RRB JE Mechanical- Welding Questionbank 3

Mechanical-Engineering

Gas flame cutting cut mild steel successfully upto thickness —-? (BMRCL JE 24 Feb.2019)

• 10mm to 50mm
• 1mm to 100mm
• 150mm to 1000mm
• 0.5mm to 2000mm

Explanation:

• Gas flame can cut mild steel from 0.5mm to 2000mm thickness. Metal can be cut in any shape both internally and externally.

Which of the following is the methods of gas flame cutting? (RRB Allahabad JE 19.12.2010)

• Oxy-acetylene cutting
• Semi automatic and automatic flame cutting
• Oxy-fuel gas cutting
• All of these

Explanation:

• All three methods – Oxy-acetylene cutting, semi-automatic/automatic flame cutting, and oxy-fuel gas cutting – are methods of gas flame cutting.

Which of the following is the principle of Oxy-acetylene gas cutting? (RRB Mumbai JE 05.10.2008)

• Burning of hot metal by oxygen gas jet
• Cut hot metal by vaporization
• Both (a) and (b)
• None of these

Explanation:

• In oxy-acetylene gas cutting, the metal is heated below its melting point. A jet of pure oxygen is released from the nozzle at the hot spot, causing the metal to burn without melting.

Which of the following not a part of cutting torch? (RRB Mumbai JE 19.12.2010)

• Handle
• Hose pipe nipples
• Electrode
• Injector

Explanation:

• The electrode is not a part of the cutting torch. Its main parts are handle, hose pipe nipples, and injector.

What makes acetylene gas when mixed with air? (DMRC JE 2013)

• Explosive mixture
• Idle mixture
• Impartial mixture
• None of these

Explanation:

• Acetylene gas combines with air to form an explosive mixture. That’s why acetylene is kept dissolved with acetone and slowly released with a nozzle to get the flame from the mixture of oxygen and acetylene.

Which of the following gases is used to produce safety in gases of atmospheric to hot workpiece and welding bead? (Konkan Railway STA 2017)

• Helium
• Argon
• Both (a) and (b)
• None of these

Explanation:

• In TIG and MIG welding, inert gases like Argon and Helium cover the arc and weld pool to protect the weld metal from atmospheric gases like oxygen and nitrogen.

Which of the following gases is used for increases reactivity of welding? (Konkan Railway SSE 2015)

• Shielding gas
• Active gas
• Fuel gas
• All of the above

Explanation:

• Active gas is used to increase the reactivity of welding. Carbon dioxide is an active gas used to increase reactivity.

Which gas is made when calcium carbide mixture with wet of air? (RRB Chandigarh SSE 25.10.2009)

• C2H2
• N2
• H2
• CO2

Explanation:

• Calcium carbide reacts with moisture in the air to form acetylene gas (C2H2). CaC2 + 2H2O → C2H2 + 2CaO.

Flame cut operation may during welding increase the likelihood of —-? (RRB Mumbai C&G JE 25.10.2009)

• Cracking
• Misalignment problems
• Inclusions
• All of these

Explanation:

• Flame cut operation may increase the possibility of misalignment problems, inclusions, and cracking during welding.

Oxy-pressure and nozzle size in flame cutting would influence —-? (RRB Gorakhpur RDSO SSE 25.10.2009)

• The temperature required for cut initiation
• Ability to cut stainless steels
• The depth of cut obtainable
• None of these

Explanation:

• Oxy-pressure and nozzle size affect the depth of cut in flame cutting.

Which are two elements in acetylene gas? (RRB Jammu JE 25.10.2009)

• Carbon and hydrogen
• Calcium and hydrogen
• Calcium and chlorine
• Carbon and chlorine

Explanation:

• Acetylene gas (C2H2) contains carbon and hydrogen. It is the best fuel gas for welding.

Acetylene is stored in gas cylinders to kept in liquid form its liquid of name is? (RRB Malda SSE 25.10.2009)

• NH3
• Petroleum
• Water
• Acetone

Explanation:

• Acetylene is stored in gas cylinders in liquid form dissolved in acetone. Acetone is also effective as a cleaning agent for removing grease and oil.

What is retard gas? (RRB Allahabad JE 25.10.2009)

• Mixture of flammable gas
• Result of reaction from water of oxygen H2
• Result of reaction from water of CaC2
• None of the above

Explanation:

• Retort gas is a mixture of flammable gas.

Which of the following purified material in first chamber in purification of acetylene gas? (RRB Mumbai C&G SSE 25.10.2009)

• Purified material
• Lime stone
• Filter wool
• Water

Explanation:

• In the purification of acetylene gas, limestone is used as a purifying material in the first chamber.

Acetylene gas can be dissolved in —-? (RRB Patna JE 25.10.2009)

• Water
• Kerosene
• Acetone
• All of these

Explanation:

• Acetylene can be dissolved in acetone with high pressure for safe storage and use.

Which part in flame maximum temperature takes place? (RRB Bhopal TM SSE 25.10.2009)

• Inner cone
• Middle part
• Outer part
• None of these

Explanation:

• The maximum flame temperature occurs at the inner cone. Neutral flame: 3100°C, Carburizing: 2900°C, Oxidizing: 3300°C.

Which of the following reason is mostly used for Oxy-acetylene flame? (RRB Allahabad SSE 09.09.2012)

• It is available easily
• It gives maximum temperature
• It is very low cost
• It is no loss

Explanation:

• Oxy-acetylene flame is very cheap, effective for gas welding, and usually portable. It is easy to operate and does not require a highly skilled operator.

Which material of welding is done by neutral flame? (RRB Banglore SSE 09.09.2012)

• Of mild steel
• Of stainless steel
• Of copper
• All of these

Explanation:

• Neutral flame causes no chemical change in the weld metal. Metals like mild steel, stainless steel, cast iron, and aluminium can be welded with it.

Which steel is used for neutral flame? (RRB Kolkata SSE 09.09.2012)

• High carbon steel
• Mild steel
• Low carbon steel
• All type of steel

Explanation:

• Neutral flame is obtained by supplying equal volumes of oxygen and acetylene. It is used for welding high carbon steel, mild steel, low carbon steel, cast iron, copper, and aluminium.

Which temperature of neutral flame? (RRB Gorakhpur Design SSE 09.09.2012)

• 3460°C
• 3260°C
• 3160°C
• 3060°C

Explanation:

• Neutral flame has approximately equal amounts of acetylene and oxygen. Its temperature is around 3260°C.

Which of the following flame is right for preheating of cutting? (RRB Bhopal SSE 09.09.2012)

• O flame
• Neutral flame
• Light carburizing flame
• Carburizing flame

Explanation:

• Neutral flame is used for most welding operations and for preheating during cutting operations. Preheating is necessary when welding cast iron workpieces.

The Oxy-acetylene flame is used —-? (RRB Chandigarh SSE 09.09.2012)

• In welding of ferrous material
• In welding of non-ferrous material
• In cutting
• All of these

Explanation:

• Oxy-acetylene flame is used for welding and cutting of both ferrous and non-ferrous materials because the temperature of this flame is high.

What is the differential character of carburizing flame? (RRB Jammu SSE 09.09.2012)

• Two internal flame cone and one outer part
• Two flame cone and one outer part
• Short yellow flame and outer part
• Long yellow smooth flame part

Explanation:

• Carburizing flame (also called reducing flame) has more acetylene than oxygen. It has three cones: inner cone, intermediate flame cone, and outer envelope. It is recognized by the acetylene feather between the inner core and outer envelope.

Which of the following flame has maximum temperature? (RRB Allahabad JE 09.09.2012)

• Neutral flame
• Oxidizing flame
• Carburizing flame
• Soft flame

Explanation:

• Oxidizing flame has higher oxygen content than acetylene, resulting in complete combustion and higher temperature (about 3500°C).

Velocity of soft flame is —-? (RRB Bhubneshwar JE II 29.11.2008)

• 10 to 20 m/s
• 10 to 15 m/s
• 10 to 25 m/s
• 10 to 40 m/s

Explanation:

• The velocity of soft flame is 10-15 m/s in cutting flame.

Which flame is used for most work? (JMRC JE 10.06.2017)

• Neutral flame
• Oxidizing flame
• Carburizing flame
• Soft flame

Explanation:

• Neutral flame is most frequently used, containing equal amounts of oxygen and acetylene.

Which of the following flame is impossible to use in welding? (RRB Bhubneshwar JE II 19.12.2010)

• Soft flame
• Neutral flame
• Detonation flame
• Tough flame

Explanation:

• Detonation flame is impossible to use in welding due to its higher velocity.

The flame away from tip can be improved by —-? (RRB Allahabad SSE 19.12.2010)

• Reducing the pressure of gas
• Whole of nozzle done clean
• Cold of torch
• Reducing the volume of O2

Explanation:

• When the flame starts moving away from the tip, it is corrected by reducing the gas pressure.

Under this defect, instead of burning above the flame tip, it burns ahead of the tip. This statement is related to which of the following defects? (RRB Mumbai SSE 05.10.2008)

• Pumping
• Change the shape of Flame
• Vibration of Flame
• Frequent breakdown of flame

Explanation:

• When the flame does not burn above the tip and burns beyond the tip, this defect occurs due to frequent discontinuity of the flame. It is caused by high pressure of the gas supply.

Which is a type of oxy-acetylene cutting? (RRB Mumbai SSE 19.12.2010)

• Gas cutting
• Electric cutting
• Both (a) and (b)
• None of these

Explanation:

• Oxy-acetylene cutting is a type of gas cutting.

Which of the following in this torch is a part of extra valve? (RRB Mumbai SSE 19.12.2010)

• Welding torch
• Cutting torch
• Both (a) and (b)
• None of these

Explanation:

• A cutting torch has additional valves: cutting oxygen valve, acetylene valve, and needle valve.

Which of the following is not standard of oxy-acetylene cutting? (RRB Kolkata Diesel JE 25.10.2009)

• Conductor
• Flame temperature
• Metal of nozzle
• Made of flame

Explanation:

• Material of the nozzle is not a standard parameter. Nozzles can be made of various metals.

Which is normal method to cutting of mild steel? (RRB Mumbai C&G JE 25.10.2009)

• Oxy-acetylene cutting
• Oxy-hydrogen cutting
• Oxy-propan cutting
• All of the above

Explanation:

• The most common method of cutting mild steel is oxy-acetylene cutting, using a neutral flame.

Which of the following materials is best cut by oxy-cutting process? (RRB Jammu JE 25.10.2009)

• brass
• copper
• stainless steel
• mild steel

Explanation:

• Mild steel is best cut by the oxy-cutting process because it oxidizes faster compared to other metals.

Oxy-acetylene flame cuts metal by its —-? (RRB Allahabad JE 25.10.2009)

• evaporation
• oxidation
• burning
• intensive oxidation

Explanation:

• Oxy-acetylene flame cuts metal by intensive oxidation. It is used for welding steel, cast iron, metal sheets, and for metal cutting.

In gas welding the combustion takes place by mixing oxygen with —-? (RRB Patna JE 25.10.2009)

• hydrogen
• fuel gas
• CO
• CO2

Explanation:

• Combustion in gas welding takes place through a mixture of oxygen and fuel gases like acetylene.

Which of the following advantages of flame cutting? (RRB Allahabad SSE 09.09.2012)

• Effective and low cost
• Cut metals in two small shapes
• All of these
• Pierce slots and holes of different size

Explanation:

• Flame cutting can cut metals into small shapes difficult for other methods. Equipment is portable and can be used for field work. Multiple torches can cut multiple pieces simultaneously.

Which of the following limitation of gas cutting? (RRB Kolkata SSE 09.09.2012)

• Cutting steel and cast iron only
• Dimensional tolerances are poor
• Hazards to plant and workers
• All of the above

Explanation:

• Gas cutting limitations include: only steel and cast iron can be cut, poor dimensional tolerances, hazards to plant and workers, less suitable for stainless steel and aluminium, and noise when cutting thick sections.

Flame cutting also known as —-? (RRB Bhopal SSE 09.09.2012)

• Oxy acetylene cutting
• Oxy fuel gas cutting
• Oxygen burning
• All of these

Explanation:

• Flame cutting is also known as oxy-acetylene cutting, oxy-fuel gas cutting, or oxygen burning. It can cut 0.5mm to 2000mm thick metal.

Fuel cutting process is —-? (RRB Jammu SSE 09.09.2012)

• Chemical process
• Thermo chemical process
• Electro chemical process
• Gas diffusion process

Explanation:

• Fuel cutting process is a thermo-chemical process using acetylene and oxygen as gas welding fuel. Metal can be cut in any shape.

In flame cutting which flame is used? (RRB Bhubneshwar JE II 29.11.2008)

• Carburizing flame
• Oxidizing flame
• Neutral flame
• All of these

Explanation:

• In flame cutting, metal is cut by an oxidizing flame.

In the method, a large amount of solder is melted in a tank that is closed. RRB JE (Re-Exam) 04.06.2025

• Dip soldering
• Flame soldering
• Infrared soldering
• Soldering iron

Explanation:

• In dip soldering, a large amount of solder is melted in a closed tank. Objects are dipped into the molten solder bath for joining.

Brazing is a process of metals without melting the base metal. RRB JE Stage 2 (22.04.2025 9:00 AM-11:00 AM)

• Joining
• Melting
• Drilling
• Cutting

Explanation:

• Brazing is a metal-joining process where filler metal is heated above its melting point and distributed between close-fitting parts by capillary action. The base metals are not melted.

Soldering is a similar or dissimilar metals by heating them to a required temperature. RRB JE Stage 2 (22.04.2025 9:00 AM-11:00 AM)

• method of cutting
• method of boring
• method of joining
• method of cooling

Explanation:

• Soldering is a metal joining process where similar or dissimilar metals are joined by melting a filler metal (solder) with a lower melting point than the base metals.

In torch brazing, heat is produced by burning a mixture of —-? RRB JE Stage 2 (22.04.2025 9:00 AM-11:00 AM)

• oxy-hydrogen gas
• oxy-acetylene gas
• oxy-nitrogen gas
• oxy-neon gas

Explanation:

• In torch brazing, heat is produced by burning a mixture of oxy-acetylene gas.

In brazing, the filler metal is drawn into the joint by means of —-? RRB JE Stage 2 (22.04.2025 2:30-4:30 PM)

• friction
• damping action
• surface tension
• capillary action

Explanation:

• Both brazing and soldering use capillary action to draw filler metal into the joint. In brazing, filler metal melting temperature is above 420°C; in soldering, it is below 420°C.

The filler metal used in brazing has a melting point of above —-? RRB JE 30-08-2019

• 300°C
• 200°C
• 520°C
• 420°C

Explanation:

• Brazing uses filler metal whose melting temperature is above 420°C (450°C) but below the melting point of the metals being joined.

Soft solder consists of —-? RRB JE 31-08-2019

• Lead and tin
• Lead and zinc
• Lead and aluminum
• Copper and tin

Explanation:

• Soft solder consists of lead and tin. The most widely used solder contains 60% Pb and 40% Sn.

The commonly used flux for brazing is —-? (DMRC JE 22.09.2017) (DMRC JE 2013)

• Borax
• NH4Cl
• Resin
• Inert gas

Explanation:

• Borax is the commonly used flux in brazing. Flux melts to give protective gases which protect molten metal from atmospheric oxygen and nitrogen.

Solder is an alloy of —-? (BMRC JE 24 Feb.2019)

• Tin and silver
• Copper and tin
• Tin and lead
• Lead and copper

Explanation:

• Solder is an alloy of lead and tin. Electronic components are generally joined by soldering at temperatures below 450°C.

During soldering —-? (RRB Allahabad JE 19.12.2010)

• arc is produced between solder iron and metal to be soldered
• solder iron bit is red hot
• joint area must be clean and close fitting
• metal is heated from top as well as bottom

Explanation:

• The joint area should be clean and close fitting during soldering. Soft solder is melted and applied to the joint.

Which one of the following is not a fusion welding process? (RRB JE (Shift-3), 28.08.2015)

• Gas welding
• Arc welding
• Brazing
• Resistance welding

Explanation:

• Brazing is not a fusion welding process because only the filler metal melts, not the base metal. Fusion welding involves melting the base metals together.

In braze welding, the filler metal is —-? (RRB Mumbai JE 05.10.2008)

• Distributed by capillary attraction
• Melted and deposited at the point where the weld is to be made
• Both A and B
• Not required

Explanation:

• In braze welding, filler metal is melted and deposited at the weld point and moves between surfaces by capillary attraction, making connections upon cooling.

Binding wire used to support the joints for soldering is made of —-? (RRB Mumbai JE 19.12.2010)

• aluminum
• copper
• soft iron
• mild steel

Explanation:

• Binding wire used to support joints in soldering is made of soft iron.

The soldering process is carried out in temperature range —-? (RRB Chandigarh SSE 25.10.2009) (DMRC JE 2013)

• 70-150°C
• 15-60°C
• 180-250°C
• 300-500°C

Explanation:

• Soldering is carried out in the temperature range of 180°C-250°C using zinc chloride, sodium chloride, or resins as flux.

The melting point of the filler metal in brazing should be above —-? (RRB Jammu JE 25.10.2009)

• 420°C
• 600°C
• 1530°C
• 800°C

Explanation:

• In brazing, the filler metal melting point should be above 420°C, varying according to the filler metal components.

Which of the following brazing joints is strongest? (RRB Allahabad JE 25.10.2009)

• Butt
• Scarf (inclined)
• Lap
• All are equally strong

Explanation:

• In brazing, a butt joint (face-to-face) is stronger than other types of joints, with efficiency of 70 to 80%.

The purpose of using flux in soldering is to —-? (RRB Patna JE 25.10.2009)

• increase fluidity of solder metal
• prevent oxides formation
• wash away the surplus solder
• lowering the melting temperature of solder

Explanation:

• Flux in soldering prevents formation of oxide layers on the joint, removes impurities, and reduces surface tension of solder.

Electronic components are often joined by —-? (RRB Allahabad SSE 09.09.2012)

• adhesive
• soldering
• brazing
• welding

Explanation:

• Electronic components are often joined by soldering.

Solder is an alloy of —-? (RRB Kolkata SSE 09.09.2012)

• Copper & Tin
• Lead & Tin
• Lead & Copper
• Copper & aluminium

Explanation:

• Solder is an alloy of lead and tin. Types include mild solder (40% Pb + 60% Sn), medium (50%+50%), plumber (70%+30%), and electrician (60%+40%).

The Soldering Iron is heated in a gas flame until —-? (RRB Bhopal SSE 09.09.2012)

• the coating of Borax on the bit turns black
• the gas flame appears orange in the colour
• the gas flame appears green in the colour
• the bit is red hot

Explanation:

• For soldering, the soldering iron is heated until the gas flame becomes green.

What is the method for joining two similar or dissimilar metals using a special fusible alloy? (RRB Jammu SSE 09.09.2012)

• Brazing
• Soldering
• Arc welding
• None of these

Explanation:

• Joining similar or dissimilar metals using a special fusible alloy is called brazing. Speller is an alloy of copper and zinc with melting point about 600°C.

The temperature employed in brazing are —-? (RRB Bhubneshwar JE II 29.11.2008)

• below the melting point of the metals to be joined
• above the melting point of the metals to be joined
• below the melting point of the filler metal
• same as those employed in soldering

Explanation:

• Brazing and soldering are done below the melting point of the metals to be joined.

What is lack of fusion in welding defects? RRB JE (Re-Exam) 04.06.2025

• It is the entrapment of slag or other impurities in the weld
• It is the failure of the filler metal to fuse with the parent metal
• It is the failure of the filler metal to penetrate into the welding joint
• It is a group of small holes throughout the weld metal

Explanation:

• Lack of fusion is the failure of the filler metal to fuse with the parent metal.

Blowholes are welding defects caused by —-? RRB JE (Re-Exam) 04.06.2025

• unsuitable parent metals used in the weld
• gas being trapped and due to moisture
• poor edge preparation
• too great a heat concentration

Explanation:

• Blowholes are caused by gas being trapped due to moisture. Undercut is a groove along the weld bead edge. Burn through occurs when weld metal penetrates through base metal.

What is lack of penetration in welding defects? RRB JE (Re-Exam) 04.06.2025

• Small holes throughout the weld metal
• Failure of the filler metal to fuse with the parent metal
• Cracks either in the weld metal or in the parent metal
• Failure of the filler metal to penetrate into the root of the joint

Explanation:

• Lack of penetration is the failure of filler metal to penetrate into the root of the joint.

Slag inclusion is the welding defect caused by —-? RRB JE Stage 2 (22.04.2025 2:30-4:30 PM)

• insufficient cleaning and preparation of the base metal before welding commences
• incorrect edge penetration
• gas being trapped, due to moisture
• contamination of either the filler or parent metals

Explanation:

• Slag inclusion is caused by trapping of non-metallic solid particles (oxide fluxes of electrode coating) in the weld metal due to improper welding techniques or inadequate cleaning.

____ is a welding defect caused by trapping of gas during the welding process. RRB JE Stage 2 (22.04.2025 2:30-4:30 PM)

• Undercut
• Burn through
• Porosity
• Cracking

Explanation:

• Porosity is a welding defect caused by trapping of gas within the weld metal, resulting in voids or pores.

____ is a group of fine holes on the surface of the weld caused by gas entrapment. RRB JE 31-08-2019

• Gas pocket
• Porosity
• Blow holes
• Crack

Explanation:

• Porosity is a group of small voids on or just below the weld surface, formed due to trapping of atmospheric gases in the liquid metal.

Slag inclusion defined as a welding defect is due to —-? (DMRC JE 22.09.2017)

• poor joint selection
• arc blow
• improper cleaning of the work piece
• damp electrode

Explanation:

• Slag inclusion is due to improper cleaning of the work piece. Arc blow occurs in DC welding causing porosity on the weld surface.

Arc blow is a welding defect which is encountered —-? (JMRC JE 10.06.2017)

• in arc welding using AC current
• in arc welding using DC current
• in gas welding
• in thermit welding

Explanation:

• Arc blow occurs when the arc deviates from its path, mostly in DC welding. Disadvantages include more spattering, porous welding beads, and deficiency in fusion.

Which of the following is not a fusion welding process? (BMRCL JE 24 Feb. 2019)

• Arc welding
• Resistance welding
• Gas welding
• Friction stir welding

Explanation:

• Arc welding, gas welding, electro slag welding, and electron beam welding are fusion welding processes. Friction stir welding is a solid-state welding process that does not use filler material.

Which of the following is not a cause of weld spatter? (RRB Bhubaneshwar JE-11 19.12.2010)

• Wrong polarity
• Presence of surface contaminants
• High welding current
• Quality of consumables

Explanation:

• Wrong polarity is not a cause of weld spatter. Spattering occurs when weld bead pellets stick around the job due to various reasons.

Weld spatter is a —-? (RRB Allahabad JE 19.12.2010)

• flux
• electrode coating
• welding defect
• welding test

Explanation:

• Weld spatter is a welding defect. Common welding defects include hot cracking, cold cracking, slag inclusion, weld spatter, and undercuts.

Penetration in case of gas metal arc welding is about —-? (RRB Allahabad SSE 19.12.2010)

• 3.5
• 5
• 1.25
• 15

Explanation:

• In gas metal arc welding, penetration depth is 1 to 1.5 times the electrode diameter (D).

Too high welding current in arc welding would result in —-? (RRB Mumbai JE 05.10.2008)

• Excessive spatter, under cutting along edges, irregular deposits, wasted electrodes
• Excessive piling up of weld metal, poor penetration, wasted electrodes
• too small bead, weak weld and wasted electrodes
• excessive piling up of weld metal, overlapping without penetration of edges, wasted electrodes

Explanation:

• High welding current results in excessive spatter, poor appearance, irregular metal deposition, and wasted electrodes.

Preheating of work piece is essential in welding —-? (RRB JE Bhopal Paper-I (Shift-II), 28.08.2015) (SSC JE Online Exam 02.03.2017, 10 am) SSC JE 22 Jan 2018 (Morning)

• High speed steel
• Stainless steel
• Cast iron
• Aluminium

Explanation:

• Preheating of cast iron is essential in welding due to high carbon percentage causing internal stress during direct welding.

Welding spatter is —-? (RRB JE (Shift-I), 27.08.2015) (ISRO-2012)

• welding defect
• flux
• electrode coating
• welding technique

Explanation:

• Weld spatter is a welding defect where filler metal is sprayed around the job surface as small balls due to high welding current.

Match List-I (Welding Defects) with List-II (Causes) (RRB Mumbai SSE 05.10.2008)

• A-2, B-4, C-3, D-1
• A-4, B-2, C-1, D-3
• A-2, B-4, C-1, D-3
• A-2, B-4, C-3, D-1

Explanation:

• Spatter is caused by arc blow (A-2). Distortion is caused by poor joint selection (B-4). Slag inclusion is caused by improper cleaning in multi-pass welding (C-3). Porosity is caused by damp electrodes (D-1).

Weld spatter is a welding defect due to —-? (RRB JE (Shift-III), 27.08.2015)

• Lack of flux
• High welding current
• High welding speed
• Dirty metal surface

Explanation:

• Weld spatter is due to high welding current. It increases electrode consumption. Causes include improper cleaning, long arc, high voltage/current, moisture in flux, and arc blow.

Preheating before welding is done to —-? (RRB Mumbai JE 19.12.2010)

• Make the steel softer
• Burn away oil, grease etc. from the plate surfaces
• Prevent cold cracks
• Prevent plate distortion

Explanation:

• Preheating before welding is done to prevent cold cracks.

The phenomenon of weld decay occurs in —-? (UPRVUNL JE 2015), (SSC JE 2010) (RRB JE Bhopal Paper II (Shift-II) 26.08.2015)

• Cast iron
• Brass
• Bronze
• Stainless steel

Explanation:

• Weld decay/corrosion occurs in stainless steel when chromium oxide forms on the surface due to atmospheric oxygen, preventing oxidation and consuming more electrodes.

Distortion in welding occurs due to —-? (RRB Mumbai SSE 19.12.2010)

• Oxidation of weld pool
• Improper clamping methods
• High current
• Use of wrong electrodes

Explanation:

• Distortion occurs due to improper clamping methods, causing welded plates to deform due to uneven welding tension.

The preheating of parts to be welded and slow cooling of the welded structure will lead to reduction in —-? (DMRC JE 2013)

• Residual stress and incomplete penetration
• Cracking and incomplete fusion
• Cracking and residual stress
• Cracking and underfill

Explanation:

• Preheating and slow cooling reduce residual stress and incomplete penetration.

Under filling in a weld joint is due to —-? (DMRC JE 20.04.2018)

• low temperature of welding
• melting away of base metal
• incomplete fusion
• incomplete filling of weld joints

Explanation:

• Under filling is due to incomplete filling of weld joints.

High alloy steel components are preheated before welding for reducing —-? (Konkan Railway STA 2017)

• Heat affected zone
• Total energy consumption
• Total time of welding
• Welding stresses

Explanation:

• High alloy steel components are preheated to reduce welding stresses. Hard and brittle materials are preheated to reduce residual stress and prevent cold cracks.

Cold-cracking in steel weldments depends on —-? (Konkan Railway TA 2017)

• 1, 2 and 3 only
• 1, 2 and 4 only
• 2, 3 and 4 only
• 1, 2, 3 and 4

Explanation:

• Cold-cracking depends on carbon equivalent, heat input, effective thickness, and hydrogen content in the weld pool.

A measure of the accuracy of a radiograph as an NDT tool is given by its —-? (RRB Kolkata Diesel JE 25.10.2009)

• Intensity
• Density
• Sensitivity
• Transverse waves

Explanation:

• The accuracy of radiography as an NDT tool is measured by sensitivity. Radiographic examination can detect cracks, internal porosity, holes, and inclusion of slag or oxides.

A surface breaking crack will be detected during a magnetic particle inspection if it is —-? (RRB Chandigarh SSE 25.10.2009)

• At right angles to the lines of flux
• Parallel to the line of flux
• At 25° to the line of flux
• All of the above

Explanation:

• A surface breaking crack is detected if it is at right angles to the lines of flux. Magnetic particle testing can reliably detect near-surface defects.

The advantage of ultrasonic non-destructive testing for the examination of weldments is —-? (RRB Mumbai C&G JE 25.10.2009)

• It can be used to locate flaws
• It can be used to size flaws
• It has a light sensitivity to planar flow
• All the above

Explanation:

• Ultrasonic testing uses sound waves from 20kHz to 20000kHz that pass through solids and return through defects, allowing detection of size, location, and position of defects.

Penetration inspection and magnetic particle inspection are mainly used —-? (RRB Gorakhpur RDSO SSE 25.10.2009)

• To aid visual inspection
• Because the application says so
• To confirm visual uncertainties
• All of these

Explanation:

• Penetration inspection and magnetic particle inspection are used as auxiliary to visual inspection and to confirm visual uncertainties.

In which type of test the capillary action principle is used? (RRB Makla SSE 25.10.2009)

• Probe test
• Bend liquid test
• Dye penetrant test
• None of the above

Explanation:

• Dye penetrant test uses capillary action where dye penetrates into surface cracks. It is used for both ferrous and non-ferrous weld joints.

Non-destructive testing is used to determine —-? (RRB Allahabad JE 25.10.2009)

• Location of defects
• Chemical composition
• Corrosion of metal
• All of these

Explanation:

• NDT methods can detect location of defects, chemical composition, and corrosion of metal without destroying the sample.

Which among the following is not a type of Non-destructive testing? (RRB Mumbai C&G SSE 25.10.2009)

• Compression test
• Visual testing
• Ultrasonic testing
• Eddy current testing

Explanation:

• Compression test is a destructive test used to find the compressive strength of welds.

Identify the type of destructive testing —-? (RRB Allahabad SSE 09.09.2012)

• Radiographic test
• Dye penetrant test
• Creep test
• All of the above

Explanation:

• Creep test is a destructive test. Radiographic, dye penetrant, and ultrasonic tests are non-destructive tests.

Which among the following is the last step in magnetic particle test method? (RRB Patna JE 25.10.2009)

• Observation and inspection
• Circular magnetization
• Demagnetization
• Magnetization

Explanation:

• Demagnetization is the last step in magnetic particle testing. The workpiece is magnetized, magnetic particles are spread, defects are verified, and then the workpiece is demagnetized.

Which of the following statements is/are true for ultrasonic test? (RRB Bhopal TM SSE 25.10.2009)

• Equipment used for ultrasonic testing is portable
• Complicated shapes can be easily scanned
• Waves generated are health hazardous
• All the above statements are true

Explanation:

• Ultrasonic testing equipment is lightweight and portable. Limitations include inability to detect complex shapes and limited penetration (6-10mm of steel).

During radiography test, which region absorbs less radiation and transmit more? (RRB Allahabad SSE 09.09.2012)

• Low and high density regions absorb and transmit same amount of radiation
• High density region
• Low density region
• None of the above

Explanation:

• Low density regions absorb less radiation and transmit more in radiography testing. X-rays pass through less dense media containing defects and reflect clearly on photographic film.

Which test is used to determine dimensions of any object? (RRB Bangalore SSE 09.09.2012)

• Ultrasonic test
• Torsion test
• Eddy current test
• All of these test can be used to determine dimensions of any object

Explanation:

• Eddy current test is used to determine dimensions and detect cracks and conductivity.

Which test can be performed without skilled labour? (RRB Gorakhpur Design SSE 09.09.2012) RRB Bangalore Material Engg. 21.11.2004

• Dye penetrant testing
• Visual testing
• Ultrasonic testing
• Magnetic particle test

Explanation:

• Visual testing can be performed without skilled labour.