211. In a marine flange coupling, the pitch circle diameter of bolts is taken as
1.2 d
1.6 d
2 d
2.5 d
✅ The correct answer is option B.
Machine Design MCQs
212. The design calculations for members subject to fluctuating loads with the same factor of safety, yield the most conservative estimates when using
Gerber relation
Soderberg relation
Good man relation
none of these
✅ The correct answer is option C.
213. A screw is said to be over hauling screw, if the
friction angle is less than helix angle
friction angle is more than helix angle
friction angle is equal to helix angle
efficiency of screw is
✅ The correct answer is option A.
214. When the material of key and shaft is same, and the width of key is one-fourth of the diameter of shaft (d), then length of key will be
0.8 d
1.2 d
1.57 d
1.8 d
✅ The correct answer is option C.
215. Which of the following cotter joint will be used to connect strap end of a connecting rod ?
Spigot and socket cotter joint
Sleeve and cotter joint
Gib and cotter joint
any one of these
✅ The correct answer is option C.
216. The metal suitable for bearings subjected to light loads is
silicon bronze
white metal
monel metal
phosphor bronze
✅ The correct answer is option D.
217. When the screw in a mechanical screw jack rotates, the load kept on the top of it moves
axially upwards
axially downwards
axially upwards or downwards
none of these
✅ The correct answer is option C.
218. For longitudinal joint in boilers, the type of joint used is
butt joint with single cover plate
butt joint with double cover plate
lap joint with one ring overlapping the other
any one of the above
✅ The correct answer is option B.
219. Wahl’s stress factor __________ very rapidly as the spring index decreases.
increases
decreases
✅ The correct answer is option A.
220. In the levers of third type, the mechanical advantage is __________ one.
less than
equal to
more than
✅ The correct answer is option A.