Silicon Nitride (Si3n4) Thermocouple Protection Tube

Silicon Nitride Tube

Silicon Nitride (Si3n4) Thermocouple Protection Tube, Silicon Nitride (Si3n4) Tube

Silicon Nitride (Si3N4) Bonded SiC thermocouple protection tube is mainly used in the production of aluminum, copper, and zinc, as the lining material of the molten pool and electrolytic bath (reduction bath).

The sidelining of the reduction bath is eroding by aluminum and cryolite (used as an additive), but Si3N4 bonded SiC material could not be eroded by aluminum, and do not have a chemical reaction with cryolite. So this kind of material is ideal for the lining bricks of the electrolytic bath. In particular, this kind of bricks has excellent properties of high strength, abrasive resistance and non-conductive, so the copolymer (Al2O3 and Cryolite).

The copolymer likes protective film to protect the working lining and improve the service life of the electrolytic bath. At the same time, the Si3N4 bonded SiC bricks have lower thermal conductivity than silicon bricks, so they can reduce the thickness of the sidewall or input higher power to expanse the loading capacity of the electrolytic bath, and increase the output. Because of the high resistivity of the material, it can reduce the power consumption of the sidewall by about 15%, saving energy and protecting the environment.

Silicon Nitride Tube Features

  • Best producing technology in China. Our tubes can be instead of Japanese tubes in Aluminium melt furnace.
  • Very smooth surface to avoid any blotted metal liquid.
  • Good thermal conductivity.
  • High-temperature strength.
  • Special groove to be easily fixed.

Silicon Nitride Tube Technical Specifications

Density2.8 g/cm3
Phase compositionß-Si3N4, Oxide
compressive strength140MPa
flexure strength35MPa
Thermal conductivity16 w/m*k


Si3n4 Tube Standard size (in stock):

  • OD28 x ID16 x Length 200-1500mm
  • OD45 x ID25 x Length 200-2000mm
  • OD50 x ID25 x Length 200-2000mm

Other Size: Customizable according to your requirement


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