Graphite Rotors and Vanes – An Essential Part of Vacuum Pump

  • Low coefficient of thermal expansion, low friction coefficient
  • Excellent self-lubrication.
  • High thermal conductivity and thermal stability.
  • Good chemical stability.
Vacuum pump graphite rotors and vanes are displayed.

The working principle of vacuum pump is to compress gas and discharge it by rotating the graphite rotors and vanes. Specifically, as the graphite rotor rotates, the space between the vacuum pump graphite vanes and the pump body continuously changes, thus sucking, compressing, and discharging gas. The main function of the graphite blades is to capture the gas and move it from the low pressure area to the high pressure area when they rotate inside the vacuum pump. The quantity, shape, and material of the graphite vanes have an influence on the performance and service life of the vacuum pump.

Vacuum pump graphite rotors and vanes have good self-lubrication and wear resistance and can work normally in dry-running state without additional lubricating oil or grease. Therefore, they can effectively avoid the contamination and damage to the vacuum pump caused by lubricating oil or grease. Meanwhile, they have good corrosion resistance and high temperature resistance, and can adapt to harsh working environments, so they are widely used in dry vacuum pumps.

  • Low friction, low coefficient of thermal expansion.
  • Excellent self-lubrication.
  • High thermal conductivity and thermal stability.
  • Good chemical corrosion resistance.
  • Wear resistance and high mechanical strength.
Table 1: Specifications of Graphite Rotors and Vanes
Grade Density (g/cc) Porosity Shore Hardness Compressive Strength (Mpa) Flexural Strength (Mpa) CTE (×10-6°C-1) Max Working Temperature Application
M105K(Resin Impregnation Vanes) 1.8 2% 60 110 65 200 °C Carbon vanes
M106K(Resin Impregnation) 1.8 2% 65 180 60 4 200 °C Seal rings, bush
M106D(Antimony Impregnation) 2.3 3% 80 230 80 4 550 °C Seal rings, bush
M254A(Copper Impregnation) 2.4 2.5% 70 170 65 500 °C Seal rings, bush
  • 1 MPa = 10.2 kgf/cm2; 1 W/m.k = 0.86 kcal/cm.h.°C
  • These properties are typical values and not guaranteed.