Questions without a selected answer in Machine Design

A rectangular plate is perfectly welded to a gusset plate with parallel fillet weld joints as shown in the figure below. The length of the weld is $l$ and the fillet weld...

​​​​A shaft carries a helical spur gear. Which one of the following bearings can NOT be used to support it?Angular contact bearingDouble-row ball bearingStraight roller b...

A pair of spur gears is required to maintain a velocity ratio of $1: 2$. The module of the gears is $10 \: mm$ and the addendum is $10 \: mm$. If the operating pressure a...

​​​For a ball bearing, the fatigue life in millions of revolutions is given by $L=\left(\frac{C}{P}\right)^{n}$, where $\text{P}$ is the constant applied load and $\text{...

​​​​Which one of the following failure theories is the most conservative design approach against fatigue failure?Soderberg lineModified Goodman lineGerber lineYield line

Two meshing spur gears $1$ and $2$ with diametral pitch of $8$ teeth per mm and an angular velocity ratio $\left|\omega_{2}\right| /\left|\omega_{1}\right|=1 / 4$, have t...

Which one of the following $\text{CANNOT}$ impart linear motion in a $\text{CNC}$ machine?Linear motorBall screwLead screwChain and sprocket

A square threaded screw is used to lift a load $W$ by applying a force $F$. Efficiency of square threaded screw is expressed asThe ratio of work done by $W$ per revolutio...

Shear stress distribution on the cross-section of the coil wire in a helical compression spring is shown in the figure. This shear stress distribution representsdirect sh...

A short shoe drum (radius $\text{260 mm}$) brake is shown in the figure. A force of $\text{1 kN}$ is applied to the lever. The coefficient of friction is $0.4$.The magnit...

A machine part in the form of cantilever beam is subjected to fluctuating load as shown in the figure The load varies from $\text{800 N}$ to $\text{1600 N}$. The modified...

Two plates, each of $6$ mm thickness, are to be butt-welded. Consider the following processes and select the correct sequence in increasing order of size of the heat affe...

A machine member is subjected to fluctuating stress $\sigma = \sigma_0 \cos (8 \pi t)$. The endurance limit of the material is $350$ MPa. If the factor of safety used in ...

A bolt head has to be made at the end of a rod of diameter $d=12$ mm by localized forging (upsetting) operation. The length of the unsupported portion of the rod is $40$ ...

A steel spur pinion has a module $(m)$ of $1.25$ mm, $20$ teeth and $20^\circ$ pressure angle. The pinion rotates at $1200$ rpm and transmits power to a $60$ teeth gear. ...

In a disc-type axial clutch, the frictional contact takes place within an annular region with outer and inner diameters $250\:mm$ and $50\:mm$, respectively. An axial for...

A spur gear has pitch circle diameter $D$ and number of teeth $T$. The circular pitch of the gear is $\dfrac{\pi D}{T} \\$$\dfrac{T}{D} \\$$\dfrac{D}{T} \\$$\dfrac{2 \pi ...

A spur gear with $20^{\circ}$ full depth teeth is transmitting $20 \: kW$ at $200 \: rad/s$. The pitch circle diameter of the gear is $100 \: mm$. The magnitude of the fo...

A bar is subjected to a combination of a steady load of $60 \: kN$ and a load fluctuating between $-10 \: kN$ and $90 \: kN$. The corrected endurance limit of the bar is ...

Pre-tensioning of a bolted joint is used tostrain harden the bolt headdecrease stiffness of the bolted jointincrease stiffness of the bolted jointprevent yielding of the ...

A frictionless gear train is shown in the figure. The leftmost $12$-teeth gear is given a torque of $100 \: N-m$. The output torque from the $60$-teeth gear on the right ...

The schematic of an external drum rotating clockwise engaging with a short shoe is shown in the figure. The shoe is mounted at point Y on a rigid lever XYZ hinged at poin...

A self-aligning ball bearing has a basic dynamic load rating $(C_{10}$, for $10^6$ revolutions) of $35$ kN. If the equivalent radial load on the bearing is $45$ kN, the e...

For an Oldham coupling used between two shafts, which among the following statements are correct?Torsional load is transferred along shaft axisA velocity ratio of $1:2$ b...

Cylindrical pins of diameter $15^{\pm0.020}$ mm are being produced on a machine. Statistical quality control tests show a mean of $14.995$ mm and standard deviation of $0...

During the development of a product, an entirely new process plan is made based on design logic, examination of geometry and tolerance information. This type of process p...

In a simple concentric shaft-bearing arrangement, the lubricant flows in the $2$ $mm$ gap between the shaft and the bearing. The flow may be assumed to be a plane Couette...