Written by Kerryn Caulfield, Executive Director, Composites Australia Inc.
The December 2019/January 2020 fires in Australia left thousands of kilometres of the network damaged with more than 5,000 power poles destroyed or requiring replacement. For Lachlan Nicol, Engineering Manager at Toowoomba’s Wagners Composite Fibre Technologies (WCFT), the event was a lived experience. “You can’t live in the area and not be touched by the fires. In 2019, smoke haze cloaked the Darling Downs for months. Water and power supply were compromised with many residents losing the service of both. While we’d been developing utility poles as an extension of our legacy cross arm range, the unprecedented bushfire season gave us confidence that our technology could improve the resilience of the electrical grid in regional communities.”
High on the hill overlooking Wellcamp Airport is the ever increasing cluster of factories owned and operated by Wagner Corporation, inside each of which is composite production equipment that is actively transforming community infrastructure – from road bridges, marine piers and pedestrian structures to energy transmission assets. Its technology is a unique modified pultrusion process known as pull-winding which utilises resin injection. Wagner’s technology provides superior mechanical properties than those of standard methodology using glass mats and a resin bath.
Foundational products such as the electrical crossarms for utility poles are now used across Australia and around the world with over 1.2 million supplied globally. Backed by a team of experienced engineers, technicians, trade staff and ongoing investment in automation, WCFT is now producing a crossarm – for low and high voltage distribution, transmission and sub-transmission requirements – every 69 seconds across a family of 200 designs. Associated electrical infrastructure products include certified live line lifting beams, hurdle frames, substation infrastructure, arm braces, stay insulators, riser arms, and isolation platforms.
For Wagners, owning and operating a range of sites including its own quarry and Business Park provided unique opportunities to test and monitor its proprietary products and technology. Rows of composite light poles stand as sentinels along the roads that circle the Wellcamp Airport and Business Park that opened on the outskirts of Toowoomba in 2014. Its utility poles, which were initially installed in the company’s quarry, have now been rolled out into rural Australian bushland.
According to Lachlan, economic factors that have conventionally affected market acceptance of composites in the past have shifted with Australian energy networks moving expeditiously toward full composites poles over the next few years. “The additional cost of composites has always been an obstacle for asset owners. But stock of suitable timber has become problematic and unreliable as a result of the 2019-20 fires and ensuing floods. There is also uncertainty surrounding the state-run timber supply contracts and imported timbers.”
The standard Wagners CFT utility pole offerings are typically 12.5 metre long and 300 millimetres in diameter with a 13.5 millimetre wall thickness. Its pull-winding technology ensures an exact unchanging parallel cross-section. The poles are glass fibre centric and specified to carry 6kN with a tip deflection of 5 per cent under service load; and while they are specified for 60 years, the testing completed on the product shows that the life span would far surpass this. Gold Coast injection moulding specialists AMEC Plastics produces the top and bottom pole caps which were design by Wagners to specifically suit their utility pole profile sizes.
Ensuring the long life span, each pole is coated with a specially formulated UV-resistant fluoropolymer coating to resist extreme weathering of direct sunlight and harsh marine environments. The harshness of the UV impact within the Australia environment is something that new players in the composites industry often don’t fully appreciate which is why Wagner’s coats all manufactured products and ensures maximum durability.
Research and development and testing have been done in-house within the company’s Engineering Group. During the development phase, Wagner’s geared up to undertake the necessary fire testing in house which helped with the iterative R&D work. Part of the client requirements was for the poles to achieve a BAL 40 fire rating in accordance with AS1530.8.1. Coefficient of thermal expansion is 5.03 x10-6, which is about 50 per cent of the coefficient of expansion of steel – performance properties that have been engineered by allnex sophisticated resin technologies.
“The inventory of beneficial properties of our utility poles that include low-weight, high strength, UV resistant, non-conductive and non-corrosive provide a compelling whole-of-life procurement case for asset owners, particularly for areas prone to bush fires, termites, or aggressive soils. We hope to see the market for our utility poles increase to significant volumes over the next few years,” advised Lachlan.