Gas Column Apparatus for Precise Measurement of Oil Well Pressure

Abstract

Published in Petroleum Transactions, AIME, Volume 103, 1933, pages 191–191. The apparatus is composed of sections of small diameter, seamless steel tubingwelded into a continuous flexible tube. At the bottom end a ?- in. pipe nipplewith a 10 to 15-lb. weight is attached, together with a registering thermometerand a pair of ball check valves. The entire length of tubing is coiled in asingle layer upon a drum 4 ft. in diameter which can be attached to theplatform of a truck and provided with devices for winding and unwinding thetubing. Connections are made with the upper end of the tubing through astuffing box, thence to a gas manifold to which a pressure gage is connected.Hydrogen gas is carried in standard 2-ft. cylinders and readings are taken byadmitting gas into the tubing from one (or both) of the hydrogen cylindersuntil the pressure has been built up above that to be measured. At this timethe gas supply is cut off. Excess gas escapes through the open end of thetubing and when equilibrium is reached, the pressure is read at the surfacegage. Corrections are made for the weight of the column of gas. The advantagesclaimed for the apparatus include accuracy and the ability to measure thepressures at any number of points without removing the gage. Among thedisadvantages of the apparatus are the somewhat bulky size of the equipment andits relatively high initial cost.