Difference Between SFMR and SITMR Compensation for Hydrostatic Thrust Bearing

Both flat and island type membranes are used in single-action membrane restrictors. But the difference between the single-action flat membrane restrictor (SFMR) and the single-action island type membrane restrictor (SITMR) has rarely been reported in the literature. In this study, we first compared the static and dynamic characteristics of SFMR and SITMR and found that there is a little difference between them when the difference between supply pressure p_s and outlet pressure p_r is not large. Then, we investigated the dynamic characteristics of hydrostatic thrust bearings using both SFMR and SITMR compensation and found SITMR having a better dynamic bearing performance. The reason for this phenomenon is that the mass of the membrane in SITMR is smaller than that of the membrane in SFMR. When the difference between supply pressure p_s and outlet pressure p_r becomes large, SFMR reduces the static flowrate of the lubricant of bearing systems more significantly than SITMR.