Annealing Furnace System

An annealing furnace is a piece of machinery used to heat a fabric at very high temperatures, to change its hardness and strength properties. Annealing is commonly associated with the manufacture of steel, to relieve internal stresses that shall lead to failure in service and to make a more uniform, or homogeneous, internal structure. This process shall also be commonly used with different metals, glass, and other fabrics to make them fewer brittle and more workable. For metals, an annealing furnace should be capable of heating the fabric to a critical temperature, known as the re-crystallization temperature. This produces changes within the atomic structure and causes the metal to soften.

While annealing temperatures vary depending on the fabric and application, a typical heat for annealing steel is around 1,292F 700C. An annealing furnace is drafted for very uniform heating, followed by a gradual cooling process. To prevent oxidation regarding the material, the heating chamber is airtight, with a slightly positive pressure. The atmosphere within the chamber typically consists of a combination of nitrogen and hydrogen. The 3 primary variations of annealing furnace are batch and continuous.

In a batch furnace, lone or multiple stacks of coils are usually placed on a fixed base inside the heating chamber. A continuous annealing furnace shall heat a fabric as it moves along a conveyor, or on a rotating hearth. A coil of fabric is unwound, treated as it moves through the furnace, and then rewound. The annealing process can take 15 periods to multiple hours, depending on the kind of material, treatment application, and volume regarding the coils. Natural gas is commonly used as heating fuel in an annealing furnace.

A series of burners are located around the inside surface regarding the heating chamber. A fan is many times used to circulate and convey the heat around the fabric being annealed. Most technological annealing furnaces use a computer system to manage the natural gas supply, to monitor and analyse conditions inside the heating chamber, and to drive motors and other mechanical machinery used to convey the annealing material. The heating chamber is drafted to maintain an above degree of heat accuracy and uniformity as the fabric is heated. An annealing furnace shall be purchased in a large variations of sizes, and with a section of capabilities.

Units are manufactured for lab and small-scale applications, to very huge furnaces like those typically used in steel foundries. Annealing furnaces have grow to more efficient in recent years due to innovations, for example improved chamber designs and seals to reduce escaping heat and emissions; better manage of heat and treatment uniformity; combined natural gas and electric heating for higher efficiency; and improved process manage and monitoring capabilities.