Patent ID: 8042615

Claim:
A shut-off valve for use on a pipe or conduit that has a predetermined cross-sectional area and that carries a high-pressure fluid or gas, comprising: a chamber having input and output ports that can be connected in series with said high-pressure fluid or gas pipe or conduit, a baffle or plate mounted in said chamber between said input and output ports, said baffle having a plurality of holes therein for normally allowing fluid or gas to pass through said chamber from said input port to said output port, said baffle having upstream and downstream surfaces, said plurality of holes in said baffle or plate having an aggregate area at least as large as said predetermined cross-sectional area of said pipe or conduit so that said baffle or plate will not significantly restrict fluid or gas flow through said pipe or conduit when said holes are not obturated, a plurality of obturating balls positioned so that they can be released in said chamber upstream of said baffle, said balls having a predetermined density so that a predetermined fluid or gas flow from said input port to said output port will carry said balls up against said upstream surface of said baffle, said balls having a size larger than said holes so that when said balls are carried against said upstream surface of said baffle they will be lodged in respective holes of said baffle so as to obturate said holes of said baffle and prevent fluid or gas flow through said baffle from said input port to said output port.