The connecting rod bolts are tightened up with initial tension greater than the external load so that
Joint may not open up
Bolts are weakest elements
The resultant load on the bolt would not be affected by the external cyclic load
Bolts will not loosen during service
Correct Answer :
C. The resultant load on the bolt would not be affected by the external cyclic load
Related Questions
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
In case of V-belt drive
The belt should touch the bottom of groove in the pulley
The belt should not touch the bottom of groove in the pulley
The belt should not touch the sides of groove in the pulley
None of the above
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
Split nut is a locking device in which
One smaller nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming
A slot is cut partly in middle of nut and then slot reduced by tightening screw
A hard fibre or nylon cotter is recessed in the nut and becomes threaded as the nut is screwed on the bolt causing a tight grip
Through slots are made at top and a cotter pin is passed through these and a hole in the bolt, and cotter pin splitted and bent in reverse direction at the other end
The pitch diameter is the __________ diameter of an external or internal screw thread.
Effective
Smallest
Largest
None of these
Endurance limit or fatigue limit is the maximum stress that a member can withstand for an infinite number of load applications without failure when subjected to
Dynamic loading
Static loading
Combined static and dynamic loading
Completely reversed loading
The contact ratio for gears is
Zero
Less than one
Greater than one
None of these
The standard length of the shaft is
6 m
5 m
7 m
All of these
The taper on key is given on
Bottom side only
Top side only
On both sides
Any side
In worm gears, the angle between the tangent to the pitch helix and an element of the cylinder, is known as
Helix angle
Pressure angle
Pitch lead angle
None of these
The ultimate strength of steel in tension in comparison to shear is in the ratio of
1 : 1
2 : 1
3 : 2
2 : 3
In unilateral system of tolerance, the tolerance is allowed on
Both sides of the actual size
One side of the actual size
One side of the nominal size
Both sides of the nominal size
The temperature at which the new grains are formed in the metal is known as
Lower critical temperature
Upper critical temperature
Recrystallisation temperature
None of these
The groove angle of pulleys for V-belt is
340 to 360
420 to 450
More than 400
300 to 320
Screws used for power transmission should have
Low efficiency
High efficiency
Very fine threads
Strong teeth
The objective of caulking in a riveted joint is to make the joint
Free from corrosion
Stronger in tension
Free from stress
Leak-proof
In designing a sleeve coupling, length of the sleeve is taken as (where d = Diameter of the shaft)
d + 17 mm
2d + 13 mm
2d + 20 mm
3.5d
Stress concentration in cyclic loading is more serious in
Ductile materials
Brittle materials
Equally serious in both cases
Depends on other factors
In replacing the V-belts, a complete set of new belts is used instead of replacing a single damaged belt because
Belts are available in sets
Only one belt cannot be fitted with other used belts
The new belt will carry more than its share and result in short life
New and old belts will cause vibrations
According to Unwin's formula, the relation between the diameter of rivet hole (d) and the thickness of plate (t) is given by (where d and t are in mm)
d = t
d = 1.6 t
d = 2t
d = 6t
In the assembly of pulley, key and shaft
Pulley is made the weakest
Key is made the weakest
Key is made the strongest
All the three are designed for equal strength
Stress concentration is caused due to
Variation in properties of material from point to point in a member
Pitting at points or areas at which loads on a member are applied
Abrupt change of section
All of the above
For a shaft diameter of 100 mm, the number of bolts in a flange coupling should be
4
6
8
10
In leaf springs, the longest leaf is known as
Master leaf
Lower leaf
Upper leaf
None of these
When an open coiled helical compression spring is subjected to an axial compressive load, the stress induced in the wire is
Tensile stress
Compressive stress
Shear stress
Bending stress
The most important dimension in the design of a nut is
Pitch diameter
Inside diameter
Outside diameter
Height
Which of the following statement is correct?
The stress concentration in static loading is more serious in ductile materials and less serious in brittle materials
The stress concentration in static loading is more serious in brittle materials and less serious in ductile materials
The toughness of a material increases when it is heated
The shear stress in a beam varies from zero at the neutral surface and maximum at the outer fibres
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
When compared to the rod of the same diameter and material, a wire rope
Is less flexible
Has a much smaller load carrying capacity
Does not provide much warning before failure
Provides much greater time for remedial action before failure
When a nut is tightened by placing a washer below it, the bolt will be subjected to following type of loads
Compression
Tension
Shear
Combined loads