The largest diameter of an external or internal screw thread is known as
Minor diameter
Major diameter
Pitch diameter
None of these
Correct Answer :
B. Major diameter
Related Questions
A locking device extensively used in marine type connecting rod ends is a
Jam nut
Castle nut
Sawn nut
Ring nut
A compound cylinder with inner radius 50 mm and outer radius 70 mm is made by shrinking one cylinder on to the other cylinder, the junction radius is 60 mm and the junction pressure is 1.1 N/mm². The maximum hoop stress developed in the inner cylinder is
3.6 N/mm² compression
3.6 N/mm² tension
7.2 N/mm² compression
7.2 N/mm² tension
When an open coiled helical compression spring is subjected to an axial load (W), the compression produced in the spring will be (where n = No. of active turns of the spring, and G = Modulus of rigidity for the spring material)
2WD3n/Gd⁴
4WD3n/Gd⁴
8WD3n/Gd⁴
16WD3n/Gd⁴
A bench vice has following type of threads
Metric
Square
Buttress
Acme
When bevel gears connect two shafts whose axes intersect at an angle greater than a right angle and one of the bevel gears has a pitch angle of 90°, then they are known as
Angular bevel gears
Mitre gears
Internal bevel gears
Crown bevel gears
The stress induced in the belt is,
Tensile stress
Compressive stress
Direct shear stress
Torsional shear stress
Cap 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 parts
Provided with detachable caps
The size of a gear is usually specified by
Pressure angle
Pitch circle diameter
Circular pitch
Diametral pitch
For a square key made of mild steel, the shear and crushing strength are related as
Shear strength is equal to crushing strength
Shear strength is greater than crushing strength
Shear strength is less than crushing strength
None of the above
Rankine's theory of failure is applicable for following type of materials
Brittle
Ductile
Elastic
Plastic
The function of cutting oil when threading a pipe is to
Provide cooling action
Lubricate the dies
Help removes chips
All of the above
When a bolt is subjected to shock loading, the resilience of the bolt should be considered in order to prevent breakage at the
Thread
Middle
Shank
Head
Form coefficient of spring is
Ratio of coil diameter to wire diameter
Load required to produce unit deflection
Its capability of storing energy
Concerned with strength of wire of spring
The crest diameter of a screw thread is same as
Major diameter
Minor diameter
Pitch diameter
Core diameter
In order to have a connecting rod equally strong in buckling about X-axis and Y-axis, the moment of inertia about X-axis should be __________ the moment of inertia about Y-axis.
Equal to
Twice
Three times
Four times
A sliding bearing which operates without any lubricant present, is called
Zero film bearing
Boundary lubricated bearing
Hydrodynamic lubricated bearing
Hydrostatic lubricated bearing
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 velocity factor for precision metallic gears cut with high accuracy and operating at velocities upto 20 m/s is equal to
0.75/ (0.75 + √v)
3/ (3 + v)
4.5/ (4.5 + v)
6/ (6 + v)
Which of the following pipe joints would be suitable for pipes carrying steam?
Flanged
Threaded
Bell and spigot
Expansion
The material used for brake lining should have __________ coefficient of friction.
Low
High
Moderate
None of these
A backing ring is used inside the pipe joint when making a
Butt weld
Fillet weld
Sleeve weld
Socket weld
The design of the pressure vessel is based on
Longitudinal stress
Hoop stress
Longitudinal and hoop stress
None of these
Which process will increase the fatigue duration of parts?
Finishing and polishing
Shotpeening
De-carburisation
Electroplating
A machine part subjected to __________ is called a strut.
An axial compressive force
A tangential force
An axial tensile force
Any one of these
In designing a connecting rod, it is considered like __________ for buckling about Y-axis.
Both ends hinged
Both ends fixed
One end fixed and the other end hinged
One end fixed and the other end free
The efficiency of a square threaded screw is maximum if the helix angle is equal to (Where φ = Angle of friction)
90° - φ
45° - φ
45° - φ/2
45° + φ/2
The smallest diameter of an external or internal screw thread is known as
Minor diameter
Major diameter
Pitch diameter
None of these
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
If a load W is applied instantaneously on a bar; Then the stress induced in bar will
Be independent of ratio of mass of load W to mass of bar (y)
Increase with increase in y
Decrease with decrease in y
Depend on other considerations
The material commonly used for crane hooks is
Cast iron
Wrought iron
Mild steel
Aluminium