The selection of tube type furnace Mosi2 and Sic heating elements
Mosi2 heater rod (distributed left and right of the furnace).
Mosi2 heating element is a resistance heating component made from silicide molybdenum . Sintered molybdenum silicide products in the oxydic atmosphere heated to high temperature, the surface of a layer of dense quartz glass film, it can keep the product is not oxidized. So, Mosi2 heater rod have a unique high temperature oxidation resistance. The maximum operating temperature in the oxidizing atmosphere is 1750 ° C. The resistance of Mosi2 heater rod element does not change with the length of time (the resistance increases according to the temperature rise ), it does not age, so the old and new components can be mixed. The mechanical system of Mosi2 heater rod is same as other ceramic products is easy to break under the normal temperature , but the reasonable usage and installation can be avoided.
Sic heater rod (distributed around the furnace)
Sic heater rod is the use of green high-quality silicon carbide material as the main raw material, the light processing system Pooh, high temperature silicification, in the crystallization of the rod shaped nonmetallic high-temperature heating components. Compared with the metal heating element, the component has the advantages of high use temperature, anti-oxidation, corrosion resistance, long life, small deformation, easy installation and maintenance. Sic heater rod have a greater compared resistance, heated in the air, the heating surface temperature can reach 1450 ℃; from room temperature to 800 ℃ is negative, 800 ℃ above the positive characteristic curve. Sic heater rod have good chemical stability, acid has no effect on it, but alkali and alkaline earth metal oxides in a certain temperature conditions of its erosion. Under the high temperature, water vapor, hydrogen, halogen, sulfur also affect its oxidation and erosion. In order to the furnace temperature and rod to bear the load evenly, must proceed the resistance before installation , to maintain resistance consistent ± 10%; long-term use of electric stove, the individual rods due to other reasons need to be damaged, according to the resistance growth, Resistance to the appropriate bar, can not take any new heater rod replacement. If the bar is damaged more or resistance growth is too large can not reach the required furnace temperature ,replaced into a new stick is better. Test the resistance of replaced rod to the low temperature area.