Lengthening of Magnetic Fluid Sealing-Life with Self-Developed Gas Isolator: An Experimental Study

The influence of the self-developed compressed gas isolator,inserted between the magnetic fluid and sealed water,on the sealing life was theoretically analyzed and experimentally investigated with the lab-built test platform for design optimization of gas isolator.The critical pressure and sealing life of magnetic fluid seal were measured.The results show that the newly-designed gas isolator significantly increases the magnetic fluid sealing life because of the effective isolation of magnetic fluid and water and because of the removal of unstable interface of magnetic fluid and water.The measured and calculated results were in good agreement.To be specific,tested at different shaft rotation speeds and at different pressures for a time longer than 120 h,no leakage had been ever observed.We suggest that the newly-developed gas isolator may be of some technological interest in application of magnetic fluid seal for sealing a variety of aqueous solutions.