Surge prevention device

A surge prevention dual-path valve for pressurized oxygen comprising:

• a housing having an inlet connected to a source of high pressure oxygen, an outlet, and a flow path from said inlet to said outlet;
• a first valve located within said housing, said first valve comprising an upper seat in communication with an upper portion of a pressurization orifice;
• a second valve located within said housing, said second valve comprising a lower seat in communication with a lower portion of said pressurization orifice;
• a lower valve element located within said housing, said valve element having an annular recess for receiving said lower seat of said second valve;
• and
• a threaded piston unit arranged to initially move said upper seat in a first direction to open said pressurization orifice, and to subsequently move said lower seat in an axial direction to open said flow path, said axial direction being the same as said first direction.

A method of operating a surge prevention dual-path valve, said method comprising the steps of:

• moving at least a portion of a threaded piston unit in an axial direction to cause oxygen to flow through a pressurization orifice of a first valve at a first flow rate;
• subsequently moving said piston unit in said axial direction to cause a torque engagement that allows oxygen to flow through a second valve at a second flow rate, said second flow rate being greater than said first flow rate, wherein said step of moving said piston unit to cause said torque engagement further comprises engaging a spring to bias said piston unit, said spring being provided at a lower end surface of said threaded piston unit;
• and
• causing oxygen to flow through said dual-path valve at said second flow rate, through a pressure regulator and then to an operative device.

A method of operating a surge prevention dual-path valve, said method comprising the steps of:

• moving at least a portion of a threaded piston unit in an axial direction to cause nitrous oxide to flow through a pressurization orifice of a first valve at a first flow rate;
• subsequently moving said piston unit in said axial direction to cause a torque engagement that allows nitrous oxide to flow through a second valve at a second flow rate, said second flow rate being greater than said first flow rate, wherein said step of moving said piston unit to cause said torque engagement further comprises engaging a spring to bias said piston unit, said spring being provided at a lower end surface of said threaded piston unit;
• and
• causing nitrous oxide to flow through said dual-path valve at said second flow rate, through a pressure regulator and then to an operative device.