# Machine Design Questions and Answers – Butt Joints & Fillet Joins

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This set of Machine Design Multiple Choice Questions & Answers (MCQs) focuses on “Butt Joint & Fillet Joints”.

1. If force act in a direction parallel to the direction of weld, then fillet weld is called as?
a) Transverse
b) Longitudinal
c) Parallel
d) Longitudinal or Parallel

Explanation: Parallel fillet weld consist of force acting in a direction of weld.

2. Convex weld is generally preferred over normal weld.
a) True
b) False

Explanation: There is more stress concentration in convex weld and hence is less preferred.

3. Parallel fillet weld and transverse fillet weld both have the plane in which maximum shear stress occurs at 45’ to the leg dimension.
a) True
b) False

Explanation: Transverse fillet weld has that plane inclined at 67.5 .

4. The length of each of the two equal sides of a parallel fillet weld is called
a) Leg
b) Throat
c) Arm
d) None of the listed

Explanation: Leg is the length of each of the two equal sides of a parallel fillet weld.

5. Relation between throat and leg for a parallel fillet weld is
a) t =h Cos (45’)
b) h =t Cos (45’)
c) h= t
d) None of the listed

Explanation: Throat is the minimum cross section of the weld and that plane lies at 45’ for a parallel fillet weld.

6. If length of weld is l and leg h, then area of throat can be given by
a) 0.707 hl
b) 1.414hl
c) hl
d) None of the listed

Explanation: Area=t x l where t=h Cos (45’).

7. A steel plate is welded to another steel plate as shown in the below figure. This is an example of transverse fillet weld. a) True
b) False

Explanation: The force acts parallel to the direction of weld and hence is an example of double parallel fillet weld.

8. Referring to the below figure, determine the required length of the weld joining two steel plates which are 10mm wide and 10mm thick. The permissible shear stress in the weld is 80N/mm². a) 18mm
b) 15mm
c) 16mm
d) 14mm

Explanation: P=2 x 0.707 hlτ or 20000=1.414x10xlx80 or l=17.68mm.

9. The two plates are welded as shown below figure. It is an example of a) Parallel fillet weld
b) Transverse fillet weld
c) Parallel as well as transverse fillet weld
d) None of the mentioned

Explanation: In two welds force acts parallel as well as perpendicular to the direction of weld.

10. With reference to the following figure, a plate, 75mm wide and 10mm thick, is joined with another plate as shown. The permissible tensile and shear stress in the welds are 50/mm² and 40N/mm². Determine the required length of each parallel fillet weld if length of transverse weld is 40mm. a) 11mm
b) 9mm
c) 8mm
d) 7mm

Explanation: 0.707hl₁σ+1.414hl₂τ=20000 or 0.707x10x50x40+1.414x10xl₂x40=20000.

11. Strength of parallel fillet weld is greater than strength of transverse fillet weld.
a) True
b) False 