An induction furnace for copper melting uses frequencies that range from fifty cycles per second, also known as mains frequency, to ten thousand processes, referred to as a high frequency. If you own an induction furnace, like any other system, it requires regular maintenance checks to prevent severe deterioration and damage. If you suspect an issue with your induction furnace for copper melting, you may need to know more about the process to steer clear of practices that compromise function.
The first thing you need to know is what induction entails. This process starts with a copper-made coil or another metal used to conduct electricity. As electric current flows through the metal coil, it creates a magnetic field inside the coil and the surrounding area. The effectiveness of the electromagnetic field is determined by the design of the coil and the amount of electricity used. These are critical factors to consider when choosing the purpose of using an induction furnace for copper melting.
Induction Copper Melting
Numerous processes start by making usable products via copper melting. However, out of all the different methods, an induction furnace for copper melting is prized for its enhanced efficiency and speed. Altering the geometry of the induction coil, these furnaces can contain charges as small as the capacity of a mug and as large as hundreds of tons of molten metal. In addition, changing frequency and power allows the induction equipment to process materials such as copper and its alloys and silicon, aluminum, steel, iron and its alloys. When it comes to an induction furnace for copper melting, the equipment can be adjusted to suit individual uses without compromising efficiency.
There are many benefits to using an induction furnace for copper melting, such as inductive stirring. The electricity from an electromagnetic field melts the copper in an induction furnace, and once the metal is completely dissolved, the electromagnetic field creates continuous motion in the bath. This process is referred to as inductive stirring, and the tub is then mixed to create a homogenous blend crucial for the alloying process.
Suppose you are not sure of the amount you need to stir. In that case, several factors are required to help make an accurate approximation: furnace size, power directed to the copper coil, electromagnetic frequency and amount of metal. However, in an induction furnace for copper melting, the stirring amount can be adjusted based on the requirements of specific applications.
Why Copper is Melted in an Induction Furnace
While induction furnaces are used to melt different types of metals, it is commonly preferred for copper due to the high melting temperature of 1083 degrees Celsius or 1981 degrees Fahrenheit. If you are considering copper rotor die-casting, there are two commonly used types of induction furnaces: double push-up Furnaces and tilting furnaces. Let us look at each induction furnace for copper melting and its advantages.
Double Push-Up Furnace
These furnaces use the single-shot melting approach, which melts the copper rapidly in a single shot before the process is repeated for the next shot. This induction furnace offers an obvious advantage: the ability to start and stop the melting process rapidly. This enhances flexibility when you produce a limited number of rotors or similar products. A double push-up induction furnace for copper melting is used to increase productivity during single-shot smelting.
This technique requires using two crucibles heated from a single induction power unit. Each crucible sits on a ceramic pedestal raised by a pneumatically-powered cylinder, and an induction coil surrounds both. Power is transferred back and forth between the two, and once the copper coil is melted, the cylinder pushes the crucible out of the coil, allowing the molten copper to be transferred to the die-casting machine. The induction power can be shared in a matter of seconds with the following coil to start the melting process of the copper in the coil.
While the time used in the single-shot melting process is short, it is not advisable to use a cover gas to prevent the liquid copper from picking up oxygen. However, if it is necessary to use a cover gas, we recommend using an inert gas, particularly nitrogen. A reducing gas that can be easily applied to the top of each crucible, like nitrogen containing 5% of hydrogen, is also an excellent alternative.
Tilting Furnaces
A tilting furnace is used for high productivity, which is usually associated with continuous production. This induction furnace for copper melting is preferred when large amounts of metal need to be melted. It is equipped with a larger crucible than the former, allowing for more flexibility in the choice of charge material, including high-quality electrical grade copper scrap, sheared copper cathode, chopped wire rod or shop run-around scrap. The liquid copper is protected from oxygen pick-up by a ceramic or metal cover placed on top of the crucible, and a melt cover consisting of nitrogen-5% hydrogen is applied on the top of the liquid bath.
Once the copper reaches the desired temperature, tilt the furnace using a hydraulic system to pour a controlled amount of molten copper into the ceramic cup. The cup containing the liquid copper is then transferred to the die-casting machine.
The Benefits of Using an Induction Furnace to Recover Pure Copper
Using an induction furnace for copper melting involves removing all the traces of copper from another object. The refinement process is sometimes conducted along the melting process, but it should be noted that recovering pure forms of metal is not the same as refinement. Acquiring pure copper involves techniques such as heat reduction and acid treatment. On the other hand, induction melting is considered the most effective and efficient process for recovering and purifying different types of metal.
One reason you should consider an induction furnace for copper melting is the enhanced efficiency and better results due to the heating capacity. These are some of the reasons many industries have turned to use an induction furnace for copper melting, guaranteeing quality results without the massive carbon footprint that other techniques leave behind.
