Metal Forging

One of the simplest methods for heating and shaping metal, forging was also the first method for metal working used by human beings in ancient history. Metal is heated to the temperature necessary to hammer it into the desired shape, or, in modern times, to roll or die-cast the metal. In industrial uses, metal forging is done with power-driven hammers; dies are often employed, especially to produce complicated designs.

Small parts are often forged cold, that is, a cold, metal slug is placed in a closed cavity and struck with a punch so that the metal is forced up around the punch. Larger parts are forged hot. Industrial machines used in metal forging include the drop hammer, steam hammer, and hydraulic press.

Dies and Die-Casting

Dies are incredibly versatile devices used for drawing wire, and for blanking (cutting), bending, machine forging and embossing metal. Dies are usually used in modern metal forging in order to obtain the desired shape. In die-casting, molten metal is forced by a plunger or compressed air into a die and the pressure sustained until the metal is solid. Because such dies have sharp outlines and excellent accuracy, they are expensive and usually used only in large, high-speed productions. Carburetor bodies and zippers are representative products.

Metal Forging and Induction Heating

Forging, as opposed to casting, is the method of choice for metals such as iron and steel. Forging strengthens them; casting renders them brittle. Coupled with the speed and exact control of induction heat treating, advanced forging machines are able to produce high-quality parts and increase production.