Industrial forging has many names which often get confused with different methods.
One of the oldest terms, “drop forging” describes a hammer where the weight of a falling ram, powered only by gravity, provides the force to strike and shape metal. Machines were invented using a variety of techniques to rapidly raise the ram after each blow, allowing successive hammer strikes. Today, even forgings made in power hammers, where force is applied to drive the ram against an opposing anvil, are sometimes referred to as “drop forgings”. While true drop hammers are still in use, the trend in hammers is to utilize applied power both to raise and lower the ram. With the modern drop forging process, a powered down strike allows faster blows of controlled energy which can be an advantage in productivity depending upon the range of items being forged.
Several designs of machines, described as forging presses, typically perform a forging “strike” at speeds somewhat slower than those achieved by hammers. These include mechanical presses, where the action of the ram moving against the anvil is powered by the rotation of an eccentric shaft or crankshaft, typically powered through a series of links, shafts and wheels driven by an electric motor. Hydraulics power another type of forging press, where pumps and valves control high pressure fluid through pipes connected to a cylinder that drives a ram, connected to the cylinder rod, against an anvil. Screw presses raise and lower the ram by turning a threaded shaft, the mating nut attached to the ram running up and down the length of the threaded shaft as the shaft rotates first in one direction, then the other. Each type of press can have significant design variations depending upon the intended use of the machine.
Machines in the class operate in a similar fashion, the ram moving in a horizontal direction to press against the end of a piece of bar stock, to increase volume and form a shape at the end of the bar. Visit our Upset Forging page to find out more.
More forging processes designed for specific product designs. Ring rolling, High Energy Rate Forging, press forging, and plastic deformation are forging methods often used with explicit properties in mind. Visit our Additional Forging Types page to find out more.