摘要 |
<p>METHOD OF INJECTING FLUIDS INTO UNDERGROUND FORMATIONS. A method of injecting fluids into underground formations such as oil wells, and particularly advantageous for treating low-pressure formations having bottomhole pressures below normal tubing hydrostatic pressure, utilizes the steps of lowering into the borehole a tubing string, locating near the formation to be treated a partially pressure-balanced valve adapted to support a column of fluid in the string of tubing, and applying pressure to the column of fluid in the tubing to inject fluid through the valve and into the formation. 1a</p> |