Sheet Metal Forming Processes · Metal Forming · GATE PI

The ratio of press force required to punch a square hole of $$30$$ $$mm$$ side in a $$1$$ $$mm$$ thick aluminium sheet to that needed to punch a square hole of $$60$$ $$mm$$ side in a $$2$$ $$mm$$ thick aluminium sheet is________.

Circular blanks of $$10mm$$ diameter are punched from an aluminium sheet of $$2$$ $$mm$$ thickness. The shear strength of aluminium is $$80$$ $$MPa.$$ The minimum punching force required in $$kN$$ is

Match the following metal forming processes with their associated stresses in the Work-piece

Which one is not a method of reducing cutting forces to prevent the overloading of press

A cup of $$10$$ $$cm$$ height and $$5$$ $$cm$$ diameter is to be made from a sheet metal of $$2mm$$ thickness. The number of deductions necessary will be

For $$50\% $$ penetration of work material, a punch with single shear equal to thickness will

In a bending operation, If the modulus of elasticity $$E$$ is increased keeping all other parameters unchanged, the spring back will

In blanking operation, the best way to improve the smoothness and squarness of the edges is to

In producing a punched hole of $$20mm$$ diameter, the dimension of the punch is ........ given the radial die clearance of $$0.1mm.$$

The function of draw bead in the deep drawing operation is to

Wall thickness of drawn cup is controlled by

In .................. A ................. operation the diameter of the desired hole will be smaller than the diameter of the .................... B ......................

A. blanking / piercing
B. punch / die

A cup of $$10$$ $$cm$$ height and $$5$$ $$cm$$ diameter is to be made from a sheet metal of $$2mm$$ thickness. The number of deductions necessary will be

In progressive die (for sheet metal), spring loaded stripper plate is used to clamps the stock until:

Calculate the punch size in $$mm,$$ for a circular blanking operation for which details are given below.

Size of the blank $$25$$ $$mm$$
Thickness of the sheet $$2$$ $$mm$$
Radial clearance between punch and die $$0.06$$ $$mm,$$ Die allowance $$0.05$$ $$mm$$

A disc of $$200$$ $$mm$$ diameter is blanked from a strip of an aluminium alloy of thickness $$3.2$$ $$mm.$$ The material shear strength to fracture is $$150$$ $$MPa.$$ The blanking force (in $$kN$$) is

Match the following

A blank of $$50$$ $$mm$$ diameter is to be sheared from a sheet of $$2.5$$ $$mm$$ thickness. The required radial clearance between the die and the punch is $$6\% $$ of sheet thickness. The punch and die diameter $$(mm)$$ for this blanking operation respectively are

Circular blanks of $$35$$ $$mm$$ diameter are punched from a steel sheet of $$2$$ $$mm$$ thickness. If the clearance per side between the punch and die is to be kept as $$40$$ microns, the sizes of punch and die should respectively be.

A cup is to be drawn to a diameter of $$70mm$$ with $$35mm$$ depth from a $$0.5mm$$ thick sheet metal. The cup is drawn in one operation. Assume $${\sigma _u} = 430\,\,MPa.$$

The required blank diameter is

A cup is to be drawn to a diameter of $$70mm$$ with $$35mm$$ depth from a $$0.5mm$$ thick sheet metal. The cup is drawn in one operation. Assume $${\sigma _u} = 430\,\,MPa.$$

The maximum drawing force is

It is required to punch a hole of diameter $$10mm$$ on a sheet of thickness $$3mm.$$ The shear strength of the work material is $$420Mpa.$$ The required punch force is

A work piece of $$1000$$ $$mm$$ length and $$300$$ $$mm$$ width is machined by planning operation with a feed of $$0.3$$ $$mm/stroke.$$ The machine tool executes $$10$$ double strokes per minute. The planning time for a single pass is

A gear with $$84$$ teeth is to be machined using a milling process with indexing. The index plate has the following four hole circles: $$36,38, 42., 48.$$ The change gear ratio required is

Match the items in Group - $${\rm I}$$ and $${\rm I}$$ $${\rm I}$$

In a surface broaching process, a broach having $$5mm$$ pitch and cut per teeth $$0.05mm$$ is used for reducing the thickness by $$6mm.$$ If the length of the work piece is $$50mm$$ and the cutting speed is $$0.05m/s,$$ the time required / pass in seconds is

It is required to punch a hole of diameter $$10mm$$ on a sheet of thickness $$3mm.$$ The shear strength of the work material is $$420MPa.$$ The required punch force is

A $$\phi \,\,25$$ $$mm$$ hole is pierced in a $$t=2.5mm$$ thick steel sheet having shear strength $$\tau = 350\,\,MPa.$$ If the diametral clearance is given by the expression $$C=0.0064$$ $$t$$ $$\sqrt \tau ,$$ the die diameter (in $$mm$$), punch diameter (in $$mm$$) and punch force in $$(kN)$$ respectively are

A cylindrical cup of $$48.5$$ $$mm$$ diameter and $$52$$ $$mm$$ height has a corner radius of $$1.5$$ $$mm$$ Cold rolled steel sheet of thickness $$1.5$$ $$mm$$ is used to produce the cup. Assume trim allowance as $$2$$ $$mm$$ per $$25$$ $$mm$$ of cup diameter. What is the blank size in $$mm$$ ?

Determine the load required to punch a $$20$$ $$mm$$ diameter hole in $$2$$ $$mm$$ thick sheet. The properties of the material of the sheet are:
Tensile strength $$-580$$ $$MPa;$$
Yield strength in tension $$-410$$ $$MPa$$
Shear strength $$-350$$ $$MPa;$$
Yield strength in shear $$-250$$ $$MPa$$

The load in $$kN$$ is:

A hole of $$40$$ $$mm$$ diameter is pierced in a steel sheet of $$4$$ $$mm$$ thickness without shear on the tool. Shear strength of steel is $$400$$ $$N/m{m^2},$$ and penetration is $$25\% .$$ What is the expected percentage load reduction if a shear of $$1$$ $$mm$$ is provided on the punch?

In deep drawing of sheet metal, spring loaded stripper clamps the work until:

A hydraulic press is used to produce circular blanks of $$10$$ $$mm$$ diameter from a sheet of $$2$$ $$mm$$ thickness. If the shear strength of the sheet material is $$400$$ $$N/m{m^2},$$ the force required for producing a circular blank is

Consider the following statements related piercing and blanking
$$1.$$ Shear on the punch reduces the maximum cutting force
$$2.$$ Shear increases the capacity of the press needed
$$3.$$ Shear increases the life of the punch
$$4.$$ Total energy needed to make the cut remains unaltered due to provision of shear

Which of the above statements are correct

In sheet metal working, the spring back increase when
$$P:$$ Ratio of bend radius to sheet thickness is small
$$Q:$$ Young's modulus of the sheet is low
$$R:$$ Yield strength of the sheet is high
$$S:$$ Tension is applied during bending

In metal forming operation, the true strain in the $$X$$-direction is $$0.3$$ and in the $$Y$$-direction is $$-0.1.$$ The true strain in the $$Z$$-direction is

A hemispherical cup of radius $$'R'$$ is formed in a press working operation. The radius of blank would be

Calculate the smallest punch diameter that can be designed for piercing sheet metal strip with the following data. Crushing strength of the punch material is $$1500$$ $$MPa.$$ Thickness of the sheet is $$2$$ $$mm,$$ factor of safety is $$3,$$ and shear strength of the sheet material $$500$$ $$MPa$$ is