The double mechanical seal with buffered fluid (DD) is suitable for a max. viscosity of 1.000 Pas, because the internal parts of the mechanical seal do not get in contact with the pumped fluid. All the internal parts are lubricated by the buffer fluid. The pressure on the suction side can be within a wide range: from vacuum conditions to max. 15 bar.
Min. suction pressure: Vacuum
Max. suction pressure: 15 bar (psig)
Max. temperature : 300°C (580°F)
Viscosity: 0,2 to 1.000.000 mPas (cP)