Vacuum furnace graphite products are increasingly widely used. They are not only used to manufacture heating elements and heat insulation screens of vacuum furnaces but also used to manufacture structural parts such as bracket, material tray, guide rail, bolt, bearing, fan blade, and so on. The application of graphite crucible induction furnace greatly simplifies the design and manufacture of vacuum furnaces, reduces the consumption of metals such as tungsten, molybdenum, tantalum, and stainless steel, reduces the cost, improves the performance of vacuum furnaces, and expands the scope of use of vacuum furnace.
Graphite has good chemical stability, after special processing of graphite, corrosion resistance, good thermal conductivity, low permeability characteristics, is widely used in the production of the heat exchanger, reaction tank, condensing device, combustion tower, absorber, cooler, heater, filter, pump equipment.
The choice of heater material mainly depends on the operating temperature. For low operating temperatures, such as vacuum tempering, cheaper ni-cr alloys can do the job. Molybdenum and graphite are the most popular materials for heat treatment such as quenching furnaces and brazing furnaces that require high temperatures. For many years, molybdenum was almost exclusively used in vacuum heat treatment and brazing furnaces, and there was a common misconception that materials discharged from graphite would react with certain materials and contaminate the vacuum furnace graphite.
Early graphite heaters were limited to simple shapes, and the connections and electrical properties between graphite components were not very stable. With the improvement of graphite material properties and processing technology, more and more heating graphite rods have been applied to heat treatment and brazing furnaces, and the number has exceeded molybdenum heaters. The main advantages of graphite heaters are their lightweight design, rich shape, durability, and ease of maintenance.