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
.
View Answer
Answer: c
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
View Answer
Answer: d
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
View Answer
Answer: b
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
View Answer
Answer: d
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%
View Answer
Answer: c
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
View Answer
Answer: c
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
View Answer
Answer: c
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
View Answer
Answer: a
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
View Answer
Answer: b
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
View Answer
Answer: c
Explanation: p+2m=w or p+2×1.5×10=80.