Ring forging is the process of manipulating metal into a hollow circular or cylindrical “ring” shape by applying localized, compressive force.
The process of forging has been around for millennia, and the hammer and anvil, though increasingly diverse, have stood the test of time along with it, as the most commonly used tools to carry out the process of ring forging.
There are a few ways to complete ring forging, all of which are fairly simple. The first method begins with cutting a stock piece of metal to an appropriate length. After this, the metal is upset, which is a process by which the metal’s length is decreased and its cross-section is increased. Then, the metal is pierced through the center in order to create a hole.
After the piercing, the piece is placed on a mandrel or saddle, where its intended form is gradually shaped by the up and down motion of a forging die. The forging die hammers from above as the piece is incrementally rotated.
Another form of ring forging is called roll forging. A ring made through roll forging is completed with a round or flat bar and one or two cylindrical or semi-cylindrical rolls, which each contain one or more grooved shapes. A heated bar is inserted into the rolls, rotating when the bar hits a certain spot, which progressively shapes it as it rolls. After this, the bar is inserted into the next set of grooves or turned around and reinserted to the previous grooves.
This process repeats itself until the desired size and shape are acquired. After the initial ring forging, pieces can undergo secondary processes, in order to change something about them. Secondary processes include heat treating, machining, plating, painting, drilling, welding and generally fabricating.
Ring forging has a few advantages over casting and machining, such as increased structural integrity and greater strength. Due to the fact that, as the metal is shaped during the forging process, its grain deforms to adapt the general shape of the piece, the ring’s grain is continuous, making it stronger than a cast or machined ring.
Ring Forging Informational Video