Functionality diagrams for hybrid mechanical seals with silicon nitride rings

Abstract

Ring-on-ring tribological experiments were performed with hybrid mechanical seals with silicon nitride (Si3N4) rings. The K x PV product, where K is the wear coefficient, P the sealing pressure, and V the linear speed, is proposed as a novel parameter to characterize the total working range of a mechanical seal system, with the advantage of directly indicating the thickness reduction for a certain time of service. The KxPV criterion is represented in a map form called ‘‘functionality diagram.’’ The rotary Si3N4 rings show the better behavior (KxPV=0.05 µm/h) against WC–Co mating faces.