The edge criteria for magnetic-fluid seals durability research are critical for the seal’stechnological usefulness. The magnetic fluid seal technology in water is much moredifficult technological problem in comparison to gas or vacuum environment. There isalways problem with immediate contact between magnetic fluid and the environmentaluninspected liquids. In the paper are presented ways of experiments definitions carried outwith multi-stage rotating magnetic fluid seal operating in permanent contact with utilitywater. The special test procedures have been elaborated and practically used, with theaim to define main characteristics of magnetic fluid seals. These characteristics were: critical pressure,critical motion velocity and working life of the seal. Some grades of commercial, silicon based magneticfluids of hydrophobic properties were tested in sealing system. The test stand and its features as well asresults of tests are presented in the form of tables, cross section draws and diagrams. In conclusion onecan see that multi-stage magnetic-fluid seals could be efficiently used in water for rotating shaft seals ina limited range of motion velocity and work lasting.
