Abstract: The mechanism of a kind of adaptive contacting mechanical seal which is applied in pressurized water reactor nuclear coolant pumps in different operating conditions is investigated by the hybrid lubrication model coupled with thermal and elastic deformation and elastic hydrodynamic lubrication model. The floating structure of static ring with O-ring is given, and its performance is compared with interferential structure applied in import product. A full-scale vertical experiment rig for adaptive contacting mechanical seal is set up. The seal performance of the adaptive contacting mechanical seal in two statuses is obtained from the experiments which prove the two theoretical models. The feasibility and reliability of floating structure of static ring is verified by the experiments also. These results are beneficial to the domestic design and manufacturing of mechanical seals in nuclear coolant pump.

Key words: adaptive mechanical seal, contacting mechanical seal, nuclear coolant pumps