Wheatstone Ashburton Pipeline Western Australia
"You must always be prepared to look at different methods when it comes to trenchless technologies. 17 years and I am still learning better ways to put these pipes in efficiently and effectively."
- Business Development Manager, Paul Tredenick
Pipeline Drillers was engaged by Monadelphous KT Pipelines to undertake trenchless works associated with the FRGP 16” gas line in October 2014. After conducting initial scoping and research, Pipeline Drillers was prepared for a challenging job - including varying ground conditions, numerous stakeholders, and crossings inside the FMG Solomon Hub iron ore mine - all in a very tight timeframe. On commencement of the project, Pipeline Drillers deployed the Vermeer 100x120 HDD unit for the small crossings, and their Gallagher 660 Maxi Rig for the longer crossings.
Initial works progressed well, with eight crossings completed as planned in varying ground conditions ranging from sandy loam with light amounts of cobble, to 40-60 MPA hard rock.
Then came the challenging part: the most critical crossings of the pipeline, located inside the FMG Solomon Hub iron ore mine and crossing a haul road and export rail lines. Both bores were 60m long, requiring 608mm enveloper pipes. The ground conditions were difficult, comprising of powdered dry clay with large amounts of cobble. Two attempts were made to pilot hole at the haul road, however the conditions were too loose and binding, making for a very high risk HDD option. Focusing on a positive outcome for their clients, Pipeline Drillers and Monadelphous KT Pipelines' engineers consulted with all parties to identify the best approach to complete the crossings in these very demanding conditions.
After review of all options, including alternative trenchless solutions, the safest and most competent way to install the crossing was decided: pipe ramming, utilising a Grundoram Goliath pneumatic ramming tool, which would need to be purchased from Europe. With planning, assistance and technical advice from John Walsh at TT Asia Pacific, Pipeline Drillers purchased the unit and received it on site (Central Western Australia) from Germany in only five days.