use? a) None if they were in a vacuum pack opened 8 hours prior to use b) None if ... ) Heat to 500 °C for 2 hours if used outside d) Baked at 150°C for 4hours prior to use

Last Answer : b) None if they were in a sealed vacuum pack prior to use

Describe with neat sketch: (i) Spot Welding (ii)Seam Welding

Description : Describe with neat sketch: (i) Spot Welding (ii)Seam Welding

Last Answer : (i) Spot Welding: Spot welding is employed to join overlapping strips, sheets or plates of metal at small areas .The pieces are assembled between two electrodes, which must possess high electrical & ... used to conserve the electrodes and cool the work rapidly to speed up the operation.   

State four advantages of seam welding over spot welding.

Description : State four advantages of seam welding over spot welding.

Last Answer : Advantages of seam welding over spot welding:- 1. Due to seam welding we get continuous weld which is air-tight 2. Gas tight as well as liquid tight joints can be made. 3. The Overlap is ... . The production of single seam weld and parallel seams can be got simultaneously. 5. Efficient energy use.

In electrical resistance welding, distortion results from the use of improper (A) Clamping methods (B) Electrodes (C) Current (D) Filler material

Description : In electrical resistance welding, distortion results from the use of improper (A) Clamping methods (B) Electrodes (C) Current (D) Filler material

Last Answer : (A) Clamping methods

Double full fillet welded joint cannot be used for a plate thickness greater than i. 1/8” ii. 3/8” iii. 5/8” iv. None

Description : Double full fillet welded joint cannot be used for a plate thickness greater than i. 1/8” ii. 3/8” iii. 5/8” iv. None

Last Answer : iii. 5/8”

Single full fillet welded joint cannot be used for a plate thickness greater than i. 1/8” ii. 2/8” iii. 3/8” iv. None

Description : Single full fillet welded joint cannot be used for a plate thickness greater than i. 1/8” ii. 2/8” iii. 3/8” iv. None

Last Answer : iii. 3/8”

Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In small columns, local efficiency is larger than Murphree efficiency; in large columns local efficiency is smaller than Murphree efficiency (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s (D) The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s

The maximum thickness of the metal which can be welded using ultrasonic welding is __________ mm. (A) 0.5 (B) 3 (C) 10 (D) 25

Description : The maximum thickness of the metal which can be welded using ultrasonic welding is __________ mm. (A) 0.5 (B) 3 (C) 10 (D) 25

Last Answer : (B) 3

Pick out the wrong statement. (A) Wrought iron contains about 0.02% carbon (B) Wrought iron cannot be easily forged and welded (C) The chilled cast iron does not contain graphite (D) Spheroidal grey cast iron contains graphite flakes

Description : Pick out the wrong statement. (A) Wrought iron contains about 0.02% carbon (B) Wrought iron cannot be easily forged and welded (C) The chilled cast iron does not contain graphite (D) Spheroidal grey cast iron contains graphite flakes

Last Answer : (B) Wrought iron cannot be easily forged and welded

Describe with neat sketch operation of seam type resistance welding.

Description : Describe with neat sketch operation of seam type resistance welding.

Last Answer : 1) Seam Welding its neat labelled sketch:  Explanation: Seam welding is nothing but series of continuous spot welding Working: Job is kept in between two electrodes under ... reached supply is cut down and external pressure is applied simultaneously across the job to complete weld.  

Oxygen cylinders used for autogenous (cutting/welding) purposes are (A) Seamless & made of steel (B) Heat treated before use (C) Made by sand casting (D) Welded steel cylinders

Description : Oxygen cylinders used for autogenous (cutting/welding) purposes are (A) Seamless & made of steel (B) Heat treated before use (C) Made by sand casting (D) Welded steel cylinders

Last Answer : Option A

Pick out the wrong statement. (A) Packed towers are preferred for vacuum operation, because the pressure drop through the packing is less and they (packings) also lessen the possibility of tower wall collapse (B) Packed towers are preferred over plate towers for handling corrosive and foamy liquids (C) Diameter of randomly packed tower is normally more than 1.2 metres (D) Due to uneven supply and improper distribution of liquid, problem of channelling, loading & flooding is generally encountered in packed towers

Description : Pick out the wrong statement. (A) Packed towers are preferred for vacuum operation, because the pressure drop through the packing is less and they (packings) also lessen the ... of liquid, problem of channelling, loading & flooding is generally encountered in packed towers

Last Answer : (C) Diameter of randomly packed tower is normally more than 1.2 metres

Projection welding is (i) Electric arc welding (ii) Gas welding (iii)Spot welding (iv) None

Description : Projection welding is (i) Electric arc welding (ii) Gas welding (iii)Spot welding (iv) None

Last Answer : (iv) None

Projection welding & stud welding is categorised as the __________ welding. (A) Pressure (B) Thermit (C) Resistance (D) Arc

Description : Projection welding & stud welding is categorised as the __________ welding. (A) Pressure (B) Thermit (C) Resistance (D) Arc

Last Answer : C) Resistance

Larger length & diameter water pipes are made by (A) Electrical resistance welding (B) Die casting (C) Semi-centrifugal casting (D) Continuous casting

Description : Larger length & diameter water pipes are made by (A) Electrical resistance welding (B) Die casting (C) Semi-centrifugal casting (D) Continuous casting

Last Answer : options A

Larger length & diameter water pipes are made by (A) Electrical resistance welding (B) Die casting (C) Semi-centrifugal casting (D) Continuous casting

Description : Larger length & diameter water pipes are made by (A) Electrical resistance welding (B) Die casting (C) Semi-centrifugal casting (D) Continuous casting

Last Answer : Option C

Pick out the wrong statement. (A) Alloys are harder than their component elements (B) Presence of silicon in steel decreases its electrical resistance (C) Karbate is an acid resistant material of construction (D) Nichrome, a steel alloyed with 10% Ni and 20% Cr can be used upto a temperature of 1100°C

Description : Pick out the wrong statement. (A) Alloys are harder than their component elements (B) Presence of silicon in steel decreases its electrical resistance (C) Karbate is an acid resistant material of construction ... , a steel alloyed with 10% Ni and 20% Cr can be used upto a temperature of 1100°C

Last Answer : (B) Presence of silicon in steel decreases its electrical resistance

Consumable electrodes are used in the __________ welding. (A) Gas (B) Arc (C) Thermit (D) Resistance

Description : Consumable electrodes are used in the __________ welding. (A) Gas (B) Arc (C) Thermit (D) Resistance

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Pick up the incorrect statement (A) The cross-sectional area of the welded member is effective (B) A welded joint develops strength of its parent metal (C) Welded joints provide rigidity (D) Welding takes more time than riveting

Description : Pick up the incorrect statement (A) The cross-sectional area of the welded member is effective (B) A welded joint develops strength of its parent metal (C) Welded joints provide rigidity (D) Welding takes more time than riveting

Last Answer : (D) Welding takes more time than riveting

The allowable shear stress in the web of mild steel beams decreases with (a) Decrease in h/t ratio (b) Increase in h/t ratio (c ) Decrease in thickness (d) Increase in height Where h is the height and t is the thickness

Description : The allowable shear stress in the web of mild steel beams decreases with (a) Decrease in h/t ratio (b) Increase in h/t ratio (c ) Decrease in thickness (d) Increase in height Where h is the height and t is the thickness

Last Answer : (b) Increase in h/t ratio

Stainless steel is welded using (A) Oxy-acetylene flame (B) Oxy-hydrogen flame (C) Arc welding (D) Inert gas arc welding

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

Pick out the wrong statement about cavitation. (A) Sudden reduction of pressure in a fluid flow system caused by flow separation, vortex formation or abrupt closing of valve leads to cavitation (B) Cavitation may be caused due to boiling of liquid by decreasing the pressure resulting in formation & collapse of vapor cavities (C) Cavitation begins at higher static pressure and lower velocity in larger diameter pipelines resulting in audible noise(D) Large scale cavitation cannot damage pipeline, restrict fluid flow anddamage steam turbine blades

Description : Pick out the wrong statement about cavitation. (A) Sudden reduction of pressure in a fluid flow system caused by flow separation, vortex formation or abrupt closing of valve leads to cavitation ... (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades

Last Answer : (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades

In resistance welding the electrodes used are of

Last Answer : In resistance welding the electrodes used are of Non – Consumable type

belt of silk runs over two metal pulleys, one of which is surrounded by a hollow metal sphere. Two electrodes, in the form of comb-shaped rows of sharp metal points, are positioned respectively near to the bottom of the lower pulley and inside the sphere, over the upper pulley. The top electrode is connected to the sphere and the bottom one to the ground. A high DC potential is applied to the upper pulley. A simple version of which equipment is being described here?

Description : belt of silk runs over two metal pulleys, one of which is surrounded by a hollow metal sphere. Two electrodes, in the form of comb-shaped rows of sharp metal points, are positioned ... potential is applied to the upper pulley. A simple version of which equipment is being described here?

Last Answer : Van de Graaff generator.

Q-9 how many electrodes are used in the TANDEM SAW? What is the polarity of the both electrode?

Description : Q-9 how many electrodes are used in the TANDEM SAW? What is the polarity of the both electrode?

Last Answer : In TANDEM SAW process there are more than one electrode is used. But for first electrode alternative current and for second electrode direct current shall be used.

Pick out the wrong statement. (A) Reciprocal of the resistance to heat flow is called thermal conductance (B) Unit of thermal conductance is W/°K (C) Thermal conductance of a wall of thickness 'L', thermal conductivity 'k' and heat flow area 'A' is kL/A (D) None of these

Description : Pick out the wrong statement. (A) Reciprocal of the resistance to heat flow is called thermal conductance (B) Unit of thermal conductance is W/°K (C) Thermal conductance of a wall of thickness 'L', thermal conductivity 'k' and heat flow area 'A' is kL/A (D) None of these

Last Answer : (C) Thermal conductance of a wall of thickness 'L', thermal conductivity 'k' and heat flow area 'A' is kL/A

Out of the following, the __________ pipe has the least corrosion resistance. (A) Mild steel (B) Copper (C) Cast iron (D) Wrought iron

Description : Out of the following, the __________ pipe has the least corrosion resistance. (A) Mild steel (B) Copper (C) Cast iron (D) Wrought iron

Last Answer : D) Wrought iron

According to Unwin's formula, the diameter of a rivet of plate of thickness is : (A) d = 6.05 t (B) d = 1.5 t + 4 (C) d = t(D) d = t + 1.5

Description : According to Unwin's formula, the diameter of a rivet of plate of thickness is :  (A) d = 6.05 t (B) d = 1.5 t + 4  (C) d = t (D) d = t + 1.5 

Last Answer : (A) d = 6.05 t

The maximum longitudinal pitch in bolted joints, subjected to tensile forces, wherein t = thickness of the plate and D = diameter of bolt, is (a) 32 D (b) 16 D (c) 32 t (d) 16 t

Description : The maximum longitudinal pitch in bolted joints, subjected to tensile forces, wherein t = thickness of the plate and D = diameter of bolt, is (a) 32 D (b) 16 D (c) 32 t (d) 16 t

Last Answer : (d) 16 t

Explain seam welding process with the help of neat sketch.

Description : Explain seam welding process with the help of neat sketch.

Last Answer : Seam Welding is a Resistance Welding (RW) process used for producing continuous joint of overlapping sheets by passing them between two rotating electrode wheels. Heat generated by the electric current flowing through ... the electrodes and cool the work rapidly to speed up the operation.    

List applications of seam welding.

Description : List applications of seam welding.

Last Answer : Seam welding is used to produce leak proof joint required in 1. Small Tanks, 2. Boilers 3. Containers, 4. Radiators 5. Heat Exchangers etc.

Three materials A, B and C of equal thickness and of thermal conductivity of 20, 40 & 60 kcal/hr. m. °C respectively are joined together. The temperature outside of A and C are 30°C and 100°C respectively. The interface between B and C will be at a temperature of __________ °C. (A) 40 (B) 95 (C) 70 (D) 50

Description : Three materials A, B and C of equal thickness and of thermal conductivity of 20, 40 & 60 kcal/hr. m. °C respectively are joined together. The temperature outside of A and C are 30°C and 100°C respectively. The interface ... C will be at a temperature of __________ °C. (A) 40 (B) 95 (C) 70 (D) 50

Last Answer : (C) 70

Pick out the wrong statement. (A) Different solids have different equilibrium moisture curves (B) Total condenser or reboiler is considered equivalent to one theoretical plate in McCabe-Thiele method of theoretical plate calculation for distillation column (C) Heat removal load on cooler remains constant, even with increase of the reflux ratio in a distillation column (D) Even a forced draft cooling tower cannot cool water below the wet bulb temperature

Description : Pick out the wrong statement. (A) Different solids have different equilibrium moisture curves (B) Total condenser or reboiler is considered equivalent to one theoretical plate in McCabe-Thiele method of ... (D) Even a forced draft cooling tower cannot cool water below the wet bulb temperature

Last Answer : (C) Heat removal load on cooler remains constant, even with increase of the reflux ratio in a distillation column

Rails used for A T Welding shall not normally be welded? (i) 20 years old . (ii) 30 years old (iii) 40 years old (iv) 50 years old*

Description : Rails used for A T Welding shall not normally be welded? (i) 20 years old . (ii) 30 years old (iii) 40 years old (iv) 50 years old*

Last Answer : iv) 50 years old*

Pick out the wrong statement. (A) Longer tubes are less expensive per unit heat transfer area as compared to shorter tubes (B) A cost index is merely a number for a given year showing the cost at that time relative to a certain base year (C) Turnover ratio of a chemical plant is the ratio of gross annual sales to the fixed capital investment (D) Plates with butt welded joints are less expensive compared to lap welded joints, because squaring of plates is not necessary

Description : Pick out the wrong statement. (A) Longer tubes are less expensive per unit heat transfer area as compared to shorter tubes (B) A cost index is merely a number for a given year ... butt welded joints are less expensive compared to lap welded joints, because squaring of plates is not necessary

Last Answer : (D) Plates with butt welded joints are less expensive compared to lap welded joints, because squaring of plates is not necessary

Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point (C) Each ton of petroleum oil on distillation produces about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil

Description : Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches ... about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil

Last Answer : (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point

Oxyacetylene reducing flame is used while carrying out welding on (A) Alloy steel (B) Grey cast iron (C) Mild steel (D) High carbon steel

Description : Oxyacetylene reducing flame is used while carrying out welding on (A) Alloy steel (B) Grey cast iron (C) Mild steel (D) High carbon steel

Last Answer : (C) Mild steel

Oxyacetylene reducing flame is used while carrying out welding on (A) Alloy steel (B) Grey cast iron (C) Mild steel (D) High carbon steel

Description : Oxyacetylene reducing flame is used while carrying out welding on (A) Alloy steel (B) Grey cast iron (C) Mild steel (D) High carbon steel

Last Answer : Option C

A reinforced concrete cantilever porch has thickness t. The main reinforcing steel will be placed (a) At mid-thickness (b) At t/3 from the top (c) Close to the bottom surface (d) Close to the top surface

Description : A reinforced concrete cantilever porch has thickness t. The main reinforcing steel will be placed (a) At mid-thickness (b) At t/3 from the top (c) Close to the bottom surface (d) Close to the top surface

Last Answer : (d) Close to the top surface

Pick out the wrong statement (A) Low ozone layer thickness in polar regions is due to cold climatic conditions (B) Amount of unburnt hydrocarbons emitted by two stroke petrol engine is more as compared to that emitted by a four stroke engine (C) Carbon monoxide present in the two stroke petrol engine exhaust is much less as compared to that emitted from a four stroke engine (D) Mercury as a pollutant can enter the blood stream & the digestive system/ lungs and is responsible for causing Minamata disease

Description : Pick out the wrong statement (A) Low ozone layer thickness in polar regions is due to cold climatic conditions (B) Amount of unburnt hydrocarbons emitted by two stroke petrol engine is more ... can enter the blood stream & the digestive system/ lungs and is responsible for causing Minamata disease

Last Answer : (D) Mercury as a pollutant can enter the blood stream & the digestive system/ lungs and is responsible for causing Minamata disease

Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads (D) Fanning friction factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Description : Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres ( ... factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Last Answer : (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads