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The correct option is (a) True

To explain I would say: FINE blanking is normally a single STEP finishing operation in which shearing is done with very SMALL clearances nearly about one PERCENT. Close tolerances are provided in order to achieve dimensional accuracy in the operation. In this PROCESS, smooth edges are produced by the application of clamping force on the blank which also avoids the distortion of sheet during operation.

Correct answer is (b) Inverse relation

Easy EXPLANATION: When the metal is entering, the width of the metal is inversely proportional to the LENGTH of the WORKPIECE, that is, with an increase in the width of the metal, there would be a decrease in the length of the workpiece and vice VERSA.

Right option is (a) Drop forging

Explanation: For the making of PRODUCTS like car AXLES, crankshafts, leaf springs and JET turbines, the METHOD of drop forging is USED.

Right option is (b) False

The explanation is: In DROP forging, the anvil is a LOT heavier than the hammer. To ABSORB the BLOW caused by the hammer, the anvil is made 20 times heavier than the hammer.

Correct ANSWER is (d) Quevering

Explanation: AMONG the following internal structure DEFECTS, quevering is not any kind of a DEFECT which can be regarded as an internal structure defect.

The CORRECT choice is (b) False

The explanation: It has been observed that PRESS forging is a PROCESS which WORKS more smoothly and is lot more accurate than drop forging.

The correct answer is (a) Zipper cracks

For explanation: Wavy EDGES and zipper cracks can OCCUR as defects in the material, if the rolls are bended, but not, FOLDS or laminations or alligatoring. Their causes of OCCURRENCE are DIFFERENT.

The correct option is (a) True

The explanation: In flash-less forging, the MATERIAL is fully RESTRICTED within the DIE, so no any flash is PRODUCED during the process, which completely optimizes the material used. But in impression die forging, flash can be produced which is considered as scrap material that is REMOVED from the formed part. So, the flash-less forging is better than the impression die forging for the minimum metal loss.

Right OPTION is (b) False

The explanation is: In hot rolling PROCESS, the VELOCITY of material at entry is LOWER than the velocity at EXIT.

Correct choice is (B) 4

The best I can explain: In FOUR high rolling mill, there are four rolls employed for roliing. The direction of two rollers is the same and the REMAINING two rollers roll in OPPOSITE DIRECTIONS.

Right choice is (b) False

Best EXPLANATION: In metal forming processes, the coefficient of FRICTION is very HIGH. DUE to this, it leads to a condition which is called as STICKING friction. In this case, the surface shear stress increases the shear yield strength of the metal and the surfaces adhere to each other. In the forming operation, the metal beneath the surface experiences shear deformation.

Correct answer is (a) True

The explanation is: A solid ram is used in DIRECT EXTRUSION or forward extrusion, whereas a HOLLOW ram is used in INDIRECT extrusion.

Correct ANSWER is (C) 0.03mm

To EXPLAIN I would say: It may be COUNTED among one of the limitations of DRAWING process, that very thin wires can only be drawn from it. In wire drawing process, wires can be drawn up to the size of 0.03mm.

Correct CHOICE is (C) Helmets

Best explanation: Among the following, helmets are not manufactured USING extrusion, WHEREAS all other products can be manufactured using extrusion.

Correct CHOICE is (d) Iron

The best explanation: EXTRUSION process is not suitable for any of the iron alloys, neither is it suitable for iron metal. For EXTRUDING stainless steel or other non-ferrous alloys or steel alloys, extrusion process can be USED.

Correct answer is (c) THREAD DIAMETER

Best explanation: In a RECIPROCATING flat DIE machine, the reciprocating die stroke depends upon the thread diameter, and there are 2 dies used in this APPARATUS, out of which, one is stationery.

Correct option is (b) Helmets

To explain: Rolling is very useful for MAKING articles like bars, PLATES and rails, but it cannot be used for making helmets. For making helmets, DIFFERENT METHODS of casting are used.

The correct OPTION is (C) Two high REVERSING mill

Explanation: In two high rolling mill, if the direction of the roller is REVERSED, then that SYSTEM is called as, two high reversing mill.

Correct ANSWER is (b) False

The best I can explain: Forming is basically a term that covers many manufacturing processes. In the metal forming process, the shape of the material or metal is CHANGED by performing an operation like hammering, squeezing, bending, pulling etc. without CHANGING its PHASE. The raw materials used in the forming process remained in a single solid phase.

The correct CHOICE is (a) True

Explanation: In the blanking operation, the MAIN function of the punch is to strike the metal SHEET, which is attached to the hub of the power PRESS machine. The striking power is mainly dependent on the capacity of machine used. The punch is attached through the machine by means of tapering at its TOP locked by a nut.

The correct choice is (b) Indirect extrusion

The best I can EXPLAIN: Direct extrusion is also called as BACKWARD extrusion. In this method, the METAL is EXTRUDED back into the PLUNGER.

Correct option is (a) BOARD hammer

The explanation is: Among the FOLLOWING type of drop hammers, that is, board hammer, air-lift hammer, power drop hammer and nail hammer, board hammer is ALSO called a gravity hammer.

Right choice is (c) Cogging

To elaborate: AMONG the FOLLOWING process, cogging is the OPERATION in which the surface is contoured a little. This process is also called as INCREMENTAL FORGING.

Right ANSWER is (d) Exiting velocity

The best I can explain: Exiting velocity, among the given FOUR VELOCITIES, that is slip velocity, SURFACE velocity, entering velocity and exiting velocity, the exiting velocity is considered to be having most MAGNITUDE.

Correct choice is (a) CLOCKWISE-anticlockwise

Explanation: In two high ROLLING mill, the DIRECTION of both the rollers is opposite to ONE another. Hence, one clockwise while other anti-clockwise.

Correct ANSWER is (c) SEPARATION rolling MILL

Explanation: Among two-high rolling mill, cluster rolling mill, separation rolling mill and TANDEM rolling mill. Separation rolling mill is not a type of rolling MILLS.

The CORRECT answer is (B) False

The best explanation: FORMING DIES are used for changing the shape of the blank without removing any material. For example, drawing dies and bending dies are forming dies. For blanking and piercing operations, cutting dies are used to CUT the metal from the metal sheet. They basically use cutting and shearing action for cutting the material.

Right choice is (b) False

For EXPLANATION I would say: In the blanking or punching operation, the punch diameter should be smaller than the die hole. The clearance between the die and the punch BASICALLY DEPENDS on the type of process used. For example, for blanking operation, the clearance is PROVIDED on the punch for OBTAINING the blank from metal sheet.

Correct CHOICE is (B) False

For explanation: Indirect extrusion or backward extrusion does not require a large AMOUNT of FORCE for operation, as the billet is stationery.

Right answer is (a) HOT FORGING

To elaborate: Among hot forging, cold forging, impact forging and GRADUAL PRESSURE forging, hot forging is done above the recrystallization temperature, but below the MELTING point.

The correct answer is (a) True

Easiest explanation: In general, the temperature rise of any material is determined by using the stress-strain plot. The temperature rise ALSO depends on the rate of deformation of the material. For slow deformation, the temperature rise of the metal is SMALL as the heat induced GETS dissipated through the surrounding air during the PROCESS.

Correct answer is (b) False

The EXPLANATION: Wire drawing process is quite different from deep drawing process. In wire drawing, metallic bar is pulled to FORM wires, while in deep drawing process; a flat metal sheet is converted into a concave shape part. This operation is basically performed by stretching the metal for which a BLANK-holder is used to clamp the blank on the die, and then a punch is used which pushes the metal sheet.

The correct ANSWER is (B) False

To elaborate: In hot working processes, the temperature at which the WORK takes place is not uniform. There is CHANGE of temperature that takes place in between the process when it is going on.

The correct OPTION is (b) Decreases

To elaborate: When the starting THICKNESS of the workpiece gets INCREASED, the REDUCTION of CORRESPONDINGLY gets decreased.

The correct choice is (B) 1200°C

Explanation: The material ingot is KNOWN for sustaining HIGH temperature and heat conditions. Before the PROCESS begins, the ingot is FIRED using gas and brought up to a temperature of 1200°C.

Correct answer is (c) INDIRECT compressive stress

The explanation is: WIRE drawing is a forming process in which a round metallic bar is pulled by a machine by generating indirect compressive stresses in the bar. This causes thinning of bar and results in the FORMATION of thin wires that further used as a cable or for ELECTRICITY PURPOSES. Wire drawing is most suitable for ductile materials.

The correct answer is (b) Injection moulding

Easy explanation: Extrusion, forging and drawing PROCESS are the main general types of metal forming process, while the injection moulding is other process which is basically a part of CASTING process which INCLUDES the formation of parts by injecting the MELT into a cavity by the help of a plunger. This method is not the part of metal forming because the phase change of metal occurs during the process.

The CORRECT answer is (b) False

For explanation: In the METAL forming process, drop hammers are MAINLY of two types which are gravity drop hammer and power drop hammer. Gravity drop hammers are the tools which achieve their ENERGY by the falling weight of a heavy ram. The force mainly depends on the height of the drop and the weight of the ram. And power drop hammers are in which a ram is ACCELERATED by the steam or pressurized air.

Correct CHOICE is (d) Extrusion

Easy EXPLANATION: Extrusion process is a type of metal FORMING process, in which the material is forced or squeezed out through a hole called die. This process is very similar to squeezing out the toothpaste from the tube. This process is MAINLY used for metals that are ductile in nature like copper, steel, ALUMINUM and magnesium; this process is also used for polymers.

The CORRECT ANSWER is (b) False

Explanation: Blanking is a kind of shearing operation which is generally carried out along a closed contour. In this operation, the required part is the material inside the sheared contour which is called as blank. For EXAMPLE, circular BLANKS are taken out from the metal sheet for subsequent DEEP drawing of cups.