Patent ID: 6499344
Filing Date: 2002-12-31
Classification: E21B,G01N

Abstract:
A well tester for obtaining and assaying a production sample of test fluids from an oil well to learn its production rate, and content of gas if any, oil and water, said tester comprising:a closed vessel having an internal chamber with a lease water supply port, an exit port, and a purge port; a lease water supply line connected to said lease water inlet port and a lease water valve in said lease water line selectively to open or to close said lease water line to flow of fluid; a test fluid line entering said chamber with a discharge end at a mid-elevation therein, a test fluid inlet valve in said test fluid line selectively to open or to close said test fluid line to flow of fluid; a sampling line receiving test fluid from a source connected to said test fluid inlet valve; a return line to return fluids; a by-pass line interconnecting said test fluid line upstream from said test fluid inlet valve to said return line; a by-pass valve in said by-pass line selectively to open or to close said by-pass line to flow of fluid; a purge line through said vessel having an inlet end near the bottom of the vessel; a purge valve in said purge line selectively to open or to close said purge line to flow of fluid; a pressure sensor in said chamber to measure pressure therein; an exit line connected to said exit port; a liquid-sensing probe adapted to sense a gas/oil and an oil/water interface, disposed in said exit line; a gas discharge line branching from said exit line; a gas control valve in said gas discharge line selectively to open or to close said gas discharge line to flow of fluid; a gas flow meter in said gas discharge line; a sample exit line branching from said exit line; a selector valve in said sample exit line selectively to open or to close to fluid flow; said return line being joined to said sample exit line between said purge valve and said selector valve; a flow meter to measure rate or volume of fluid flow in said return line; said return line connecting to said gas discharge line downstream from said gas control valve; whereby with selected settings of said valves, the tester and the supply lines leading to it may be substantially purged of prior samples, the rate of well production determined, the volume of sample obtained in a given time known, and the absolute and relative amounts of oil and water, and gas if present, may be learned.