Effect of the Surface Roughness of Sealing Face in the Mechanical Seal for Rotary Blood Pumps on the Characteristics of the Shaft Seal

摘要

The objective of this work is to study the effects of the surface roughness of the sealing face in the mechanical seal for rotary blood pumps on the characteristics of the shaft seal. This mechanical seal is incorporated with a circulating cooling water system for the lubrication, cooling and washing in the sealing face. In this paper, the several types of mechanical seals which have the different surface roughness of Ra=0.009μm, Ra=0.088μm, Ra=0.170μm and Ra=0.250μm were used, and the leakage rate, the torque and the temperature change were measured. The leakage was measured by ion chromatography. The torque was measured by a torque meter and the temperature change was measured by a thermometer which was set in the seat ring. As the results, the torque and the temperature rise have the minimum value by using the seat ring of Ra=0.088μm, and the sealed fluid leakage rate has the minimum value of less than 0.1 ml/3h by using the seat ring of Ra=0.009μm.