| 摘要 |
<p>The present invention is an improved method of installing a flowline below the surface. The method includes the steps of establishing first and second sight relief holes along a linear path, positioning a directional drilling machine on the surface, boring a first portion of a pilot hole from the surface to the first sight relief hole, determining the elevation of the boring tool and adjusting the boring tool to the desired depth, boring a second portion of the pilot hole to the second relief hole, and determining the elevation of the boring tool and adjusting the tool to the desired depth. In another aspect of the invention, a method for directionally boring a flowline is provided. The method includes the steps of establishing a number of sight relief holes along the desired path of the bore, directionally drilling a pilot hole, reaming the material around the pilot hole to the define a bore wherein the bore is at least partially filled with a slurry of the reamed material, and pulling a pipe into the bore wherein a portion of the slurry is displaced into the sight relief holes so that pressure does not develop around the pipe.</p> |
