One-way piston double-seal ball valve

The utility model belongs to the field of valves. The utility model relates to a ball valve, in particular to a one-way piston double-seal ball valve. The ball valve comprises a valve body, a ball core arranged in a middle cavity of the valve body and a valve seat arranged between the valve body and the ball core. The valve seat comprises an outer valve seat body located at the outer end and an inner valve seat body located at the inner end. The inner valve seat is buckled with the outer valve seat; a spring is connected between the front end of the outer valve seat and a spring hole formed inthe inner wall of the valve body, the rear end of the outer valve seat is tightly attached to the ball core, a first sealing ring is arranged between the front end of the inner valve seat and the inner wall of the valve body, the rear end of the inner valve seat is tightly attached to the ball core, and a second sealing ring is arranged in a gap formed among the rear end of the outer valve seat,according to the utility m