Patent ID: 7654314
Filing Date: 2010-02-02
Classification: E21B,Y10S

Abstract:
1. A chemical delivery system for a plunger lift for enhancing oil and gas recovery in a well having a well head and which employs a plunger, which includes: a source of flow enhancing chemicals; and a chamber communicably connected to a top of the well head adjacent a sales flow line and substantially disposed on top of a tubing string and operably disposed thereon and including a ball check valve device which controls communication between a first section of said chamber which receives said flow enhancing chemicals therein from said source for delivery into the well and a second section of said chamber which communicates said flow enhancing chemicals received from said first section to a plunger which is movably disposed along said tubing string as a function of pressure within said tubing string in said well, and means for retaining said ball valve in one of an open position and a closed position as a function of the well being shut in, wherein said ball check valve device includes a ball valve cage in the first section, a first opening formed in said ball valve cage adjacent a first end, a second opening formed at a second end of said ball valve cage, a ball retainer extending inwardly from said ball valve cage and disposed between said ends of said ball valve cage, a ball valve movably disposed within said ball valve cage such that said ball valve can be disposed between the first closed position wherein said ball valve is seated on an annular seat to prevent fluid flow to pass therethrough at said first end and the second open position wherein said ball valve is seated against said second opening at said second end wherein fluid flow is permitted to pass through said first opening and through to said second section and which further includes a dip tube having a first end and a second end, wherein said dip tube is generally movably disposed within said second section and wherein said first end of said dip tube contacts said ball valve under force of the well and moves said ball valve to said open position.