It is important for us to realize that the safety of operators using an industrial furnace in a manufacturing or processing unit is under threat if certain procedures and standards are not followed properly. To ensure their safety, operators must be given proper safety training and the industrial furnace manufacturers in India and exporters must ensure that their products are compliant with international safety codes.
Buying an Industrial Furnace from Manufacturers
When an industrial furnace is being selected for use, the following factors must be carefully considered:
- The airflow inside the furnace and how it interacts with the product for a particular type of loading pattern.
- Whether or not there is thermal input in sufficient amounts at any given temperature.
All data for quality control can be recorded as soon as the furnace is installed.
Safety Requirements for Class A and Class B Furnaces
According to the NFPA standards, a class B oven is defined as those units which are used only in clean processes, where there are no flammable or volatile substances being heated. Class A furnaces are used for heat treatment on volatile and flammable products.
For electrically heated class B furnaces, the following requirements must be taken care of by the industrial furnace manufacturer:
- Safety switch for air circulation: In case the fan inside the furnace stops functioning, the circuit must be immediately shut down. For this, a safety switch must be integrated into the circuit that will shut the whole system down if the fan does not work.
- Manual reset temperature control: This is commonly known as the high-limit control and should be set ten degrees above the maximum temperature for the furnace. In an event that the furnace produces too much heat, this switch will trip and shut the whole system down.
- Backup contractors: If the primary contractors fail to work properly, then the backup contractors will start and shut down the unit if the temperature rises above the maximum limit.
For electrically heated class a furnaces, the following safety requirements are necessary:
Powered exhaust fans
There should be a powerful fan that operates to push out harmful gases from the building that may form in the area surrounding the furnace. The size of the fan will depend on the number of substances processed and the quantity of fumes that may be produced.
Extra airflow safety switches
This will act as a backup in case the exhausts fail and the primary switch does not function. The second switch will be able to shut the system down in such a case.
A timed purge of all the flammable gases will be necessary to prevent all the fumes from accumulating in the furnace and around it so as to prevent any mishaps.
This is optional since not all class a furnaces will need this. If the furnace needs more power to remove the fumes then there might be a need for the extra power that has to be considered at the design stage by solution furnace manufacturers.
Extra backup contractors
This is also optional and will be required only if the furnace also needs extra kilowatts. This is to ensure that the heaters will shut off if the primary contractors fail to do that.
Internal pressure release
If there is a buildup of pressure in the furnace, this safety feature is necessary so that there can be a controlled release of the pressure.
Therefore, as far as the safety of industrial furnaces is considered, there is no doubt that the proper selection of an industrial furnace is as important as following all the safety designs and procedures.