Extrusion

A. Is extensively used for making bolts and nuts

B. Is used for reducing the diameter of round bars and tubes by rotating dies which open and close rapidly on the work

C. Is used to improve fatigue resistance of the metal by setting up compressive stresses in its surface

D. Consists of pressing the metal inside a chamber to force it out by high pressure through an orifice which is shaped to provide the desired form of the finished part

Answer: Option D

Solution(By Examveda Team)

Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed through a die of the desired cross-section.
Extrusion is Consists of pressing the metal inside a chamber to force it out by high pressure through an orifice which is shaped to provide the desired form of the finished part.