| 摘要 |
PROBLEM TO BE SOLVED: To provide a non-contact type gas seal capable of preventing or suppressing thermal strain generated on a rotary ring caused by temperature difference between regions of the rotary ring.SOLUTION: A non-contact type gas seal includes a rotary ring 3 disposed on a rotating shaft 2, a stationary ring 10 disposed while axially opposed to the rotary ring, closing force generation means for pressing one of the rotary ring and the stationary ring to the other side in a direction to narrow between opposed seal surfaces 3a, 10a of the rotary ring and the stationary ring, and opening force generation means for expanding between the seal surfaces by supplying a gas to between the seal surfaces, and partitions a first space at an axial one side and a second space at the axial other side through between the seal surfaces. The rotary ring is made of SiC sintered body or hard metal. A diamond film d1 is formed on the seal surface opposed to the stationary ring, of the rotary ring, and diamond films d2, d3 continued to the diamond film of the seal surface, are formed on an outer peripheral surface 3b or an inner peripheral surface of the rotary ring, and a back surface 3c as a surface at a side opposite to the seal surface, of the rotary ring.SELECTED DRAWING: Figure 1 |
