The centre to centre distance between two consecutive rivets in a row, is called
Margin
Pitch
Back pitch
Diagonal pitch
Correct Answer :
B. Pitch
Related Questions
The period during which the cam follower remains at rest, when cam moves, is known as
Constant period
Fixed period
Dwell period
Idle period
In order to determine the stresses in a thin cylinder due to an internal pressure, it is assumed that
The effect of curvature of the cylinder wall is neglected
The tensile stresses are uniformly distributed over the section of the walls
The effect of the restraining action of the heads at the end of the pressure vessel is neglected
All of the above
When screw threads are to be used in a situation where power is being transmitted in one direction only, then the screw threads suitable for this will be
Knuckle threads
Square threads
Acme threads
Buttress threads
The pitch of threads on a Jock nut in comparison to pitch of nut is
Same
Coarser
Finer
Very fine
In block brakes, the ratio of shoe width to wheel diameter is taken between
0.1 and 0.25
0.25 and 0.50
0.50 and 0.75
0.75 and 1
A tap bolt
Has a head on one end and a nut fitted to the other
Has head at one end and other end fits into a tapped hole in the other part to be joined
Has both the ends threaded
Has pointed threads
A steel containing __________ 0.8% carbon is known as hypoeutectoid steel.
Equal to
Less than
Greater than
None of these
The fatigue stress concentration factor is defined as
The ratio of endurance limit with stress concentration to the endurance limit without stress concentration
The ratio of endurance limit without stress concentration to the endurance limit with stress concentration
The product of the endurance limits with and without stress concentration
All of the above
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
If shearing stress in nut is half the tensile stress in a bolt, then nut length should be equal to
Diameter of bolt
0.75 × diameter of bolt
1.25 × diameter of bolt
1.5 × diameter of bolt
According to I.B.R., the distance between the rows of rivets, for equal number of rivets in more than one row for lap joint or butt joint (chain riveting) shall not be less than
d
1.5 d
2d
2.5 d
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
The taper on key is given on
Bottom side only
Top side only
On both sides
Any side
Two rigid plates are clamped by means of bolt and nut with an initial force F. After tightening, a separating force P (P < F) is applied to the lower plate, which in turn acts on the nut. The tension in the both after this is
F + P
F P
P
F
Which process will increase the fatigue duration of parts?
Finishing and polishing
Shotpeening
De-carburisation
Electroplating
Crowning on pulley helps
In decreasing the slip of the belt
In increasing the slip of the belt
To keep the belt in centre on a pulley while it is in motion
To increase pulley life
A screw is said to be a self locking screw, if its efficiency is
Less than 50 %
More than 50 %
Equal to 50 %
None of these
Stress concentration is caused due to
Variations in load acting on a member
Variations in properties of materials in a member
Abrupt change of cross-section
All of these
The application of third type levers is found in
Handle of a hand pump
Hand wheel of a punching press
Lever of a loaded safety valve
A pair of tongs
In designing thick cylinders, the equation used is
Lame's equation
Birnie's equation
Clavarinos' equation
All of these
A spring is used to
Measure forces
Apply forces
Store energy
All of these
The ratio of the ultimate stress to the design stress is known as
Elastic limit
Strain
Factor of safety
Bulk modulus
Spring index is
Ratio of coil diameter to wire diameter
Load required to produce unit deflection
Its capability of storing energy
Indication of quality of spring
The temperature required for full annealing in hypereutectoid steel is
50°C above upper critical temperature
50°C below upper critical temperature
50°C above lower critical temperature
50°C below lower critical temperature
In a multiple V-belt drive, when a single belt is damaged, it is preferable to change the complete set in order to
Reduce vibration
Reduce slip
Ensure uniform loading
Ensure proper alignment
Surface endurance limit of gear material is dependent upon its
Elastic strength
Yield strength
Brinell hardness number
Toughness
Two helical springs of the same material and of equal circular crosssection, length and number of turns, but having radii 80 mm and 40 mm, kept concentrically (smaller radius spring within the larger radius spring), are compressed between two parallel planes with a load W. The inner spring will carry a load equal to
W/2
2W/3
W/9
8W/9
Three different weights fall from a certain height under vacuum. They will take
Same time to reach earth
Times proportional to weight to reach earth
Times inversely proportional to weight to reach earth
None of the above
A triple riveted butt joint with double straps of unequal width is to be designed for a boiler shell. The pitch of the rivets in the outer row is double the pitch in the inner row and zigzag riveting is proposed. Which of the following statement is correct?
There are four rivets per pitch length, all in double shear
There are four rivets per pitch length, out of which two are in single shear and two are in double shear
There are five rivets per pitch length, all in double shear
There are five rivets per pitch length, out of which four are in double shear and one is in single shear
The endurance limit of a material with finished surface in comparison to rough surface is
More
Less
Same
More or less depending on quantum of load