The best practice during new installations is to run copper tracer wire when non-metal pipelines or conduits are being installed. Without tracer wire, finding buried plastic pipes or conduits is expensive and time consuming.
Copper is used as it is an excellent conductor, allowing electromagnetic (EM) locators to easily pinpoint the wire’s position and depth. However, the increasing use of trenchless technologies to install pipes and conduit has created a problem.
Copper is soft and copper tracer wire developed for trenching does not have the tensile strength to handle trenchless installations. Tracer wire breaks become a common occurrence. Often thicker copper wire or multiple wires are used to reduce the break risk, which adds to costs.
A solution has been developed specifically for trenchless applications – Copperhead. Copperhead is a copperclad steel tracer wire, combines the conductivity of copper with the strength of steel. Copperhead wire has a high strength carbon steel core, clad with an outer copper skin. This results in six times the tensile strength of the equivalent gauge of copper.
Copperhead in operation
The Victorian Government, through Regional Development Victoria (RDV), has helped finance the supply of natural gas to eleven regional towns. Over 160 km of gas pipeline is being laid during the rollout, and with it due to be completed in 2017, up to 80 per cent of the plastic pipeline installation is being done via horizontal directional drilling (HDD) to reduce cost and disruption to communities.
During the initial installation work, contractors were experiencing a 30 per cent break rate using traditional copper tracer wire. Re-drilling the pipe after each tracer wire break was proving to be a time consuming and expensive process.
The solution was installing a 1.6 mm high-strength copperclad steel wire from Copperhead Industries. The tracer wire is twisted onto an islet used to connect the poly pipe to the swivel and fed back through the bore hole on the second pass with the polyethylene gas pipe.
Using Copperhead has resulted in a zero break rate, saving installation teams considerable time and money. Where joins were necessary, Copperhead single lug twist connectors were used to join tracerwire ends.
Simple but effective, the plastic connectors contained a contact inside encased in silicone gel. The tracer wire ends were stripped of the plastic insulation, pushed into the connectors and twisted, creating a strong mechanical joint.
Up to five 1.6 mm tracer wires can be joined in a single connector this way. The Copperhead high-strength tracer wire system, including water proof connectors, provides a locating solution for HDD gas pipeline installations, insulated to last the life of the pipeline and strong enough to withstand the stress of installation.
Copperhead products are available in Australia through Tapex, who stock a broad range of excavation safety solutions, including Copperhead tracer wire test stations, Snakeskin tracer wire test risers and grounding anodes to increase tracer signal strength.
For more information visit the Tapex website.
This article was featured in the March edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet, or mobile device, click here.
If you have company news you would like covered in Trenchless Australasia contact Assistant Editor Nick Lovering at nlovering@gs-press.com.au