ACA clarifies corrosion complexities

Corrosion is the naturally occurring deterioration of a material or its properties due to a reaction with the environment. It can cause dangerous and expensive damage to many types of structures including pipelines, bridges, buildings and ships. One of the most recent estimates indicates that corrosion costs the Australian economy between 3 and 5% of GDP each year.

In order to promote a more informed debate about the implications and threats posed by corrosion, each year the Corrosion and Prevention (C&P) Conference is arranged to allow asset owners, facilities managers, corrosion engineers and technicians, suppliers and contractors the opportunity to meet and discuss a wide range of topics relating to corrosion and its prevention or mitigation.

Organised by the Australasian Corrosion Association (ACA), the annual C&P Conference brings together industry experts, academics and representatives of commercial organisations to provide opportunities to explore best practice in corrosion management, environmental protection, public safety and economics.

The ACA is a not-for-profit, membership association which disseminates information on corrosion and its prevention or control by providing training, seminars, conferences, publications and other activities. The national industry association was formed in 1955 and represents companies, organisations and individuals involved in the fight against corrosion and promotes cooperation between academic, industrial, commercial and governmental organisations.

According to Warren Green, director and corrosion engineer at Vinsi Partners and Adjunct Associate Professor Deakin University's Institute for Frontier Materials, participation in C&P was a valuable exercise. “I always find them of considerable benefit because the various technical streams are relevant to different groups within industry,” Green said. “The discussion forums allow public interaction and debate on topical issues.”

Green delivered the 2014 P F Thomson Memorial Lecture, which is the keynote address of C&P each year. Green’s topic was about electrochemistry and its effect on the durability of concrete. Vinsi Partners is an engineering consultancy based in Sydney and Green has worked on the assessment, remedial strategy development and maintenance management of many reinforced concrete and steel structures around the country.

In addition to the technical program, the concurrent trade exhibition allows attendees to see the latest equipment and products available to the industry and social events provide networking opportunities for sponsors, exhibitors and attendees.

Traditionally, the conference is held in November; however, the 2014 host city was Darwin so to avoid any problems the wet season might cause, the event was scheduled for September. The focus of the conference also included more technical streams and forums relevant to the oil and gas industry. “I have attended the corrosion conference for many years, so it was encouraging to note that there were a lot of people that I had not seen at previous conferences,” said Green.

The 2014 C&P was themed ‘Get On Top of Corrosion’ to tie in with the location in the Northern Territory and was sponsored by Dulux Protective Coatings. The 2015 conference will be hosted in Adelaide, the internationally regarded food and wine capital of South Australia.

The remit of the ACA also includes educational activities such as seminars and training courses to inform and guide organisations and practitioners about topics including the latest protective technologies and processes. As part of this program, the next ACA hosted event will be on ‘Protective Coatings Preventing Corrosion’ to be held at the Novotel Brisbane, Queensland, on 20 November 2014.

At the Brisbane event, Justin Rigby, coatings consultant at Remedy Asset Protection, will be detailing the need to be flexible and adaptable when developing protective coating projects. “Despite all the best planning in the world,” Rigby stated, “an 'off-the-shelf' solution rarely works out in the field.”

The impact of corrosion is spread through all areas of society and how to manage corrosion is a challenge for owners of suburban industrial units or the owners of structures such as the Sydney Opera House or a gas production platform on the North West Shelf. Selecting and applying the appropriate protective coating is a vital decision for companies and asset owners.

According to Rigby, there are two main ways to protect an asset from corrosion. One is to alter the physical properties of a material by using a technology such as cathodic protection to impress a current into a structure via a sacrificial (galvanic) anode or an impressed current anode to minimise corrosion. The second is to physically isolate structures from the environment by applying a protective coating.

There are many standards relating to the application of protective surface coatings but sometimes compromises may need to be made. When planning for protective coatings it is important to take account of factors such as the geography, access to the structure and climate, all of which impact the cost of the project.

If a structure to be protected is in a remote location, it will be necessary to select the most cost-effective means of transporting materials and personnel to the site. Additionally, remote sites may be exposed to climatic extremes which impact on applying a coating. For example, monsoonal rains in tropical regions would make it difficult to spray a structure.

“When you get to site, there may be odd physical arrangements of pylons and bracing making it difficult for a technician to access all parts of a structure to apply a coating,” said Rigby. This requires careful consideration of the health and safety aspects of effectively protecting the structure, both in regards to the technician working while tethered metres above the ground and properly applying the coating.