1. Description of technologies and principles

Basic principle

The main seal of a mechanical seal is a face seal made between two rings in contact, one rotating and integral with the shaft, the other fixed and integral with the device frame.

The closing force between these two faces is ensured by an elastic element (spring of various types or bellows) to which is added the effect of pressure on one of the rings.

In order to ensure the tightness of the various elements, and in particular of the ring integral with the elastic element, the main seal is completed by secondary sealing elements of two types: static and semi-dynamic (sealing of the face mounted on the elastic closing element). These seals are typically provided by elastomer gaskets, elastomer membranes or metal bellows.