Abstract: A containment valve with two butterfly valves at the juncture of a first port and a second port with the two valves pivoting on a common transverse axis. The ports may be coupled and uncoupled between a coupled mode and an uncoupled mode. In the uncoupled mode one butterfly valve body locks the first port shut and the other butterfly valve body locks the second port shut to isolate the contents of the ports, such as chemical dust. Each butterfly valve body has a circumferentially moveable annular locking ring moveable between a first position and a second position. In one position the locking ring locks the butterfly valve body shut when the ports are in an uncoupled mode. In the other position the locking rings hold the two ports in the coupled mode. A spring biased pin lock prevents inadvertent rotation of the annular locking ring. Annular ribs and grooves are provided on the mating faces of the butterfly valve bodies. The ports are hermaphroditic about both the X-axis and the Y-axis.

Abstract: A containment valve with two butterfly valves at the juncture of a first port and a second port with the two valves pivoting on a common transverse axis. The ports may be coupled and uncoupled between a coupled mode and an uncoupled mode. In the uncoupled mode one butterfly valve body locks the first port shut and the other butterfly valve body locks the second port shut to isolate the contents of the ports, such as chemical dust. Each butterfly valve body has a circumferentially moveable annular locking ring moveable between a first position and a second position. In one position the locking ring locks the butterfly valve body shut when the ports are in an uncoupled mode. In the other position the locking rings hold the two ports in the coupled mode. A spring biased pin lock prevents inadvertent rotation of the annular locking ring.