# MCQs on Failure in Rivets

1 - Question

This set of Machine Design Multiple Choice Questions & Answers (MCQs) focuses on “Rivets Analysis”. Figure 1
Two plates are joined by double strap butt joints with rivets arrangement as shown in the figure. Width of the plate is 300mm and diameter of rivets 30mm. The thickness of the plates can be taken as 20mm.Allowable stress in tension, shear and compression are 80 N/mm²,60 N/mm² and 160N/mm².

Answer the following questions with respect to figure 1
Calculate the shear resistance of 1 rivet along A-A.

a) 21.2kN
b) 42.4kN
c) 84.8kN
d) None of the listed
.

Explanation: P=2x[τ x πd²/4]

2 - Question

Calculate the tensile strength of rivet along A-A.

a) 2592kN
b) 864kN
c) 216kN
d) 432kN

Explanation: Strength=(w-d)xtxσ.

3 - Question

Calculate the tensile strength of rivets along B-B.

a) 84.8kN
b) 468.8kN
c) 384kN
d) None of the listed

Explanation: To fail along B-B, rivet in outermost row must undergo shear failure. Strength = (w-2d)x σ x t + 1xP(shear) = (300-60)x80x20/1000 + 84.8.

4 - Question

Calculate the tensile strength of rivets along C-C.

a) 772kN
b) None of the listed
c) 336kN
d) 590.4kN

Explanation: To fail along C-C, rivets in outer rows must undergo shear failure. Strength= (w-3d)x σ x t + 3xP(shear) = (300-90)x80x20/1000 + 3×84.8.

5 - Question

Calculate efficiency of the joint.

a) 45%
b) 85%
c) 90%
d) 100%

Explanatio: Strength along A-A, B-B and C-C are 432kN, 468.8kN and 590.4kN and strength of solid plate=wσt=480kN. Lowes is along AA. Hence efficiency=432/480.

6 - Question

Calculate the crushing resistance of 1 rivet.

a) 1153kN
b) 108kN
c) 96kN
d) 576kN

Explanation: P=dtσ= 30x20x160=96kN.

7 - Question

Calculate the pitch of the rivets.

a) None of the listed
b) 210mm
c) 105mm
d) 52.5mm

Explanation: m+p+p+m=w where m=1.5d.

8 - Question

The type of arrangement shown is

a) Lozenge Joint
b) Lap Joint
c) Star Joint
d) Darwin’s Joint

Explanation: Lozenge joint is other name of diamond shape joint.

9 - Question

If circumferential stress is P, then longitudinal stress in the pressure vessel is?

a) 2P
b) P/2
c) P
d) None of the listed

Explanation: Circumferential stress=2x longitudinal stress.

10 - Question

If width of plate=80mm ad diameter of rivets 10mm, then pitch will be?

a) 65mm
b) 60mm
c) 50mm
d) 70mm