In order to permit the thermal expansion/contraction of tubing, it should be
Crimped
Honed
Flared
Bent
Correct Answer :
D. Bent
Related Questions
The cold working of metals is carried out __________ the recrystallisation temperature.
Above
Below
At
None of these
A metal pipe of 1 m diameter contains a fluid having a pressure of 1 N/mm². If the permissible tensile stress in the metal is 20 N/mm², then the thickness of the metal required for making the pipe will be
5 mm
10 mm
15 mm
25 mm
The permissible stress for carbon steel under static loading is generally taken as
2000-3000 kg/m²
3000-4000 kg/cm²
4000-4500 kg/cm²
7500-10,000 kg/cm²
According to Indian standards, a bolt thread of 6 mm size of coarse pitch and with allowance on the threads and normal tolerance grade is designated as
M6
M8
M6 - 8d
M8 - 6d
The stiffness of a closely coiled helical spring subjected to an axial load W is equal to (where G = Modulus of rigidity, and n = Number of active coils)
Gd⁴/ 8D3n
Gd3/ 8D3n
Gd⁴/ 4D3n
Gd⁴/ 8D²n
Belt slip may occur due to
Heavy load
Loose belt
Driving pulley too small
All of the above
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
A bolt of uniform strength can be developed by
Keeping the core diameter of threads equal to the diameter of unthreaded portion of the bolt
Keeping the core diameter smaller than the diameter of the unthreaded portion
Keeping the nominal diameter of threads equal to the diameter of unthreaded portion of the bolt
None of the above
Crushing resistance required to crush the rivet per pitch length is
p.d.σc
p.t.σc
n.d.t.σc
(p - d) t.σc
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
If P1 and P2 are the tight and slack side tensions in the belt, then the initial tension Pi (according to Barth) will be equal to
[(√P1 + √P2)/2]²
P1 + P2
2 × (P1 + P2)
[2 × (P1 + P2)] + Pc Where Pc is centrifugal tension
A plate with an elliptical hole in the centre, with semi-major axis (A) perpendicular to the direction of loading and semi-minor axis (b) along the direction of loading, is subjected to a pull P. The maximum stress induced at the edge of the hole is equal to (where σ = Stress for a plate with no hole i.e. nominal stress)
σ [1 + (b/2a)]
σ [1 + (2a/b)]
σ [1 + (b/3a)]
σ [1 + (3a/b)]
The cam follower extensively used in aircraft engines is
Knife edge follower
Flat faced follower
Spherical faced follower
Roller follower
A locking device in which the bottom cylindrical portion is recessed to receive the tip of the locking set screw, is called
Ring nut
Castle nut
Sawn nut
Jam nut
When a material is subjected to fatigue loading, the ratio of the endurance limit to the ultimate tensile strength is
0.20
0.35
0.50
0.65
The dedendum circle diameter is equal to (where φ = Pressure angle)
Pitch circle diameter × cosφ
Addendum circle diameter × cosφ
Clearance circle diameter × cosφ
Pitch circle diameter × sinφ
The pipe joint mostly used for pipes carrying water at low pressures is
Socket joint
Nipple joint
Union joint
Spigot and socket joint
A double strap butt joint (with equal straps) is
Always in single shear
Always in double shear
Either in single shear or double shear
Any one of these
In order to ensure self locking in a screw jack, it is essential that helix angle is __________ friction angle.
Larger than
Smaller than
Equal to
None of these
Castle 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 is middle of nut and then slot reduced by tightening a 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 spitted and bent in reverse direction at other end
For unequal width of butt straps, the thicknesses of butt straps are
0.75 t for narrow strap on the inside and 0.625 t for wide strap on the outside
0.75 t for wide strap on the inside and 0.625 t for narrow strap on the outside
0.75 t for both the straps on the inside and outside
0.625 t for both the straps on the inside and outside
The objective of crowning of the flat pulleys of belt drive is to
Prevent the belt from running off the pulley
Increase the power transmission capacity
Increase the belt velocity
Prevent the belt joint from damaging the belt surface
A leaf spring in automobiles is used
To apply forces
To measure forces
To absorb shocks
To store strain energy
The included angle for the British Association thread is
29°
55°
47.3°
60°
The resilience of a bolt may be increased by
Increasing its shank diameter
Increasing its length
Decreasing its shank diameter
Decreasing its length
When the fulcrum is in between the load and effort, the lever is said to be of
First type
Second type
Third type
Any one of these
The process which improves the machinability of steels, but lowers the hardness and tensile strength is
Normalising
Full annealing
Process annealing
Spheroidising
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
Transverse fillet welded joints are designed for
Tensile strength
Compressive strength
Shear strength
Bending strength
For high speed engines, the cam follower should move with
Uniform velocity
Simple harmonic motion
Uniform acceleration and retardation
Cycloidal motion