Seal ring

Abstract

Sandwiching of a foreign matter between a seal ring and a housing is suppressed, and abrasion of the housing and the seal ring is suppressed. The size of the diameter of a second seal portion 3 is set to be larger than the size d 2 of the diameter of an inner peripheral face 81 so that the difference in diameter size between the second seal portion 3 and an inner peripheral face 81 of a housing 80 becomes 1.0 mm or less in a state before the ring body is provided in the annular gap.

1 . A seal ring comprising a first seal portion which is attached in an annular groove provided in a shaft member to be assembled in a shaft hole in a housing and which comes into close contact with a sidewall face on a side of a fluid which is not to be sealed of the annular groove, and a second seal portion which comes into close contact with an inner peripheral face of the housing, the seal ring for sealing an annular gap between the shaft member and the housing,
 having a separation portion provided in one place in the circumferential direction of the ring body, the separation portion provided with, at one separation end, a circular projection which projects in the circumferential direction and, at the other separation end, a circular recess which engages with the circular projection,   the circular projection and the circular recess being provided with mating faces which enable relative movement in the circumferential direction, and   capable of absorbing a change in circumferential length of the ring body by the relative movement in the circumferential direction between the circular projection and the circular recess,   wherein the size of the diameter of the second seal portion is set to be larger than the size of the diameter of the inner peripheral face of the housing so that the difference in the size of the diameter between the second seal portion and the inner peripheral face becomes 1.0 mm or less in a state before the ring body is provided in the annular gap.   
     
     
         2 . A seal ring comprising a first seal portion which is attached in an annular groove provided in a shaft member to be assembled in a shaft hole in a housing and which comes into close contact with a sidewall face on a side of a fluid which is not to be sealed of the annular groove, and a second seal portion which comes into close contact with an inner peripheral face of the housing, the seal ring for sealing an annular gap between the shaft member and the housing,
 having a separation portion provided in one place in the circumferential direction of the ring body, the separation portion provided with, at one separation end, a circular projection which projects in the circumferential direction and, at the other separation end, a circular recess which engages with the circular projection,   the circular projection and the circular recess being provided with mating faces which enable relative movement in the circumferential direction, and   capable of absorbing a change in circumferential length of the ring body by the relative movement in the circumferential direction between the circular projection and the circular recess,   wherein the size of the diameter of the second seal portion is set to be larger than the size of the diameter of the inner peripheral face of the housing by 5 to 10% in a state before the ring body is provided in the annular gap, after that, adjusted to be smaller than the size of the diameter of the inner peripheral face by 1.0 mm or less by a shaping process and, after that, the ring body is attached in the annular groove and provided in the annular gap, expanded by execution of a pre-conditioning interim operation or being heated, and comes into close contact with the inner peripheral face.