초록 ▼

A valve and actuator in combination with a transportation tank to operate off of low pneumatic pressures including a valve having a valve body with a tank end, a valve seat near the tank end of the valve body, the valve seat having a valve sealing surface; a stem chamber extending through the valve

A valve and actuator in combination with a transportation tank to operate off of low pneumatic pressures including a valve having a valve body with a tank end, a valve seat near the tank end of the valve body, the valve seat having a valve sealing surface; a stem chamber extending through the valve body, the stem chamber having an actuator port, a seat port, and an outlet port; a valve stem slidably positioned in the stem chamber, the valve stem having a plug end and a plug attached to the plug end, the plug having a plug sealing surface to sealingly contact the valve sealing surface; an actuator having a hollow housing with a valve end, the valve end attached to the valve body; a plurality of piston assemblies, each having a piston slidable in the housing and a partition fixed in the housing, the piston and the partition defining an actuator chamber; piston spacers joining the pistons so that each piston is fixed in position with respect to the others; the pistons being operatively joined to the valve stem; a helical coil for generating a biasing force to bias the plug sealing surface against the valve seat sealing surface thereby closing the valve; and a passage for introducing pressurized fluid into the actuator chambers so that the pressurized fluid exerts a force against the pistons sufficient to overcome the biasing force to open the valve.

대표청구항 ▼

[ We claim:] [12.] A valve and actuator in combination comprising:(A) a valve having(I) a valve body having a tank end attachable to a manway;(ii) a valve seat positioned in said valve body near said tank end, said valve seat having a valve sealing surface;(iii) a stem chamber extending through said

[ We claim:] [12.] A valve and actuator in combination comprising:(A) a valve having(I) a valve body having a tank end attachable to a manway;(ii) a valve seat positioned in said valve body near said tank end, said valve seat having a valve sealing surface;(iii) a stem chamber extending through said valve body, said stem chamber having an actuator port, a seat port, and an outlet port, said seat port, said actuator port and said outlet port fluidly communicating with said stem chamber, said seat port positioned near said tank end, said outlet port positioned between said actuator port and said seat port;(iv) a valve stem slidably positioned in said stem chamber, said valve stem having a plug end; and(v) a plug attached to said plug end of said valve stem, said plug having a plug sealing surface adapted to sealingly contact said valve sealing surface of said valve seat;(B) an actuator having(I) a hollow housing having a valve end, said valve end fixedly connected to said valve body;(ii) a plurality of piston assemblies, each of said piston assemblies having(a) a piston slidable in said housing, each of said pistons having an upper face and a lower face;(b) a partition in said housing sealingly fixed in position relative to said housing, said upper face of said piston and said partition defining an actuator chamber therebetween;(c) a piston chamber adjacent to said lower face of said piston(iii) piston spacers joining said pistons so that each of said pistons is fixed in position with respect to the others, said pistons further being operatively joined to said valve stem so that said valve stem is fixed in position relative to said pistons;(iv) biasing means for generating a biasing force to bias said plug sealing surface against said valve seat sealing surface thereby closing said valve; and(C) a path means for introducing pressurized fluid into said actuator chambers so that said pressurized fluid exerts a force against each of said upper faces of said pistons in opposition to said biasing force.