History of forging dates back to 4500 B.C. Metals such as wrought iron and bronze were forged by man to produce weapons of wars and hand tools. Forging of iron and crucible steel continued until the end of the 19th century.
It progressed until the Dark Ages. It was the time when most scientific, cultural and industrial advancements stopped. Before Dark Ages, possession of metal was considered as a sign of good wealth. People in Rome even had gods dedicated to the forge.
During the Dark Ages, weapon production was progressing fast. European industries and culture was set back because of constant wars. At the same time, iron industry remained intact due to large demands and need of weapons.
Forgings During 19th Century
In the 19th century, people involved in forging work were skilled at open die and hand forging of wrought iron. At that time, the smiths became very skillful particularly in hammer welding. Large shaft forgings that weighted 10 tonnes or more were built up by the process of hammer welding and forging. In 1856, the invention of the Bessemer steel making process was a major breakthrough for the forging industry. At this time, forgers had a plenty of lost cost steel supply for the production of large quantities of forgings. In the USA, the very first cavity steel forging using a closed-die process started in 1862. In the 19th century, steam engine was invented and showed us ways of modern forging.
Today, forging is used in worldwide industry and has significantly contributed to development of modern machinery and equipment.
Forging has a lot of benefits on the metal being shaped. The metal's strength and toughness are improved due to this process and the repeated hot working results in metal becoming denser and the flow lines to follow the shape of the final component. There are basically three different types forging methods to make a forged part:
Impression Die Forging
Metal is pressed between 2 dies (called tooling), which contain a profile of the desired component. Parts weighing a few ounces up to 60,000 pounds can be made using impression die forging. Some of the parts are forged cold.
In Cold forging, most of the work is done at temperatures up to 2300 degree Fahrenheit. However, a slight variation of this work is done cold. In cold forging, many processes are involved such as cold drawing, bending, cold heading, extrusions, coining to yield a different range of part shapes. Parts being cold forged are processed under different temperature range – from room temperature to a hundreds degree.
Open Die Forging
Work is done between flat dies with no profile is the dies. The key to this method is movement of the part being forged. Parts larger than 200,000 pounds and eighty feet in length can be pressed or hammered into a shape this way.
Seamless Rolled Ring Forging
This type of forging is usually performed by punching a small hole in a round, think piece of metal (forming a donut shape) and then rolling, squeezing or pounding (in some cases) the donut into a thin ring. The diameter of the ring can be from a few inches to thirty feet.
What is forging? Forging is shaping of steel or other metals using compressible forces under high pressure. Metals manipulated by forging possess more strength than parts done by other methods. Forged metals are typically used in weapons, drilling equipment, vehicles and other machinery that depend on highly reliable and stable mechanical operation. Forged steel is used to make stainless steel, alloy, etc. Here are the different steel forging methods that are used today.
Impression-Die forging creates metal parts through extreme pressure. In the impression-die forging, two dies are used, each apply up to fifty thousand tons of pressure on the heated metal. This forging is used to create basic to complex shapes and designs.
Cold forging is a very good alternative to impression-die forging. This techniques requires no or very minimal heating of the metal. It is idle for forming small parts of less than 10 lbs weight. Cold forging is used to form hollow shafts, coins and cup-shaped components.
Seamless Rolled-Ring Forging
Seamless Rolled-Ring Forging is used to produce rings as small as a few centimeters all the way to thirty feet in diameters. The rings can weigh less 1lb and maximum of 350,000 lbs. In this forging technique, a hole is punched in the middle of a rounded piece of metal to create a doughnut shape. The process includes a combination of rolling, pounding and contouring to form rings into machine parts. Seamless Rolled-Ring Forging produces highest-performance, strongest ring-shaped parts for valves, engine bearings, pressure vessels and gears.
Open die forging is used to create large-sized metal shapes. Many open and flat-faced dies continuously work on the metal until it takes the final, desired form. The open-die forging technique is used to produce shafts, rings, hollow cylinders, geometrical shapes out of any metal alloy like steel.
In roll forging, the flat or round bar stock is reduced in thickness and increased in length. Roll forging is performed using two cylindrical or semi-cylindrical rolls, each containing 1 or more shaped grooves. Examples of parts produced by roll forging include leaf springs, axles and tapered levers.
- Forging History
- Forging Defects That Occur on a Forged Part
- Different Steel Forging Methods
- Advantages And Disadvantages Of Forging
- Forging FAQ