By which forging method are bolts produced?

Explanation:

• Forging is a process in which material is shaped by the application of localized compressive forces exerted manually or with power hammers, presses, or special forging machines.
• The process may be carried out on materials in either hot or cold state.
• Typical forged parts include rivets, bolts, crane hooks, connecting rods, gears, turbine shafts, hand tools, railroads, and a variety of structural components used to manufacture machinery.
• The forged parts have good strength and toughness; they can be used reliably for highly stressed and critical applications.
• Upset forging involves increasing the cross-section of material at the expense of its corresponding length. Examples of upset forged parts are fasteners, bolts, valves, nails, and couplings..

Important Points

Press forging: 

• Press forging, which is mostly used for forging of large sections of metal, uses a hydraulic press to obtain slow and squeezing action instead of a series of blows as in drop forging.
• The continuous action of the hydraulic press helps to obtain uniform deformation throughout the entire depth of the workpiece. Therefore, the impressions obtained in press forging are cleaner.