This paper describes the deformation of the sliding surfaces of a mechanical seal. That is, the values of the deformation due to the seal pressure and the oil film pressure are analyzed theoretically, in the analysis a mechanical seal is considered as a ring having rectangular section. Then the seal characteristics are tested by some analogical experiments in which a surface having the shape of theoretical deformation are used as a sliding surface of a mechanical seal.
And the followings are obtained.
1) The distribution of the oill film pressure between the sliding surfaces is varied by the deformed shape of the surfaces, then the necessary thrust force to seal the fluid is greatly influenced to the shape also.
2) It is necessary to balance the moments arround the center of the axial section for decreasing the amount of the surface deformation.
3) In the outside type seal a concave shaped surface which gives convex shape oil film pressure distribution shows more stable seal caracteristics than a plane shaped one.