Use and precautions of box type resistance furnace/muffle furnace

Use and precautions of box type resistance furnace/muffle furnace. The common names for muffle furnaces in China are as follows: electric furnaces, resistance furnaces, Maofu furnaces, also known as box type resistance furnaces. High temperature muffle furnace is a universal heating equipment. It can be divided into box furnace, tube furnace, crucible furnace. There are domestic muffle furnaces and imported muffle furnaces (American muffle furnaces, German muffle furnaces, etc.). The muffle furnace is a periodic operation type, used by laboratories, industrial and mining enterprises, and scientific research institutions for element analysis and determination, as well as for heat treatment such as quenching, annealing, and tempering of general small steel parts. High temperature furnaces can also be used for high-temperature heating such as sintering, dissolution, and analysis of metals and ceramics.
Use and precautions of muffle furnace
"The refractory material of the new furnace contains moisture. In addition, in order to generate an oxide layer on the heating element, it is necessary to bake at low temperature for several hours and gradually raise the temperature to 900 ℃ before starting use, and maintain it for more than 5 hours to prevent the furnace from cracking due to rapid changes in temperature after being affected by moisture.".
When heating in a muffle furnace, the furnace jacket will also become hot. Keep the furnace away from combustibles and keep it easy to dissipate heat outside the furnace.
"The working life of a heating element depends on the oxide layer on its surface. Breaking the oxide layer will shorten the life of the heating element, and each shutdown will damage the oxide layer. Therefore, it is important to avoid shutdown after startup.".
"During use, the furnace temperature should not exceed the maximum temperature to avoid burning out the electric heating elements, and it is prohibited to inject various liquids and molten metals into the furnace.".
When conducting the ashing test, it is necessary to fully carbonize the sample on the electric furnace before placing it into the ashing furnace to prevent carbon accumulation from damaging the heating element.
After several cycles of heating, cracks may appear in the insulating material of the furnace, which are caused by thermal expansion and have no impact on the quality of the furnace.
The muffle furnace is an experimental article and should not be used for other purposes. Samples must be held in a clean crucible and should not pollute the furnace.
8. When using the resistance furnace, it is necessary to take frequent care to prevent accidents caused by automatic control failure. When there is no one on duty at night, do not use the resistance furnace.
After using the muffle furnace, cut off the power supply to naturally cool it. The furnace door should not be opened immediately to avoid sudden cold cracking of the furnace. In case of emergency, a small slit can be opened first to accelerate the temperature drop. The furnace door can only be opened when the temperature drops below 200 ℃.
10. When using a muffle furnace, pay attention to safety and avoid scalding.