EXPANSION SEAT VALVE OF APPLYING SCRAPER

摘要

The present invention relates to an expansion seat valve to which a scraper is applied. According to the present invention, powder can be removed by the scraper from a surface of a ball, despite repeated opening and closing operations, thus the powder can be prevented from being left in a gap between the ball and an expansion seat. Also, an airtight performance of the valve can be stably maintained and leak can be prevented since the powder attachment between the ball and the expansion seat is blocked. In addition, reliability of high-pressure processes in which an excellent airtight performance is required can be improved. The expansion seat valve to which a scraper is applied according to the present invention includes a valve main body where a flow path is formed for powder transport; a ball that is rotatably coupled with the valve main body and opens/closes the flow path; an expansion seat that is mounted on the valve main body to be capable of expanding and contracting and expands from the valve main body to be in close contact with a surface of the ball to maintain airtightness; a gas injection unit that supplies gas to the expansion seat so as to expand the expansion seat; and the scraper that is disposed in the valve main body so as to be in contact on a path where the surface of the ball is rotated and moved by the rotation of the ball and separates the powder from the surface of the ball.