Steel billets are reheated before rolling or forging through a process known as billet heating. This process involves subjecting the billets to high temperatures to make them more malleable and easier to shape. There are several methods commonly used for billet heating, including:
1. Furnaces: The most common method of reheating steel billets is through the use of furnaces. These furnaces are typically gas-fired and can reach temperatures of up to 1,200 degrees Celsius. The billets are loaded into the furnace and heated for a specific period of time to achieve the desired temperature. The furnace provides a controlled environment, allowing for even heating and uniformity.
2. Induction heating: Another method used for reheating steel billets is induction heating. This process utilizes electromagnetic induction to heat the billets. An alternating current is passed through a copper coil, creating a magnetic field. The billets are then placed inside the coil, and the magnetic field induces eddy currents within the billets, generating heat. Induction heating offers precise temperature control and rapid heating rates, making it suitable for high-speed production.
3. Electric resistance heating: Electric resistance heating is another technique employed for reheating steel billets. This method involves passing an electric current through the billets, causing them to heat up due to the resistance encountered. Electric resistance heating can be achieved using various types of heating elements, such as graphite electrodes or resistance heating wires. This method offers precise temperature control and is commonly used for smaller-scale operations.
Regardless of the heating method used, it is essential to carefully control the temperature and heating time to ensure the billets reach the optimal temperature for rolling or forging. The reheating process allows the steel to become more pliable, reducing its hardness and increasing its ductility, making it easier to shape and form into the desired end product.
Steel billets are reheated before rolling or forging by passing them through a furnace or a reheating furnace, which raises their temperature to a specific range. This process, known as billet reheating, is crucial as it improves the billets' malleability, making them easier to shape and work with during the subsequent rolling or forging operations.
