Bissoy.com
Doctors Medicines MCQs Q&A

A hole of diameter (d) is to be punched through a sheet metal of thickness (t). How much force is required to punch the hole if the ultimate shear stress of the sheet metal is (τ)?

A hole of diameter (d) is to be punched through a sheet metal of thickness (t). How much force is required to punch the hole if the ultimate shear stress of the sheet metal is (τ)? Correct Answer πdtτ

Concept:

In punching and blanking, the shearing action on the sheet takes place which will depend on the shear strength of the metal.

Punching force F = Lt τ

Where L is Length of the periphery, t = thickness, τ = Ultimate shear strength

For circular section L = πd

∴ F = πdtτ

Related Questions

When a hole of diameter ‘d’ is punched in a metal of thickness 't', then the force required to punch a hole is equal to (where $${\tau _{\text{u}}}$$ = Ultimate shear strength of the material of the plate)
The maximum diameter of the hole that can be punched from a plate of maximum shear stress $${\frac{1}{4}^{{\text{th}}}}$$ of its maximum crushing stress of punch, is equal to (where t = Thickness of the plate)
Tresca or maximum-shear stress criteria assumes that yielding occurs when the maximum shear stress reaches a value of the shear stress in the uniaxial tension test. Assume the principal stress being σ1, σ2, σ3 where σ1 is largest, and σ3 is the smallest principal stresses. Find the value of minimum shear stress to cause yielding, given that yield stress in tension is equal to σo?
A rock specimen of average thickness 0.8 cm failed at an applied load of 1000 kg during determination of shear strength by the punch test. The diameter of the punch is 2.8 cm, The shear strength of the rock specimen in kg/ cm2 is
Calculate the work done per minute by a punch tool making 20 working strokes per min when a 30 mm diametre hole is punched in 5 mm thick plate with ultimate shear strength og 450 Mpa in each stroke.
The ultimate shear force at a section of an RCC beam is 300 kN. The shear resisted by concrete is 77.5 kN. What is the shear for which shear reinforcement is required?
The maximum shear force required to cause the fracture on any metal surface is empirically defined as _____________ (Where σu – ultimate tensile strength of the metal, h-sheet thickness, L- total length of the sheared edge)
Check for ultimate shear strength such that shear force, Vu = 2834 kn, According to IRC: 18-2000, the ultimate shear resistance of the support section uncracked in flexure loss ratio is 0.8, p is 12000×103, area is 0.88 x 106mm2?
Which of the following factors are affecting critical shear stresses? 1. Purity of metals reduces the critical shear stress 2. Surface films greatly enhance the critical shear stress 3. Rise in temperature 4. Rate of deformation and the extent of initial deformation also help in raising the critical shear stress
In seive plate column, holes are drilled or punched in sizes ranging from 2.5 to 12 mm (5 mm being widely used). The hole pitch is normally __________ times the hole diameter to give the required hole area.