Theoretical And Experimental Research Of Mechanical-Magnetic Fluid Combined Seal

In the petrochemical industry, the poisonous, harmful, flammable and explosive volatile gas or gas-liquid mixture in the reactor is not allowed to leakage to avoid the production accident. A large number of reactors generally use packing seal or mechanical seal. Both of these two seals can’t meet the zero leakage, therefore, the traditional seals can’t satisfy the requirements of zero leakage and high reliability. To solve such sealing problems of modern industrial equipment like reactor and compressor requiring high pressure and zero leakage application conditions, a novel mechanical-magnetic fluid combined sealing structure is proposed. The theoretical pressure capabilities and sealing performance of combined seal are investigated by the numerical simulation and experimental methods.This thesis focuses on above contents, and completes the following studies:(1)Combined with the actual situation that packing seal and mechanical seal products can’t work normally on such reactor requiring atmospheric pressure and zero leakage conditions. Magnetic fluid sealing equipment that meets the requirement of above conditions is designed for the first time. The magnetic fluid sealing equipment is installed and applied in above reactor successfully for one year, and it always works well, providing reference to combined sealing structure designing.(2)According to each working principle and sealing form of mechanical seal and magnetic fluid seal, the mechanical-magnetic fluid combined sealing structure is designed, and processed into material objects on the basis of establishing combined sealing model.(3)The theoretical pressure capabilities formulas of combined sealing structure are derived, and the theoretical pressure capabilities values are calculated respectively by each structure parameters.(4)According to the related theory of electromagnetic field, magnetic field around the structure is simulated by ANSYS, and the designing rationality is verified.(5)The experimental platform is designed, and the pressure capabilities of static and dynamic sealing liquid are studied. The results show that in a certain rotational speed range, sealing performance of combined seal are significantly better than single seal. Combined seal doesn’t leak for long time under relatively high pressure.