The Right Foundry Machine Tool For The Job
Commonly found in industrial facilities, you’ll find furnaces and ovens?perform a variety of functions. These functions include melting metals, heating of metal to alter its hardness, and curing of metal parts. These machine tools are commonly used in foundries, but some can be used in other areas such as the main production floor or in a lab.
The key is to find the right heating and?melting machine tools for the job. This furnace and oven guide was created just for that purpose.
Metals such as iron, silver, gold, copper, steel, aluminum and brass can be processed using the following furnaces and ovens:
Furnaces – Induction Heating and Melting
Induction furnaces are electric furnaces in which metal is heated by large amounts of electricity being inducted into it. The process consists of a high frequency alternating current being passed through a strong electromagnet into the electric conducting material. Furnace frequencies range from 50 Hz to 400 kHz or higher depending on the capacity of material being melted and the speed at which it can be melted.
The metal is heated from the inside by the creation of Eddy currents, also known as Foucault currents. This causes the metal to melt once the currents have heated the metal past its melting point. Overheating of the furnace itself it prevented by water cooled tubing which is wrapped around the outside of a layer of refractory, tightly packed around the graphite crucible.
The biggest advantage of using an induction furnace is that they are the cleanest, most energy efficient and easily controlled of all melting furnaces.
Induction ovens work similarly, but have a less powerful electromagnet and lower frequency of electricity. These ovens can be used for altering the hardness of metal parts or raw material.
Typically, an oven would be used to make metal softer in preparation of the next production process such as milling or extruding. A finished metal part can also be cured or hardened to its final hardness in an induction oven.
Smaller induction ovens can be used in labs to heat up liquids or test metal purity. Some are even small enough to be placed on a countertop and function by the electricity being transferred into a metal plate. A beaker, pan, etc. can then be placed on the plate to heat its contents.
Annealing furnaces are also known as heat treat furnaces and use gas or electricity to create internal heat. They are long, enclosed machines with an internal belt used to carry material and parts through the furnace.
Annealing furnaces consist of a series of chambers, which can each be adjusted to heat and/or cool the material in such a way as to change its properties in specific ways. Heat treatments are most commonly used to harden or soften materials in preparation of further production operations.
These furnaces are capable of completing heat treatments in a matter of minutes rather than hours thanks to use of Rapid Thermal Processing (RTP) or Rapid Thermal Annealing (RTA). This makes this particular type of furnace perfect for a facility in which parts or material continuously need to be softened or hardened on a regular basis.
Vacuum Furnaces and Ovens
Vacuum furnaces are used to heat metals to extremely high temperatures in an atmosphere free from outside gases. This type of furnace can be used for heat treatment, sintering and brazing applications.
Some benefits of using a vacuum furnace include: uniform heating from 2000 – 2800 degrees F, minimal chance of contamination from foreign gasses such as carbon, decreased chance of material oxidation and faster cooling of heated materials.