Horizontal Directional Drilling (HDD)
The Sacagawea Pipeline Company has contracted two of the most respected names in the HDD industry - JD Hair as designer and Michels Corp. as project contractors.
JD Hair has designed 250+ HDD projects, and in the last few years has designed over (50) 42” HDD crossings.
Prior to drilling, core samples are taken to evaluate the subsurface conditions. This information determines the technical feasibility of the HDD pipeline installation, and the ability of the bore to maintain an open hole condition.
The HDD process is accomplished in 3 stages. The pilot holes are drilled from either side of the river and meet 100 feet below the river bottom. The pilot hole is then prereamed, typically 12’’ larger then the outside diameter of the pipeline. The final step involves pulling the pipeline from the opposite bank through the prereamed hole.
The HDD industry has demonstrated the capability of drilling HDD pilot holes and installing steel welded pipelines up to 20” in diameter over lengths of 2.3 miles. In addition, the pull load for the Sacagawea falls well below the 1,000,000 lb. pull load accepted as the maximum pull load within the HDD industry.
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