Abstract: A ball or half-ball valve with drain-proof mechanism comprises a body; inner side of the body being formed as a chamber and a through hole communicated to the chamber; an annular seat received in an annular trench of a wall of the through hole; a drain-proof unit; a valve unit installed to the inner side of the annular seat; the valve unit having an axial hole for receiving the stem; and a cover having a size corresponding to that of the through hole of the body; the cover being locked to an outer side of the through hole. The drain-proof unit has three different structures. The elements of the structures are replaceable with each other for being installed to the valve. Each mode is suitable for different environments. In the present invention, the cover can be detached easily for repairing or maintaining the elements therein. It is easy and convenient.

Abstract: A tri-eccentric valve with a symmetric drain-proof ring includes a valve body, a stem, a valve disk, a waterproof washer, and a drain-proof ring. The valve disk is formed as an asymmetric conical shape. The drain-proof ring is an O ring and is arranged in a stepped recess of the valve disk to seal the waterproof washer; the drain-proof ring is symmetric to the axis of the ring. In assembly state, a periphery of the drain-proof ring resists against an inner wall of the annular seat. The drain-proof ring is symmetrical and thus is easy to be installed to the valve disk without to align the drain-proof ring to a specific angle. Furthermore, it can be designed by computers and is manufactured by machines. When dirt accumulates on the drain-proof ring, it can remove the dirt by directly rotating the drain-proof ring.

Abstract: A tri-eccentric valve with a symmetric drain-proof ring includes a valve body, a stem, a valve disk, a waterproof washer, and a drain-proof ring. The valve disk is formed as an asymmetric conical shape. The drain-proof ring is an O ring and is arranged in a stepped recess of the valve disk to seal the waterproof washer; the drain-proof ring is symmetric to the axis of the ring. In assembly state, a periphery of the drain-proof ring resists against an inner wall of the annular seat. The drain-proof ring is symmetrical and thus is easy to be installed to the valve disk without to align the drain-proof ring to a specific angle. Furthermore, it can be designed by computers and is manufactured by machines. When dirt accumulates on the drain-proof ring, it can remove the dirt by directly rotating the drain-proof ring.

Abstract: A ball valve having an actuator of blow out prevention includes a valve body, actuator, and a ball. The valve body has a valve chamber inside thereof and a passageway, top bore, bottom bore extending from the valve chamber. The actuator has a connection portion penetrating through the top bore to the valve chamber, the connection portion has a round groove and a C-shaped buckle. The actuator serves to be rotated by an external driver. The ball inside the valve chamber serves to control the flow of the valve chamber. The ball has a connection hole engaging the connection portion of the actuator. The C-shaped buckle retains the actuator connected to the ball through buckling the round groove of the connection portion receiving inside the connection hole of the ball so that the actuator will not blow out by the pressure of the valve during a damage or maintenance.

Abstract: A ball or half-ball valve with drain-proof mechanism comprises a body; inner side of the body being formed as a chamber and a through hole communicated to the chamber; an annular seat received in an annular trench of a wall of the through hole; a drain-proof unit; a valve unit installed to the inner side of the annular seat; the valve unit having an axial hole for receiving the stem; and a cover having a size corresponding to that of the through hole of the body; the cover being locked to an outer side of the through hole. The drain-proof unit has three different structures. The elements of the structures are replaceable with each other for being installed to the valve. Each mode is suitable for different environments. In the present invention, the cover can be detached easily for repairing or maintaining the elements therein. It is easy and convenient.