Abstract: Method and apparatus for lining large diameter, deep, boreholes in the earth, which provides a relatively thick lining of cement. A slip form is provided having a cylindrical outer wall of the diameter corresponding to the desired inner diameter of the liner. This is supported on a long central pipe through which cement can be pumped through side pipes and through openings in the wall of the slip form. A base unit is provided with an internal diameter substantially equal to that of the slip form. A petal basket of flexible material is not provided to seal against the wall of the borehole. The slip form is attached to the base by means of shear pins, and the assembly lowered into the borehole until the base is on bottom. Cement is pumped down through the central pipe and out through the openings in the slip form to form a cement liner between the slip form, the base, and the wall of the borehole. When the cement reaches a first set, the slip form is lifted, breaking the shear pins.

Abstract: A cementing tool for providing multiple stage cementing of an oil well including a cylindrical outer case, a longitudinally sliding sleeve valve located therein, an inflatable packer assembly disposed about the outer case with annular check valve means interposed between the interior of the inflatable packer and passages communicating with the interior of the cementing tool. Annular sleeve valve means is interposed between the check valve means and the exterior of the tool and is releasable upon the application of a predetermined pressure differential across the sleeve valve means in response to the application of pressure to the interior of the tool to open the interior of the tool to the annulus between the tool and the oil well bore above the inflated packer. The inflatable packer assembly includes a relatively thin, tubular solid metallic membrane having physical properties allowing it to contain the inflatable pressure and to expand as the inflation pressure is applied to the interior of the packer.