The ball of the flanged ball valve is elastic. The ball valve and seat seal ring of flange ball valve are made of metal materials. The sealing ratio is very high. The pressure of the medium itself has not met the requirement of sealing, and external force must be applied. This valve is suitable for high temperature and high pressure medium. The elastic sphere is an elastic groove at the lower end of the inner wall of the sphere, and the elasticity is obtained. When the channel is closed, the wedge head of the stem is used to make the sphere open and the seat press tight to seal.
The flange ball valve loosens the wedge head before turning the ball, then the ball will restore the original shape, so that there will be a small gap between the ball and the valve seat, which can reduce the friction and operation torque of the sealing surface.
The opening process of the flanged ball valve
1 in the closed position, the ball is pressurized by the mechanical pressure of the stem and is tightly pressed on the seat.
2 when turning the handwheel against clockwise, the stem moves in reverse, and its bottom angle plane causes the ball to remove the seat.
The 3 stem continues to lift and interacts with the guide pin in the stem spiral groove to make the ball start to rotate without friction.
4 until the full opening position, the stem is lifted to the limit position, and the ball is rotated to the full open position.
The closing process of the flanged ball valve
When 1 is closed, the handwheel is rotated clockwise, the stem begins to fall and the ball leaves the seat to begin to rotate.
2 continue to rotate the hand wheel, the valve stem is embedded in the guide pin in the spiral groove, so that the stem and the ball rotating at the same time 90 degrees.
When 3 is close, the sphere has been rotated 90 degrees in the case of no contact with the seat.
4 the last few turns of the handwheel, the angular plane of the bottom of the stem is mechanically wedged to the ball, so that it is tightly pressed on the seat to complete the seal.