BOGIE HEARTH FURNACE
When parts or charges that are to be loaded onto a furnace are heavy and require material handling facility for loading and unloading, a moving bogie or hearth is provided to make this easier. Once the hearth moves out of the furnace heating chamber parts can be loaded by means of an electrical overhead crane (EOT), gantry system or mobile crane / forklift mechanism. If required, special charge loading mechanisms can also be provided based on the user’s job profile, lack of material handling facility or overhead space constraint. The bogie movement is motorized for easy handling. Similarly the door movement would be with motorized gear drives or hydraulically / pneumatically actuated.
Our standard bogie hearth furnaces can go up to 1500°C, however any special requirements beyond this can also be taken up with a custom design. High temperature applications include sintering, hardening, annealing and normalizing whereas lower temperature applications include tempering and stress relieving. The control system is provided with options to set and control the ramping rate, soaking rate and cooling rate depending on the process cycle, the option of PLC based control is also available. The furnace can be used in open atmosphere or controlled atmosphere as per application. We provide designs with in and out bogie (hearth) movement as well as through and through double door bogie movement if required for an assembly line or process line.
The mode of heating can be via electrical heaters, gas fired or oil fired burners as per the user’s requirement.The furnaces of Thermal Technologies are energy efficient achieved by efficient sealing to prevent undue heat losses and thyristor power controls to limit current consumption. Design factors also ensure excellent temperature uniformity throughout the heating chamber so that parts are universally and evenly subjected to process parameters and heating cycles. Controlled cooling furnace option is also available.
Temperature Range :
Standard Applications :
Annealing, Stress Relieving, Hardening, Tempering, Normalising
Vacuum Formed Ceramic Fibre Boards / Ceramic Fibre Blanket & Module / Brick Lining
Heating Media Options :
Electric / Gas Fired / Oil Fired
Heating Elements :
Nichrome Wire / Special Alloy Resistance Heating Wire / Silicon Carbide Rod Type
Furnace Classification :
Class 2 / Class 3
Thyristor, Programmable Temperature Controller, Temperature Recorder, PLC, SCADA, HMI
Components such as welded structures, cold drawn or formed items require stress relieving as stresses are induced in these processes which will deform the components after they are put in use. Our bogie hearth furnaces for stress relieving or stress relief annealing are available with standard configuration as well as configurations custom for the user’s job profile and volume. For lower stress relieving temperatures, 750°C and below a centrifugal fan based circulation system with stainless steel louvers is implemented to assure adequate convective heat transfer. For higher temperatures the design is based on radiation heat transfer without air circulation.
For full annealing, process annealing or spheroidization depending on the volume of the job or components to be loaded a bogie hearth or chamber type furnace can be selected. Furnaces for these operations are usually provided up to a temperature range of 700°C to 1000°C. Where required (mostly for full annealing) we also provide a controlled furnace cooling option, traditionally with two blowers and an exhaust in an optimum configuration to streamline venting out of heat. Manually adjustable vents or automated VFD i.e. variable frequency drive controlled systems can also be provided for controlled cooling of components.