Heavy Duty Single Cartridge Seal

The P838 series is a heavy duty single cartridge seal intended to provide an excellent sealing performance for pumps. As one of the members of RST Mechanical Seals, P838 is designed to operate in a wide range of process fluids. P838 particularly exhibits high performance in the operation of critical process fluids of hydrocarbon, boiler feed water, sour gas, propane and butane, non-flashing hydrocarbon and flashing hydrocarbon. The improvements in design reliability and robustness are made possible by the utilization of sophisticated Finite Element Analysis (FEA) Engineering Software. These features are further verified by the usage of ProEight’s high-end testing equipment, the patented mechanical seal static tester – AccuTEST and mechanical seal dynamic tester – AccuDYN (Patent Pending).

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  • High flow pattern and distributed flush system
  • Uniform-load Multispring compression unit
  • RST Optimized Seal Face Design
  • Emission Restrictive Throttle Bushing
  • Low-temperature including face (ARCAF)®
    (Subject to design requirements & compatibility)
  • Bolted Auxiliary Gland


  • Centrifugal Heavy Duty Pumps
  • Centrifugal API Process Pumps
  • Centrifugal General Purpose Pumps
  • Positive Displacement Pumps


Temperature - 40 C to 310 C / - 40 F to + 590 F
Pressure Vacuum to 170 bar / 2540 psig
Speeds 55 m/s / 11,000 fpm


  • Oil & Gas Production
  • Petroleum Refining
  • Pipeline
  • Pulp & Paper