Pushing the Limits: When Does It Make Sense to Attempt a Longer and Larger HDD Installation

摘要

Horizontal directional drilling (HDD) methods are being used to install longer and larger diameter installations and inrnareas once thought impossible for this method, with the energy sector primarily driving the need for more challengingrninstallations than what have been completed in the past. Technological advancements and innovative approachesrnwithin the HDD community are driving the application of the HDD method to new and unchartered areas. In the past,rnmost of the industry advancements have been completed through a contractor proposed value engineering processrnwith a shared cost savings approach.rnToday there is an industry pressure to pursue longer and/or larger installations and within difficult ground conditionsrnthat present a greater number of challenges/risk factors than in previous installations. When installation limits arernbeing advanced, design and contractual countermeasures need to be fully established and in place to deal with thernpotential risks that may occur when advancing technological capability. The difficulty lies in balancing the risksrnassociated with pushing a technology limit and how big of a step should be considered.rnThis paper examines the current limits of the HDD industry, discusses typical geotechnical and installation specificrnrisks, and presents a framework that focuses on identifying, characterizing, and managing installation risks tornallow for proper evaluation of the complete risk profile for a particular long length, large diameter, andrnchallenging HDD crossing.