Monoflow ball valve and system

A corrosion-resistant monoflow ball valve comprising:

• a corrosion-resistant non-metallic valve body having an internal flow passage, said valve body having a first portion with a first passage section and a second portion with a second passage section, a shoulder at the inner end of said second body portion, and a spacing surface;
• a corrosion-resistant, resilient, compressible ball movable in said passage, said ball being compressed into said second passage section when the pressure on the outlet side of the ball reaches a selected pressure in a sealed position to form a seal to prevent backflow through said passages;
• a corrosion-resistant compression spring in said first passage section for resiliently urging said ball against said shoulder and yieldable in response to a selected pressure on the inlet side of said ball to allow a fluid to flow in one direction through said passage from the inlet to the outlet;
• and
• an inlet member adjustably movable axially relative to said second passage section having an inner end defining said spacing surface which, in use, is suitable for dislodging said ball from a lodged position in said second section upon the movement of said inlet member toward said outlet.

A monoflow ball valve that is resistant to metal-corrosive acids comprising:

• a plastic valve body that is resistant to metal-corrosive acids having an internal flow passage extending along the longitudinal axis thereof, said valve body having a first portion with a first passage section and a second portion with a second passage section, a shoulder at the inner end of said second body portion, and a spacing surface;
• a non-metallic, resilient, compressible ball movable in said passage that is resistant to metal-corrosive acids, said ball being compressed into said second passage section when the pressure on the outlet side of the ball reaches a selected pressure in a sealed position to form a seal to prevent backflow through said passage;
• a metal compression spring with a coating that is resistant to metal-corrosive fluids in said second passage section for resiliently urging said ball against said shoulder and yieldable in response to a selected pressure on the inlet side of said ball to allow a fluid to flow in one direction through said passage from the inlet to the outlet;
• a plastic inlet coupling and spacer member that is resistant to metal-corrosive acids, said member being threaded in said valve body and having an outlet end providing said spacing surface, said outlet end of said spacer means forming with said ball a second fluid-tight seal to prevent flow through said passage;
• and
• a plastic outlet coupling member that is resistant to metal-corrosive acids, said member being threaded in said valve body with an internal passage and an end wall for receiving and holding said spring.

In a pressurized fluid flow system having a compressor and a tank containing a metal-corrosive acid, a monoflow ball valve coupled between said compressor and tank for controlling fluid flow from the compressor to the tank and inhibiting backflow of acid fumes, said valve comprising:

• a corrosion-resistant plastic valve body having an internal flow passage with an inlet and an outlet, said valve body having a first portion with a first passage section and a second portion with a second passage section, a shoulder at the inner end of said second portion, and a spacing surface within said second portion;
• a corrosion-resistant, resilient, compressible ball in said passage, said ball having an external dimension less than the internal dimension of said first passage section to slide therein and greater than the internal dimension of said second passage section, said ball being normally seated on said shoulder in a contacting position to block fluid flow toward said inlet, said ball being movable away from contact with said shoulder to permit fluid flow toward said outlet, said ball being movable into the inside of said second passage section in a compressed position to form a fluid-tight seal to prevent backflow from said outlet to said inlet, the extent to which said ball extends into said second passage section toward said inlet being limited by said spacing surface;
• and
• an inlet member adjustable movable axially relative to said second passage section having an inner end defining said spacing surface which, in use, is suitable for dislodging said ball from a lodged position in said second section upon the movement of said inlet member toward said outlet.