It today’s metal industry, heat treatment is an essential component. This is how many metals receive unique properties, and heat treating is used in a wide variety of ways. However, the heat treat furnace is very important and plays a major role. But what is a heat treatment furnace and why is it so important? Let’s take a look at this equipment.
Batch Heat Treat Furnace
A batch furnace is loaded and unloaded manually, unlike continuous furnaces which are fed automatically by conveyors to provide a continuous load of materials in to the furnace. A typical batch furnace has a chamber, shell, heat system and doors to the chamber.
Bogie Hearth Heat Treat Furnace
A typical bogie hearth furnace is a very large batch type furnace. Metal to be heat treated is loaded onto a bogie car. A bogie car is a rail car which is powered by electricity. The bogie car enters the oven, and the oven door is closed and sealed. After the heat treatment process, the door opens, and the bogie car exits. This process is not easy to seal off, and as a result, atmospherically controlled heat treatment cannot be accomplished.
Elevator Furnaces
An elevator heat treat furnace operates on the same principle as the bogie hearth. However, to accommodate very large and heavy loads, the hearth and bogie car are lifted by a motor powered elevator, into position. This eliminates the need for special lifting equipment like cranes.
Bell Furnaces
A bell heat treat furnace can be used for atmospherically controlled heat treating. During this process, a crane is used to lift and place the bell assembly over the hearth and load. This inner bell is employed to seal off the chamber, and the outer bell is lowered to supply heat.
Vacuum Heat Treat Furnace
There are other furnace types like pit, salt bath, and fluidized bed, but one of the most efficient furnaces is the vacuum furnace. Air is removed from the heat chamber during the heat treatment process. Next, special gases are introduced. This makes it possible for carbon or nitrogen atoms to bond with metals without any kind of contamination from the atmosphere. Vacuum furnaces have several important benefits:
* Even and uniform heat
* Computerized controls
* Low chances of contamination
* Quenching can be achieved with quenching chambers. This makes for a very efficient process.
* No oxidation – one of the biggest enemies of steel is oxidation, and when steel is heated normally, it oxidizes rapidly. However, because a vacuum heat treat furnace removes oxygen, oxidation cannot take place.
