Ball valve with dual sealing structure

A dual sealing ball valve, comprising:

• a valve body;
• conduit line connectors coupled to both sides of the valve body;
• a ball disposed in the valve body, having a fluid through hole pass therethrough, and rotated to open and close a flowpath through the fluid through hole between the conduit line connectors;
• a sheet holder mounted on an inner circumferential surface of at least one of the conduit line connectors;
• a main sheet tightly contacting and sealing a surface of the ball around the fluid through hole when the flowpath is opened and mounted on a front surface of the sheet holder;
• and
• an elastic sheet mounted on the front surface of the sheet holder, wherein the main sheet overlaps the elastic sheet, wherein the sheet holder includes a sheet ring supporting the main sheet and the elastic sheet in a front direction, supporting the elastic sheet towards the main sheet, and pushed in the front direction by a pressurizing retainer and a sheet cap coupled to the sheet ring and contacting the main sheet to pressurize the main sheet in a rear direction and towards the elastic sheet.