Method for making windows in oil well casings

摘要

A method for making gravel filters in oil well bores. The first step involves ascertaining the location of a producing formation adjacent to a cemented casing in a well bore. Then, a portion of the casing adjacent to the producing formation is cut, enlarging the bore adjacent to the producing formation. Subsequently, a sufficient amount of gravel is deposited in the enlarged portion of the bore to create an effective filter for a producing tube with a screen at its distal end. The distal end is positioned adjacent to the cemented bottom of the well bore. The method maximizes the diameter of the gravel deposited by delivering it exteriorly of the screen of the producing tube and through the annular space defined and sealed between the screen and the casing.