The diameter of the cylindrical rod on which threads are cut is known as
The crest diameter of a screw thread is same as
A screw thread is defined by its
Which of the following is a wrong statement?
Multi-start threads are used where
(i) large load is required without reducing the cross-section of nut.
(ii) easy screwing is desired as in fountain pens and tooth paste caps. It is used where the use is to impart quick motion in opening and closing without exerting much force.
In square threads, the depth c/and pitch pof threads are related by .
What is the maximum stress induced in the shank of a horizontal bolt when the head is subjected to an impact load of a concentric weight W with a velocity V. Neglect bending due to Wand stress concentration.
The kinetic energy of the moving weight must be absorbed by the bolt upon impact
An M12 steel bolt, 250 mm long, is subjected to an impact load. The kinetic energy to be absorbed is 4 J. What is the stress in the shank of the bolt if there is no threaded portion between the nut and the bolt head? [Take root area = 76.2 mm2]
A = 0.785 x 122 x 10-6
= 0.113 x 10-3 m2
A bolt is used to fasten two members together as shown in figure below. The members and the bolt are of same material and have the same cross-sectional area. What external load W2 will cause separation of the members to occur if the initial tightening load is 30 kN?
W1 = Initial load
W2 = External load Resultant load,
m = deflection in m/N of load for the bolted members
b = deflection in m/N of load for the bolt
Separation of bolted joint will occur if W2 =W
As the material is same, m = b
For applications involving transmission in one direction only, the type of threads best suited is
Buttress threads combines the low frictional resistance of the square thread and the strength of vee-thread when the force acts in one directon only.
Resistance of a bolt can be increased by increasing the
By increasing the length, resistance increases.