Item Description
1.1.1 Seal face
1.1.3 Spring
1.2 Seat
2 Shaft sleeve
6 Cover
8 Pumping screw with flow guide
9 Assembly fixture
14 Shrink disk



  • Cartridge design
  • Single seal
  • Balanced
  • Multiple springs
  • Dependent of direction of rotation
  • Integrated pumping device
  • Stationary spring loaded unit
  • Shrink-fitted seal face


  • Deformation-optimized seal for high sliding velocities and medium pressures
  • Economical due to standardized inner components
  • Universal application for OEM or retrofits of boiler feed water pumps with floating ring seals, labyrinths or packings
  • High flexibility due to adaptation of the connection parts to the pump seal chamber
  • Optimum heat dissipation due to integrated pumping device and optimized seat design
  • Insensitive to shaft deflections due to stationary design
  • Short built

Operating range

Shaft diameter:
d1* = 40 ... 250 mm (1.57" ... 9.84")
Pressure: p1 = 50 bar (725 PSI)
Temperature: t = +300 °C (+572 °F)
Sliding velocity: vg = 60 m/s (197 ft/s)
Axial movement: ±3 mm

* Other sizes on request


Seal face: Silicon carbide (Q), Carbon graphite antimony impregnated (A), Carbon graphite resin impregnated (B)
Seat: Silicon carbide
Secondary seals: EPDM (E), FFKM (K)
Springs: CrNiMo steel (G)
Metal parts: CrNiMo steel (G)

Recommended piping plans

Product variants

Single mechanical seal with integrated jacket cooling, for boiler feed pumps.