US Patent 10054230 Mechanical seal

Provided is a mechanical seal includes a fluid introduction groove provided in a sealing face of a stationary sealing ring and having an opening portion which is opened to the sealed fluid and an end portion which is provided opposite to the opening portion. The end portion being located between respective sealing faces S, the fluid introduction groove introducing the sealed fluid from the opening portion to a clearance between the respective sealing faces S. The fluid introduction groove is provided to be inclined at an acute angle to the sealing face S of the stationary sealing ring in a direction from the end portion to the opening portion.