According to I.B.R., the factor of safety of riveted joint should not be less than
1
2
3
4
Correct Answer :
D. 4
Related Questions
For high speed engines, the cam follower should move with
Uniform velocity
Simple harmonic motion
Uniform acceleration and retardation
Cycloidal motion
In a full journal bearing, the angle of contact of the bearing with the journal is
120°
180°
270°
360°
In a partial journal bearing, the angle of contact of the bearing with the journal is
120°
180°
270°
360°
A universal coupling is used to connect two shafts
Which are not in exact alignment
Which are perfectly aligned
Whose axes intersect at a small angle
Have lateral misalignment
The face of the tooth is the
Surface of the top of the tooth
Surface of the tooth above the pitch surface
Surface of the tooth below the pitch surface
Width of the tooth measured along the pitch circle
The circumferential and longitudinal strains in a cylindrical boiler under internal steam pressure are εc and εl respectively. The change in volume of the boiler cylinder per unit volume will be
εc + 2εl
2εc + εl
εc + εl²
εc² + εl
The distribution of the forces along the length of key fitted in a shaft
Varies linearly
Is uniform throughout
Varies exponentially, being more near the torque-input end
Varies exponentially, being less near the torque-input end
In a hydrodynamic lubricated bearing
There is a thick film of lubricant between the journal and the bearing
There is a thin film of lubricant between the journal and the bearing
The lubricant is forced between the journal and the bearing, by external pressure
There is no lubricant between the journal and the bearing
In case of thick cylinders, the tangential stress across the thickness of cylinder is
Maximum at the outer surface and minimum at the inner surface
Maximum at the inner surface and minimum at the outer surface
Maximum at the inner surface and zero at the outer surface
Maximum at the outer surface and zero at the inner surface
The shock absorbing capacity of a bolt can be increased by
Tightening it properly
Increasing shank diameter
Grinding the shank
Making shank diameter equal to core diameter of thread.
In the case of an elastic bar fixed at upper end and loaded by a falling weight at lower end, the shock load produced can be decreased by
Decreasing the cross-section area of bar
Increasing the cross-section area of bar
Remain unaffected with cross-section area
Would depend upon other factors
Which of the following statement is wrong?
A key is used as a temporary fastening
A key is subjected to tensile stresses
A key is always inserted parallel to the axis of the shaft
A key prevents relative motion between the shaft and boss of the pulley
Two shafts A and B under pure torsion are of identical length and identical weight and are made of the same material. The shaft A is solid and the shaft B is hollow. We can say that
Shaft B is better than shaft A
Shaft A is better than shaft B
Both the shafts are equally good
None of these
The valve rod in a steam engine is connected to an eccentric rod by
Cotter joint
Bolted joint
Knuckle joint
Universal coupling
The square threads are usually found on
Spindles of bench vices
Railway carriage couplings
Feed mechanism of machine tools
Screw cutting lathes
The stress in the threaded part of the bolt will be __________ as compared to the shank.
Same
Higher
Lower
None of these
Oldham coupling is used to connect two shafts
Which are perfectly aligned
Which are not in exact alignment
Which have lateral misalignment
Whose axes intersect at a small angle
An imaginary circle which by pure rolling action gives the same motion as the actual gear, is called
Addendum circle
Dedendum circle
Pitch circle
Clearance circle
A shaft is subjected to a maximum bending stress of 80 N/mm² and maximum shearing stress equal to 30 N/mm² at a particular section. If the yield point in tension of the material is 280 N/mm² and the maximum shear stress theory of failure is used, then the factor of safety obtained will be
2.5
2.8
3.0
3.5
Spring stiffness is
Ratio of coil diameter to wire diameter
Load required to produce unit deflection
Its capability of storing energy
Its ability to absorb shocks
The pipe joint mostly used for pipes carrying water at low pressures is
Socket joint
Nipple joint
Union joint
Spigot and socket joint
The included angle for the V-belt is usually
10°-20°
30°-40°
40°-60°
60°-80°
A taper key which fits half in the key way of the hub and half in the key way of shaft, is known as
Angular bevel gears
Mitre gears
Crown Bevel gears
Internal bevel gears
Which one of the following loading is considered for the design of axles?
Bending moment only
Twisting moment only
Combined bending moment and twisting moments
Combined action of bending moment, twisting moment and axial thrust
Two closely coiled helical springs with stiffness k₁ and k₂ respectively are connected in series. The stiffness of an equivalent spring is given by
(k₁ k₂)/ (k₁ + k₂)
(k₁ - k₂)/ (k₁ + k₂)
(k₁ + k₂)/ (k₁ k₂)
(k₁ - k₂)/ (k₁ k₂)
A screw is said to be over hauling screw, if its efficiency is
More than 50 %
Less than 50 %
Equal to 50 %
None of these
Machine screws are
Similar to small size tap bolts except that a greater variety of shapes of heads are available
Slotted for a screw driver and generally used with a nut
Used to prevent relative motion between two parts
Similar to stud
The designation M 33 × 2 of a bolt means
Metric threads of 33 numbers in 2 cm
Metric threads with cross-section of 33 mm
Metric threads of 33 mm outside diameter and 2 mm pitch
Bolt of 33 mm nominal diameter having 2 threads per cm
A fast and loose pulley drive is used when
Shafts are arranged parallel and rotate in the opposite directions
Shafts are arranged parallel and rotate in the same directions
Shafts are arranged at right angles and rotate in one definite direction
Driven shaft is to be started or stopped whenever desired without interfering with the driving shaft
The permissible stress in the fillet weld is 100 N/mm². The fillet weld has equal leg lengths of 15 mm each. The allowable shearing load on the weldment per cm length of the weld is
7.5 kN
10.6 kN
15 kN
22.5 kN