John Crane Type 21
The Type 21 is an all purpose seal which rotates with the shaft against a stationary mating face. The Type 21 features mechanically crimped components eliminating the use of adhesives. We have many sizes and material configurations for engineers to choose from.


Materials configuration:
  • Stationary Ring (Alumina 99%/Alumina 99.5%/SiC/SSiC/TC)
  • Rotary Ring (Carbon/SiC/SSiC/TC)
  • Secondary Seal (NBR/EPDM/Viton)
  • Spring and Punched Parts (SS304/SS316)
Working conditions:
  • Mediums: Water, oil, and chemical mediums with weak corrosion
  • Temperature: -20°C~150°C
  • Pressure: ≤0.8MPa
  • Speed: ≤ 10 m/Sec