Electrical Furnace Melting Method
Electrical furnaces are a type of melting furnace that use electricity to heat metal. They are used in the melting and casting of all types of metal, typically in the production of metal alloys. The electric furnace melting method has evolved over the decades to become the most widely used melting method today. This article will provide an overview of the electric furnace melting method, including its categories, compositions, charging, and power supply.
Categories of Electric Furnace Melting Method
The electric furnace melting method can be categorized into three types: arc furnace, induction furnace, and resistance furnace.
Arc Furnace: The arc furnace utilizes alternating current (AC) or direct current (DC) to generate a dense arc of electricity between two graphite electrodes, which produces a temperature of 3,400 degrees Celsius, enough to melt steel.
Induction Furnace: An induction furnace uses electricity to generate an electromagnetic field above the vessel, which causes the metal to heat up quickly through induction. It has a relatively short melting time and can operate at a higher temperature than an arc furnace.
Resistance Furnace: A resistance furnace uses electricity to generate heat from the resistance of the metal. This type of furnace is used to melt aluminum and other non-ferrous metals. It has a relatively low temperature, but a fast melting time.
Composition of Electric Furnace Melting Method
The electric furnace melting method is composed of many components, including the furnace body, electrodes, refractories and insulating material, and power supply equipment.
Furnace Body: The furnace body is the physical vessel in which the metal is melted and poured. It is typically constructed of carbon steel, stainless steel, or steel with a refractory material.
Electrodes: The electrodes are the points at which the electricity enters the furnace. In arc furnaces, the electrodes are typically graphite rods. In induction furnaces, the electrodes consist of two separate coils of wire.
Refractories and Insulating Materials: Refractories are materials that can withstand high temperatures, and are used to line the inside of the furnace body. They help to prevent heat loss and help to shape the castings during the pouring process. Insulating materials are used to insulate the power supply equipment from the furnace body.
Power Supply Equipment: The power supply equipment includes the power source, such as a generator, and the electrical components, such as cables, switches and resistors, that regulate the current and voltage.
Charging
The charging process is the process of loading the furnace with the desired metals. Charging can be done manually or with a charging machine. In manual charging, charges of metal are added to the furnace manually. In charging machines, small charges are automatically added to the furnace.
Power Supply
The power supply is the source of electricity that is used to power the furnace. It can be AC or DC current. AC electricity is usually cheaper and more efficient, but it has a shorter arc, while DC electricity has a longer arc and is usually more expensive.
Pouring
Once the metal has been melted and charged, it is ready to be poured into the mold. This is done with a ladle and pouring shovel. A pouring pitcher is also used by some for more precise pouring. The liquid metal is poured into the mold, which is then cooled and allowed to harden, creating the desired shape.
The electric furnace melting method is an effective and efficient way to melt and cast metals. It can be used for a variety of applications and is relatively easy to operate. With the right components and good charging and pouring practices, it can be used to produce quality metal products in a timely manner.